Friday, 6 February 2026

IVA fixes

 This is just a placeholder for now, as I've not got any photos or anything to add. But at least I can make a start.

Fault 1. NS exhaust mounts insecure and missing

Nothing to highlight here, I'll take a before and after photo.

Fault 2. rear number plate mount, not radiused.



What I'll need here is a proper surround on the number plate, so similar design but with a bead around the outside at the correct size. Euro space option 2 is 340 x 240 so I'll do everything to that size.

Unfortunately I made a mistake on the plates, that one attached as an example is the 'small space' plate which is 300 x 150. The euro option 2 is bigger by some margin.

Fault 3. Direction indicators, too low.


I'll move these up and out so they still comply with the viewing angles, but actually sit above the allocated holes. I'll order some surface mount bulb holders and design the 3D print around them. 

Fault 4. Design rear axle weight too low

This one has already been fixed! When I got back yesterday I pinged a query to the approvals email address, and they responded saying that they'd made the change. I was dreading this one, turns out it's the easiest one to sort. 

Fault 5. Clutch fork fouls brake pipe when depressed.


This photo shows what's going on. Turns out that I had noticed the proximity earlier in the build, but thought that the lever movement wouldn't a problem. I was wrong. From the photo it looks like I have some flexibility in routing that better, I might even put a protective sleeve on it.

Fault 6. Fuel pipe near gearbox mount fouling on mount

Hmm, the issue is quite clear on this photo, the pipes are too far from the side panel. I'm not entirely sure how I've ended up on that position, but it shows what the fix is. I need to undo that fixing and turn it round. Given it's protected I could have it resting up against the panel and it would be fine. 

I will need to make sure that moving it doesn't pull it too tight somewhere else but that means both pipe fixes are pretty simple. 




IVA day

Turns out the story isn't quite finished yet! I guess I'll start from the beginning...

The morning started at 'way too early o'clock', with a plan to get to Bristol for around 7. In the end I arrived at 7:30, thanks in no small part to the M6 being partly closed and some very unusual local traffic near the test station. 

Still, I got there. It was very cold, very wet and very early. The sun hadn't really come up by the time I was getting it unloaded. 



The tester came up to me as I was getting things sorted, offered a coffee and use of the facilities, and was happy for me to get things warmed up and ready for testing. It was emissions first so everything had to be hot.

And of course, that's where the rollercoaster started, with the biggest challenge! I've not been able to test emissions for obvious reasons, and the testing didn't disappoint. The initial test failed with CO too high, then a retest also failed. But as far as I could tell it was being done as a CAT test on the more modern limits, and this car would never meet them. Once he'd checked all the details and convinced the computer that it needed to be tested as an early CAT test, then it went fine. Of course, the exhaust was absolutely screaming, so I just expected the noise test to fail, more on that later.

The main thing from the emissions test was not the test itself, but more the mindset of the tester. Given he tested it multiple time and didn't just stop at 'fail' it was clear that he was here to pass it, not fail it. MOT guys seem to want to fail cars at the slightest issue, thankfully IVA are a lot more positive. 

Then it was on to weights, and it turns out the scales weren't overly accurate (yeah I know, no real surprise!). The kerb weights were 300 front, 312 rear for a combined weight of 612Kg. I measured it as 588.6Kg. This unfortunately would come back to bite me, as it meant my design weights were too low, more on that later.

So it was on to the proper mechanical testing, up on the ramp. He acknowledged that it was well built and that I'd taken my time over it. He didn't comment on some of my 'creative' solutions, like the handbrake to brake pipe clamp. He did point out that when the handbrake was applied the cable does get a bit close to something, I need to check that as I can't remember what he said. It wasn't a failure point so I hadn't taken a note.

And talking of failure points, there were a few found here. The first was some missing bolts and a clamp on the exhaust. That one was annoying, entirely self inflicted and something I should have checked for. Easy fix though.

Next one was the fuel line as it passes the gearbox mount, it's too close. It's not touching, but as he said when the rubber bobbin moves it could touch the fuel pipe, so that's a fail. Completely fair, and actually not that difficult to fix. I just need to reroute the line over the top. I might need to move some of the chassis clips to accommodate it. 

Then the last failure from underneath the car. When the clutch pedal is pressed, the clutch lever contacts the brake pipe. A very clear fail, unfortunately without a second person in the garage I couldn't have found it. Again, a reroute of the line should suffice, and again another chassis clip move might be required. 

That was it for the mechanical side of things, so in the end I was actually happy. It wasn't the end of the faults though.

Coming on to the engine bay, again he was happy with how things had been put together, no questions on anything. He was training another guy so was pointing out a few things, all of them positive. Nothing to fix under the bonnet.

Interior projections flew through, he didn't even get his test ball out. He could see I'd spent time dealing with all the edges, and it turns out the exposed chassis member would have been a fail so I'm glad I added padding. He did bring out his seat height test tool, given I'd spent time getting the heights right it was clear that the seat height and the seat belt height were very above the requirements.

On to exterior projects. He picked up the side mirror front point, but his testing showed the same as mine in that it was actually a good radius. Again for the rest of the car it was more of a check, although he did put the ball inside the front grill to make sure he couldn't impact the rivets. I'd already checked that so nothing to deal with there. 

So on to the first fail on the outside, the number plate surround. I'd completely misunderstood the rules, I thought it would be tested with a number plate in place. Therefore I had left the edges as is. Turns out that's not the case, and even if the plate was in place it would have still failed. So I need to reprint that one. While it shouldn't be too difficult, the original number plate was done on a slightly bigger printer so I'm going to have to design it's replacement in multiple parts. 

He also visually checked most of the lights, but picked out the side repeaters as something that warranted more testing. I know why, it's because of the angle of the bodywork and the rear arches means it could have failed. A couple of chalk marks to highlight the required 5mm angle showed that it was perfectly fine. Again, I'd checked that myself but it's always worrying when it gets 'officially' checked!

Unfortunately the front indicators were too low, so that was failure number five. It needs to be 350mm off the floor, and he measured it as 325mm. It is measured to the illuminated surface, and he said that it's a common failure with Cobras. His suggested fix was to take off the lens, black out the lower half and have the indicator only work halfway up. That would be enough to meet the requirement. While that's good to know, I think what I'm going to do is move the whole lens up. Again probably a 3D printed bracket of some kind, that screws into the original hole and hides it. I might combine it with the side light to make it a bit more sturdy, I'm not sure yet.

Next test was the brake test, and that sailed through for both service and parking brakes. He was calculating brake forces using a pressure meter attached to his foot, working out maximum force first then working back from there. The numbers came out really nice and balanced, both from side to side on an axle and from front to back. The rears showed about half the force of the front which is good. This was also tested outside where he slammed on the brakes, the fronts locked but the rears didn't so again a big thumbs up there.

While he was outside he also checked the self centering (no comment there so I assume it was good enough for him), then the mirrors check. As with the rest of the car he acknowledged that I wasn't trying to take the mick, and that the three mirrors were more than adequate. A quick check and it was all good.

Then it was on to the noise test... and no problem there! I am not entirely sure how, but apparently it's within spec so I don't have to do anything. 

I think that summed up the day really, things that I thought would be fine actually failed, and the bits that I was struggling with weren't even highlighted. And I considered myself pretty knowledgeable on the manual by the end, I still got it wrong. 

There was one more failure waiting for me, the weight. As above my measurements were too low, and therefore so were my calculations. When it came to design weights, I'd put 361Kg front and 409Kg rear, and it turned out that they are actually 331Kg front (which is a pass) and 430Kg on the rear (which is a fail). I was in range of the combined weight, but messed up the front and rear balance. This needs a design change rather than a mechanical fix.

Overall a very good outcome, while I have six issues to resolve none of them are particularly challenging. One is five minutes with some nuts and a spanner. Two need a bit of 3D printing time. Two more need a pipe bender, and the last is paperwork. I should have them all resolved over the next couple of weekends. 

Wednesday, 4 February 2026

The IVA day befoe

Well, I don't think I've been this anxious or nervous ever, and I have two kids!! It's IVA day tomorrow, and the process started today.

I picked up the trailer at lunchtime, from All-fit in Lichfield. First impressions were good service, good price, I was in and out in ten minutes with a big thing attached to my behind. 

I got it home (which considering it's my first time towing is an achievement itself!) and started to have some troubles. First one was self inflicted, turns out my best laid plan of reversing in the open area in front of my house was a no-no, I just couldn't get it turned round tight enough. Fairly simple to resolve though, I simply took it to the main road and reversed from there. A bit further and a bit squirmy but sorted.

Next challenge, getting the car on to the trailer. Despite a couple of misses and close calls. I got it halfway up with no problem. And then it just went 'dink'. Turns out the car isn't heavy enough to push the trailer down and decrease the loading angle. And my car is simply too low. When I'm in the car the seat bolts going through the floor extend too far, and they just got hooked on the ramp. 

This was emergency fix number one, getting the car high enough to clear the ramp. Thankfully I could just wind the spring platforms up and that got me enough, it's probably a good thing anyway as I know the car is too low. The only thing is that it messes up the geometry (and possibly the self centering), and also the wheel guards. I've just measured the wheel guards again, they're 40 degrees to the front and 60 to the back, so still within limits. (side note, one of the spring platform allen bolts has seized, that will need to be sorted)

Then came problem number two, and it's related to the deflection as well. There is a small edge on the trailer, and the rear wheels just span against it. That was easily rectified, a bit more speed on to the ramp and it was sorted. I'll need to do the same thing for the journey back. 

So it fits quite nicely on the trailer;


I couldn't have used the next size down, it wouldn't have been long enough. 

Now problem number three. One of the tie down straps looks like it's gone ten rounds with something, and doesn't work properly. It ratchets ok so I'm happy it's safe, but to unlock it needs some encouragement with a screwdriver. It'll get me there, it'll just be a bit longer to open when I get there.

And then lastly the car looks very crooked on the trailer, so I put a jack under the back and hoiked it over an inch or so. At least now it'll come off the ramp straight. It should be pretty easy to line up after the test too, it fits between two of the grooves so I can see what I'm doing. 

I also put the jack in the back of the car, just in case...

Oh, did I say 'lastly'? Silly me... there was one more issue. As the car hasn't towed before, the electrical connections are 'suspect'. I've given them a wiggle and they're on now, but I can't get 100 miles on a 'wiggle'. I'll leave it for now and just hope they're ok, but as a backup I'm borrowing my brother in laws light board from his trailer. I know that works as that's what I used to test my electrics. I'll just need to fix it somewhere on the back of the car or trailer. I've got a pack of zip tie wraps in my IVA toolkit. 

The cover is on, it's looking like rain tomorrow but I'm still undecided whether to leave the cover on or risk the small amount of rain. Knowing me if I take it off it'll be monsoon season on the M5, if I leave it on it'll be ripped to shreds before I get to Kidderminster. I suppose either way it's on for the night. 

So it's a 5am departure, that gives me an hour of contingency/coffee time. Early night tonight, in the vain hope that I'll get some sleep. 

As everyone says, if it passes then yay, if not then I will have a list to work off. If it needs a retest I will be driving it, this whole trailer thing has been extra hard work I could have done without. Of course, if the DVSA hadn't closed some of their test centres, I'd only be going down the road instead of a 4-5 hour round trip!



Sunday, 1 February 2026

Final weekend of tinkering

I guess I'm doing this blog post just to ease my nerves and make sure I have everything covered. I really want it to pass, or if it fails then it can be an 'easy' fail.

Last update on the fuel tank shenanigans. I am 99% sure I've now resolved the issue. The tank inlet has a jubilee clip, a spring clip and some silicon sealing tape. In an ideal world any one of those should have sealed it, but this isn't an ideal world. The silicon sealing tape was a new thing, recommended by an LCB fellow builder. I've never seen it before, but it's quoted as being fuel safe and very effective. 

What I ended up doing is removing the jubilee clip and binding the end with silicon tape, with a flare butting up against the tank. I then put the clip back on. So I've got the spiral clip for the physical connection, the jubilee clip for the liquid seal, and silicon tape for the vapour seal. It's ugly but it's working. Once the car is on the road and I've emptied the tank a bit I'll rearrange things. And probably get a different filler pipe. 

Out of interest I also weighed the back of the car with the full tank. The corner weight is now 158.3 Kg, which is only 12kg more than the original weight. Actually, that makes sense. The IVA gives a method of calculation that means for my 25 litre tank I was expecting an extra 20 Kg of fuel. So I'm right on the money there.

Of course, I also weighed it with me in the car and it came out as 197.5 Kg. My design weight for Axle 2 was 406 so I've only got a little left for a passenger. Then again, the passenger weight will be more on the other wheel so again that adds up. 

Now the bad news. I did a noise test at the proper revs. I'd done one before at lower revs but that doesn't count. With max power at 6500, it needed to be tested at 4875. With an idle noise of 84.5, at the required revs it's 104.4. Given I need 99dB that's a little over. Oh who am I kidding, that's a lot over! I am hoping that most of that is my testing method and location. A quick Google suggests even the idle noise of 85dB is louder than a police siren and similar to a lawnmower. It really isn't that loud so I reckon it's the meter positioning and the quality of the meter itself. 

If the exhaust is too loud, I am limited in what I can do. Easiest thing would be to replace the silencer with a wider one, unfortunately there's not enough space. Similarly I can't do a longer one as I've got the exhaust end one side and the cat on the other. 

What I can do is repack the existing silencer, or more specifically add a DB killer with some fibreglass wadding. The problem is that I welded the exhaust together, so it's not a simple case of adding one. I guess if I'd have done the noise test a few weeks ago I could have had the time for one to arrive and for me to cut the exhaust and install it. So this particular one is in the hands of the IVA gods. I'll sacrifice a milky bar later on to see if that appeases them...

(The following day...) I've been thinking more about the exhaust again. Whether it passes or fails I will probably still add the DB killer, or do something to calm it down a bit. But at the same time I can add a flexi joint. I didn't bother initially as the consensus is a longitudinal engine doesn't bend the exhaust as much as a transverse. But it's not a huge deal to add one, I have space and it would make things that little bit more reliable. 

And one more picture. I wanted to follow up on the steering angle to make sure it was sufficient. It occurred to me last night that with an overhead picture I could then draw on some lines and measure the angle;


Using the angle measure in Powerpoint it should one at 351 degrees, and one at 3 degrees. So that's a 12 degree deflection between the two which is great. 


Wednesday, 28 January 2026

More fuel tank

Oh why did I say 'no garage'?!! I'm back with a smell of petrol in the boot, so lucky me I think I'm tracing another fault. The last few days has just been one long headache, both figuratively (trying to find the fault) and literally (because petrol is not a nice thing to breathe in).

So good news first, the tank is sealed. There is no sign of any issue from the seams, I've done umpteen pressure tests with soapy water and all manner of checks, but I can't find any leak. There was signs of spillage outside the tank that was showing up with the UV light, but after wiping them off there was nothing.

My attention then came to the filler pipe as that's the main thing that I'm worried about. It turns out I was right to worry, because a pressure test with soapy water round the end of the pipe showed bubbles. 

This leads me to two outcomes. First is that the weld to the tank isn't good enough and it's leaking there. Second is the pipe isn't sealing on the metal tube. I do need to do a better pressure test to differentiate between the two. I have been having trouble maintaining pressure as the fuel cap I have is only pressure fitted. It gets a bit difficult to use the pump, maintain the pressure and check what's going on. What I've done is 3D print a 'cap'; 


This will take the place of the upper filler neck and use a jubilee clip to seal inside the pipe. Then I can use the bike pump adaptor to apply pressure and more importantly maintain it while I check things.

I've also got some better clips on it's way. I wasn't convinced the jubilee clip was the right one, particularly for spiral pipe as it can't apply even pressure. I really should have paid attention to Car Builder Solutions when they had the proper clips alongside the pipe. Since CBS aren't particularly cheap or quick I've had to switch to Amazon Prime to get some proper clips;

The idea behind these is that it can work with the spiral binding of the pipe and apply an even pressure to clamp in place. They should be arriving today and maybe if I'm really lucky they will solve the issue.

On the other hand, if it is the weld on the filler neck I have bought some fuel tank repair putty that will be applied to sort any hole in the weld. Ideally I'd reweld it but I haven't got time to drain and wash out the tank, weld up, repaint and refit it, etc. 

So I am nearly there, it's been a panic week to get it sorted but there is light at the end of the tunnel.

In other news, I had three holes through the bodywork at the back for the reverse light, fog light and number plate light. All needed grommets so they didn't chafe. The number plate light was the easiest to sort, I just used silicon to keep the wire fixed in place and not able to rub;


The other two needed grommets, and they weren't going to be easy to find off the shelf parts. So I decided to venture into TPU printing! For those not in the 3D printing world, TPU is a polyurethane filament that stays flexible after printing. It's not as soft as rubber, the shore rating is around 95 so it's pretty stuff compared to rubber. However it does provide a soft surface to act as a grommet.

Admittedly it took me four attempts to get a working grommet, it would appear that shrinkage after printing is a huge issue. Given the hole is 14mm across, I had to print 16mm wide to get a tight fit. But they're both done now so that's the last of the wiring. I've been over every section multiple times and cannot find any potential failure. 

One more job done, sort of. When the car is on the trailer overnight next week, there is a possibility it's going to be very wet so I need a cover. I don't think I'll use it when driving down to the test centre, but I do need it to stay put overnight. I bought a few metres of ripstop fabric, and printed some roll bar sized clamps to hold it to the car;



I suspect a bit of wind might fold over the edge and let water in but it's a decent start. At least the whole thing won't come off and land on the neighbours lawn! I just need to design and print a couple more clamps for the front, but I'm hoping this will be sturdy enough to survive the night. 

I am watching the met office website, since they only do 7 days ahead I don't quite know what the weather will be. I am still hoping for dry, I'd say warm would be nice but it's February so dry is about the best I can hope for. I'll first find out Friday what the weather could potentially be, but then it's still another seven days of changes that are possible. 



Saturday, 24 January 2026

Fuel tank, geometry, brake testing

 The fuel tank is back in, and I've topped it back up to full. No whiff of petrol at the moment, although I'll do a sniff test in the morning after any fumes have spent the night building up. This time I've also kept some petrol in the jerry can in case I have to do any more work in there.

I also lifted the front of the car a bit. I'm very wary that the sump is less than 100mm off the ground. Any speed bumps (like the ones all round the village!) and I'm losing my engine. The front lip was also lower than 100mm, or at least it was. I've lifted the front so it will get over speed bumps, but the engine is still too low. I don't want to lift it too high because it'll upset the handling and geometry. So for the time being it's too low to get past speed humps.

The plan had also been to sort out the front camber as it wasn't quite right. But lifting the front actually made it a lot more even so I didn't have to tweak the camber in the end. The rear looks a bit cockeyed but I can sort that another time. A quick wheel alignment later gave me 1 degree negative camber and zero toe. What it did also give me was 'some evidence of self centring'...

Basically what I was doing was taking it up and down the road to get some heat into the brakes and see how they behave. On one of the turns I accelerated and saw the wheel turn back towards straight. Which means I'm finally in a position to have that 'evidence'. Lets hope it resurfaces on the test!

What else is there? Oh yeah, the brakes work well and consistently, although still feel a bit squishier than servo assisted brakes. However, I did get a front wheel to lock up which is mostly good. Of course it could have just been on gravel but it's better the front locked up compared to the rear. So again, that points to things behaving themselves. I didn't get the brakes hot, although they were the same temperature both sides so that again is a good sign. 

A small digression, I did check the gearbox rear mount and it's secure so that's all sorted. 

One last job for today was the front trim. It didn't seem as secure as it was before, that carpet tape seemed enough but not a long term choice. That's now been reattached using proper silicon so it won't come off. 

Overall a very positive day. Everything points towards a pass which would be fantastic, but on the other hand a fail is so much more likely. As long as it doesn't catastrophically fail I'd be ok with driving it for the retest. Although at that point it would definitely have to pass otherwise I couldn't get home!

No garage tomorrow, or at least no time on the car. I might get in the garage and do some tidying, but given the car is basically 100% at this point I don't want to jinx it. Next weekend I'll charge the battery and maybe run it up to temperature for one last time before the test. 

I did wonder about this blog and whether it would continue. Of course it will continue, isn't that the whole point of a kit car? Planning ahead the first task will be getting the car registered and driven for a decent distance. Then it'll be prep for the kit car show, the first time I go as an owner rather than a spectator. I wonder if I can get a boot liner sorted before the show so it becomes a functional storage area.

After that, who knows? Perhaps a move to a 6 cylinder something? A paintjob? Perhaps a rethink of an aluminium interior once I've burned myself on it when it gets sunny?

Oh, I do need a phone holder that is good for navigation. Getting to the Malvern showground is pretty simple, I used to work very close to it so I remember it quite distinctly. Problem is that's on the motorway, and this car is not a motorway car. I'd prefer to do the country route but I need navigation.


Friday, 23 January 2026

Fuel tank checks, interior padding

 As I've mentioned before, I had a fuel tank issue and traced it to the earth connection. This is what tracing a leak with flourescent fuel looks like;


Doesn't it look pretty?  As mentioned I removed the bolt, cleaned it up and just smothered it with Sikaflex to seal it;


I'm still a little frustrated that I didn't remember the earth lead when I was welding it up, then I could have added a proper tab. Actually, even when I repositioned the filler I could have added an earth tab! Ah well, 20:20 hindsight and all that. 

It's fixed the issue though, I can open the boot, stick my head in and smell nothing but fibreglass and tyre rubber. And Sikaflex.

Back to the interior and I've added a couple of pads to the required areas. One for the shin-basher;


And another for the steering support;


They're not my finest work but they will do the job. It turns out that velcro wasn't just a good idea, it was essential. Those pads need to be removable in order to remove the front panel and get to the gearbox. 

As ever I've got a few more jobs to do this weekend;

  • Retest and refit the fuel tank. I want to do one more pressure test but given there's no smell I'm not expecting anything. Oh, and I've bought some longer bolts for the straps, as I noticed the old ones didn't go through the nylocs far enough. That would have been a daft mistake.
  • Check the rear gearbox mount. I'm sure I've checked it before but I just want to reach under and check it's got nuts top and bottom. Again it would be a silly mistake to have one missing and I'm 99% sure I've checked it multiple times already. But two seconds with a screwdriver (or even a jack to go underneath) will be enough to check it.
  • The wiring issue behind the dashboard turned out not to be an issue, basically when I tightened the sleeve around the cables I accidentally dislodged the ignition switch plug. Once it was plugged back in it was fine. 
I need to start gathering paperwork as well. I've found the V5 from the donor vehicle so that's coming with me. There's the IVA4 declaration, which itself talks about photocopies of detailed receipts for the major parts. Given most of the major parts came from the donor I'm hoping that eBay receipt will be sufficient. The one thing that was a 'cash' deal was the steering rack, no receipt for that one. 

I also have receipts for the steel and the body itself, so apart from the seat fabric, consumables and 3D printer filament I think I have everything covered. And yes, given how much 3D printing went into this car I am tempted to describe it as a major part!!

Actually, while I look at this the one thing I'm missing is the nuts and bolts, I have receipts for those. It talks about 'original receipts may be requested' but given most of these are electronic anyway I suspect the intent is a little out of date. 

Carrying on with the IVA4 doc, it talks about photographs depicting the various stages of build. Now I was aware of this when I started building, and that's partly/mostly why I started this blog. What I sent to the IVA people was a 'build diary', showing photos from each stage. I'll print that out and take it with me. 

Less than a fortnight to go.


Monday, 19 January 2026

Last of the interior fittings

After going over the interior a stupid number of times, the last IVA question was around the visible chassis members TR9 and SW3;


They are exposed and while they will 'probably' meet the radius requirements I didn't want to go into the IVA with a 'probably'. 

After asking the question I wasn't seeing many responses. But it turns out the gov.uk website had some extra info. On their guidance notes page https://www.gov.uk/government/publications/individual-vehicle-approval-iva-for-cars-help-to-get-a-pass/individual-vehicle-approval-iva-for-cars-help-to-get-a-pass#interiorfittings, they have a picture of what is included in the test.


The problem is that this diagram and what is in the IVA don't agree. 

This shows items below the instrument panel and above the 150mm line are tested by the bigger sphere. The guidance notes assume that the instrument panel is long enough to reach the 150mm plane, but in my car it doesn't. 

So I'm back to doubting whether it's acceptable, and to remove doubt I'm going to add some padded surfaces. Looks like another trip to the Hole in the Wall in Walsall! 

What I think I will go for is some strips of aluminium with a suitable gap in the middle so they fold. On that I will glue some light foam then black faux leather on top. Then I'll have a soft edge one side, and hard aluminium to fix it in place. I think silicon again to bond it in place, it worked well elsewhere. I need to work quick though, not many days left. 


Sunday, 18 January 2026

green fuel

Yesterday I filled the tank up to the brim and looked to check. What I found was green fuel, and while I thought it was odd, I just assumed it was modern fuel with all it's additives.

I was actually completely wrong! A while back I added some luminous dye to check for leaks, and of course now I can see the tank full I can see the dye! And yes, it glows quite nicely under UV light.

That took me back to my original plan to look for leaks. I still have a petrol smell coming from somewhere and cannot find it anywhere. However now I know the dye has mixed properly I had another scan for anything glowing. Of course, there isn't anything that I can see so far. 

I did dismantle the pipe connection behind the seats as there appeared to be 'something' there. But given the pipes took a lot of effort to break loose, and there was no glowing going on, I just cleaned the pipe up and reassembled it. 

So I'm 99.9% sure the leak isn't from the joints or the pipes, which brings me back to the tank. A small job for today (once I've typed this up) is to unstrap the tank and lift it off the cradle. Fingers crossed I find something but I really am not sure.

Oh, something else I noticed. The black paint I've used for the chassis and on the tank is not petrol-resistant. I spilt some on the cross bar and it went very soft. This is actually a positive for me, because now I'm not just looking for the dye leaking somewhere. I can look for soft paint. 

I really don't want to be presenting a car for IVA that smells of petrol, then again it's going to have been exposed to the open air for quite a while before the test starts. If I found a leak I'd actually be happy because I could sort it, not knowing where the smell is coming from is driving me up the wall. It's definitely from the back though, when you open the boot you can smell it. It's not the same when you open the bonnet. 

Oh, and one other job I'm considering for today is a pattern for the boot lining. It should be relatively simple, and I still have a decent sheet of aluminium left (I think). A couple of folds and a whole load of rivnuts will get something in there. It won't go in for IVA but I might be able to set it up for the car show. 

2 weeks and several days to go...

(later that day...) so a bike pump, a fuel cap seal and the aforementioned dye shows that there was a leak. It was at the earth point, it hadn't sealed sufficiently. Since the whole point of the earth point is to connect metal to metal, it won't be possible to use rubber washers. A copper washer might have been enough but I couldn't tighten the bolt that much without stripping the thread. So I've put sikaflex all over the rest of it, and then sealed the top. Once it's cured I'll retest it. Thankfully because it's a flat panel tank it goes 'boink' when it's up to pressure, so I can see/hear what's going on. 

But I've gained another job for my to do list. I switched the power back on and didn't get any lights on the dash. Turns out I have a loose connection or plug behind the dash. Or it could be a dodgy earth. So I need to get back in there and see what's going on. That's all started since I added the protective sleeve, it was fine before then! 

Saturday, 17 January 2026

Camber and spacers: fixed

 The blocks got cut, welded, cleaned up and fitted;




I might tidy them up after IVA but just for now it's the biggest surface area I can use. The camber on both sides is closer to 1.8 so that's dropped a fair bit, although not quite the 'zero' that would have been preferable. The bolts went back on fine and everything is nice and secure.

A couple more things now for IVA. The fuel tank is full;

Although I really don't remember petrol being green coloured... I'll just assume that is all the detergents and stuff that goes into modern fuels. 

I also wanted to take a photo for the fuel hose markings;


R6 fuel hose is suitable for up to E15. This is a 15% ethanol which I would be avoiding anyway, not least because I don't think the engine would like that high an ethanol rating. The tank is full of 10%, I could go to 5% if it's not happy but for IVA it's good. Maximum fuel pressure is 50 PSI, with the Mazda fuel pressure regulator keeping around 43 PSI in the fuel lines. I think I'd have to upgrade it if I went for forced induction. 

Next thing, handbrake efficiency. While I can't test the exact numbers, I did test it by using my torque wrench at each click. From 0 clicks I measured how much torque is needed to turn the wheel each side. 1 and 2 clicks gave it a slight drag, 3 to 5 seemed fairly progressive. I did see the right hand side come on slightly quicker than the left but it doesn't seem significant. Then by the time it got to 7-8 clicks, I was tightening wheel nuts rather than turning the wheel. The Mazda original required roughly 7 clicks, so I'm happy with that. There's still reserve travel, and I could adjust it slightly if required, but I don't want the pads to drag. 

One of the last things I need to figure out is the visible chassis rails in the interior, as per this pic;


According to IVA they come within the 'specified zone', so must be 2.5mm radiused. Now, the natural curves on the corners are close to that, but I still have doubts on whether they need something covering them. To be fair, I've never seen those covered or padded on other Haynes roadsters, but they're probably a bit more exposed on my car. 

Is that it? I've gone over the car multiple times, and no doubt I'll go over it again for the next few weekends. 


Monday, 12 January 2026

Camber and spacers

 This is another of those jobs that started as a five minute fix and has escalated into something much bigger. Essentially I want to get rid of this;


The 'stack of washers' is on the rear suspension and is used to adjust camber. It's a pretty simple process, add washers to increase camber, remove them to decrease it. However I'm not going to be taking this on a track and chase lap times so there's no need to change it frequently. So I want to replace it with something a bit more stable. 

The mechanism will still stay as is, but what I want to do is reduce the leverage imposed on the bolt. It's probably overkill (and the 'unsprung weight' addicts will hang me out to dry!!) but I want to increase the surface area of the join between the two plates. There's no benefit to going larger than the smallest side (upper in the photo) so I'll make a spacer to suit that size.

The main issue is material, and this is where the worms started pouring out of the can. The current gap is 18mm, but I have no stock that thick. I can't use tube because it wouldn't be any better than the washers, and buying stock without the ability to machine to the correct size is a bit pointless. The biggest I have is 5mm plate, but of course 18 doesn't divide by 5 so I'd need something else as well.

Or would I? Now, I've not measured camber for a while, and now the fuel tank is 95% full it's a bit heavier on the back. So on the weekend I measured the camber front and rear;

  • Front left -4.3 degrees
  • Front right -1.9 degrees
  • Rear left -3.7 degrees
  • Rear right -4.2 degrees
First thing that jumps out is the front left, that's way too negative. That needs the upper adjustment to be opened up one turn. Of course, doing that I'll need to reset tracking AGAIN! 

The rears are far too negative as well, I'd prefer -1 or maybe even zero. The difference between sides isn't too bad so I can do the same process for both. 

But what is the process? Well, I simply need to round up! Given that I wouldn't have been able to make an 18mm spacer I have to use either 15mm (3 plates) or 20mm (4 plates). I'm not sure what that extra 2mm will give me, but it won't be enough to push it past zero. Best guess I'll end up with about -2 both sides which would be fine. 

So I need eight plates made up, which I'll then test fit to check, but ultimately weld up in a single block. That will ensure the bolt is only loaded with shear forces rather than bending forces. As suggested I'm sure Mr Champion will be turning in his grave when I add a seemingly innocuous block of weight, but at least it won't be coming off anytime soon. 

Just one last note, the possibility of rotation and unscrewing. It had occurred to me that tiny movements in the bushes on both sides 'could' allow the nut and bolt to unscrew. But the top wishbone isn't subjected to twisting movements which discounts that side straight away. The upright is subjected to significant twisting movements by braking, but that rotation is turned into linear motion when it gets to the upper wishbones (well, it's linear in two directions but the wishbone allows movement up and down). Obviously I'll keep a check on things but with various areas of friction, a really tight bolt and a nyloc nut I can't imagine this going anywhere. Even if somehow it gets loose it would still function as a wishbone. It would have to come all the way off (or snap), and of course the same could then be true of any other bolt or weld on the chassis. 

Over the weekend I cut a length of steel to 45mm wide, enough for eight plates. Hopefully at lunchtime I'll cut it into 65mm sections then drill through the centre of all of them. To keep them in line when welding I'll simply use a spare bolt to secure them straight. 

Thursday, 8 January 2026

Brake routing doubts

 As expected, the time between IVA application and the appointment itself is giving me far too much time to overthink things. This time it's the rear brakes. After trying multiple ways to route the brakes, I couldn't get to a point where the brake flexi and the handbrake cable didn't want to exist in the same time and space. Not without getting close to other moving parts either. Even I know a flex cable won't last one rubbing on a driveshaft or a wheel.

So I came up with a plan to clamp the cables together;



Given they're both travelling in the same direction when the wheel moves up and down, it made sense to me. This way instead of trying to keep them separate, I tightly clamped them together. The cables don't move inside the clamp so they can't wear. 

But something tells me Mr IVA won't like it, it's not exactly a conventional approach. I've pinged the question to the LCB crew to see what comments I got back, I suspect they'll also be displeased with my solution. Of course it might take a while as LCB isn't as active as it has been. 

Just looking at the photos above I was trying to think why it doesn't route downwards and come back up to the caliper. I have a feeling that the routing ends up interfering with the suspension. (Edit) Just going back on old photos I can see down isn't good



On the caliper side it interferes with the bleed screw and slide carrier, and on the chassis side that's roughly where the driveshaft needs to live.

The other option is to replace the flexi with a shorter one that has a right angle banjo, so it comes straight out from the wheel towards the chassis. That's possibly the best long term solution but there's a money and a time element to that. Getting custom brake lines isn't a quick task so I've contacted Furore to see what their lead times would be. 




Tuesday, 6 January 2026

Conduit and IVA photos

 Well, the conduit went on fairly easily, although it was remarkably sharp and extremely springy so by the time I'd wrapped it round the wiring my fingers were torn to shreds. It also appears that I took very few photos! This is probably the only one that I have


And this is only here because it's a photo of the gas cable clip. Here's a wider angle showing the position of the cable as well as more of the wiring and how it's pinned in place


Note the nut cover on the first photo, I am hoping that catching little details like that will demonstrate that I've really thought about the car. 

Other details now, this is the wiring under the dash


I often wonder why my engine bay has so much visible wiring, it's because most other builders have the bulk of the loom underneath the scuttle whereas mine is a bit more on show. I might hide it away perhaps, after IVA.

So yet more bits for IVA. First some photos, here's the roll bar bolts. Nothing spectacular here but I wanted to take photos of what was underneath the covers before I permanently attach them. Yep, they are now fixed in place with silicon which is 'probably' removable given enough leverage but they won't be coming off when the car is being driven which is my aim. I'd already tested for radius so I was happy the covers were doing their job, it was just whether they were secure. 



Using silicon for the corner trim in the cockpit has also improved things there, the corner trim feels so much more secure.

The next three photos show the uncovered transmission tunnel, this is mainly for IVA but I suspect the inspector might want at least one cover removed to see in person. 





Photos from within the tunnel again, this time of the hidden side of the fuel tank. If the car is up on ramps then the same can be seen, but I wanted some photos here to make sure everything is visible




This last photo shows the fuel pipe routing, I can't see another point where it can be fixed before it gets to the swirl tank so I'm hoping it's good enough. 

Seat belt bolts on welded plates inside the transmission tunnel. The rear fixings are visible from the wheel arch, the outer ones can be seeing by kneeling down. This is just to show the most inaccessible ones




What else has been done... I've gone back over my IVA application, and yet again flagged the challenge I had with the website. It's awful, I can't even go back into my application and look at what I had put! I had to start a new application (yes, my fifth application now!) and rely on the browser auto complete options to get the details I entered. At least now I can add the application details to my IVA build diary.

Oh yeah, the build diary. That's something else I'm putting together, basically it's a summary of this blog but in IVA manual order. I'm hoping that whatever questions the inspector asks will be to hand and get me that closer to a pass.

On the subject of getting closer, the trailer is now booked. I found a place in Lichfield that does trailers, I think with insurance for a 48 hour hire it'll be around £150. That's a Brian James double axle. I'll be picking it up lunchtime of the day before and returning it lunchtime of the day after. That means I can spend as much time as required on the day, without having to worry about getting the trailer back before closing time. I am still a bit nervous about towing, having never done it before, but I suppose there's a first time for everything. I've checked my breakdown cover as well, they cover trailers if my car breaks down, but not if the trailer itself fails. The trailer should be decent condition though, it's not as if I'm buying a lump of metal with wheels off eBay. 

Now, what's left...

  • I want to try and get the brakes hot to see if they're consistent. I might even try and get them to lock up if possible (fingers crossed the fronts lock first).
  • Similar with the handbrake, I want to check it works evenly across the rear wheels. This is a bit easier as I can do it with jack stands, I just need the current snow and ice to go away.
  • Engine light from the ECU. I wanted to see if there was anything coming from the ECU engine light pin, in theory there shouldn't be anything (and I don't even know if the 1.6 Eunos had an engine light!) but at least I'd like to check it. 
  • Front leading edge. It's the last radius edge I need to check, so two minutes with the 2.5mm radius and possible a file should resolve that. 
  • Fuel tank needs to be full. It's nearly there, I can see fuel through the filler pipe. One more jerry can of fuel will be enough. It's not going to be 100% full as the filler is on the side, but hopefully that will be fine. And I suspect some of the fuel will be used during the test.
So really not much, and to be honest if I was doing the IVA tomorrow I doubt the above items would matter. Not having a trailer would be a challenge but it's just hypothetical!

No doubt every weekend between now and February I'll be in the garage checking everything over multiple times. But I think for now there might be a pause in blog posts. Shame there won't be a similar pause in my anxiety levels, I think they're just going to carry on increasing as I get closer and closer to the day!




Wednesday, 31 December 2025

Extra job, wiring conduit

 I'm going to blame the MK IVA videos for this one! So far my wiring has been bound and clipped as required, but many of the IVA videos and other guidance have had the wiring in conduit. I've often thought it was overkill and I didn't bother. For the engine wiring it's in conduit as it gets from the chassis to the engine, mainly because that's where the most movement occurs. Where there's movement, there's possibly wear and breakage. 

All the way down the side of the car for the front and rear lights it's just bound wires because the wiring doesn't get any abuse as it travels. Now I'm in my 'overthinking everything' phase I am thinking for the sake of a tenner and a couple of hours effort it's worth just putting in some split conduit. All I would be doing is cutting each clip zip tie in turn, putting the wires in the conduit and strapping it back up again. The most challenging step would be the wiring in the side of the car where it's really awkward to reach. 

So yeah, I'm going to add that job to my list, as soon as I can find a decent length of 10mm conduit. I can't turn to Aliexpress, even if it's the cheapest it would take far too long to arrive. If I get it from Amazon I can have it tomorrow and get it fitted by the weekend. 

And of course, while I was just looking at the car, I found this;


The unsecured throttle cable that I needed to sort but have managed to completely forget about! That'll just need a 3D printed clip or similar to keep it away from anything metal. 

Right, Amazon shopping time...

Tuesday, 30 December 2025

Exterior projections / mirrors

 I have surprisingly few 'exterior projections' to deal with, a lot less than an average Locost or Haynes Roadster. With the suspension entirely enclosed that removes a whole load of work. Overall the only things that are considered projections are;

  • Lights
  • Roll bar
  • Centre mirror
  • Wing mirrors
  • Fuel Cap
  • Boot hinges and lock
  • Bonnet bolts

The lights were sorted a while back. They all comply as they are, except for the reverse and fog that needed rehousing. That's all done.

Roll bar needed a bit more work, the 3D printed covers do the trick though. 


Given the touch points of the sphere they're probably a bit overkill, but it was just easier to do them as one unit either side. The seat belt mounts are similar, and that's all that can be contacted.

The centre mirror was all over the place, it needed a full back cover to protect it. However that same cover also prevents the sphere from touching the lower fixing so no more needed there.



The wing mirrors were mentioned in my last blog post and also needed a decent amount of work to comply. 

The outer edge of the glass was less than 2.5mm so it needed something. The clamping bracket might have been ok but I didn't want to risk it. 


I'm happy with how they both came out. The ring around the outside is a press fit and will not budge, and the centre bolt bracket tightens up with the bolts. Ironically the 'pointy' bit at the front is compliant, and (just) meets the 2.5mm radius requirement


The fuel cap was bought as an OEM mini cap so nothing to be done there. Similar with the boot hinges, while they are contactable on all surfaces by the sphere there are no sharp edges to deal with.

The boot lock was a potential one, while the outer edge was rounded the underside and the bolting plate 'could' have been an issue. A quick sphere test shows the only part contactable is the outer edge so I'm happy that will pass.


And lastly the bonnet bolts, which I have covered before, literally and figuratively. 

I also did the floor line test today, as expected the rear and sides are of no concern but the bottom lip on the front constitutes the floor line. Having a quick feel along the front edge shows no particularly sharp points but I'll get the gauge on there and see if I need to give anything a sanding. That's all it will be though, I don't think there's enough exposed edge to warrant the push on trim. 

Another job completed today was the correct attachment of the interior trim, using silicon sealant instead of tape. I need to let it go off before removing the excess but I'm 99% sure it'll be secure enough to pass the test. 

I also need to let it go off to finish a job I remembered a while back, trimming the handbrake cable. I left it with a long tail so it's good to trim it to length now. I'll also take a few photos with the panels removed, I suspect Mr IVA will want to see inside the tunnel anyway but I'll take some photos as well.