Continuing with the process

 Start with an easy one, the brake fluid sticker;

And the front grille is now compliant (and in my opinion looks really ugly now);

Staying with edge trim, the centre tunnel is now compliant;

As well as the last few bulkhead bolts;

And lastly the handbrake bolts;

That picture shows that I've got two more covers to do. First is the handbrake adjuster, that's an obvious one. The other is the steering column support. Given the exclusion zone around the wheel it's really touch and go whether it's within range, so to avoid doubt I'll just do a clip on rounded cover. 

New month, same IVA work

I have a plan. I want to get the IVA done before the Malvern kit car show, but November/December are typically busy times for me and the family. So I'm going to put my application in at the end of the year, and hopefully get a January/February test. On the (hopeful) assumption that it passes, that gives me time to get it registered for it's first long trip. 

On that note, more IVA stuff. The interior edges are going well;

I've got the two outside edges on there. The tape certainly seems to hold them on securely, I just hope it's enough for IVA. I do need to test the seat movement with all edges in place though, just in case they get caught and torn off or something weird. That ended up with a 7mm diameter so 3.5mm radius, well in spec. I just need to do the tunnel edges next.

The suspension bolts now protrude from the nut an appropriate length, and I also got a washer in there for good measure;

There's still the stack of washers in between the suspension bars, I think it's ok as they're in compression but there's a possibility the IVA man won't like the design and I'll have to replace them with a solid piece. Of course that is the long term plan but only after I get the camber set correctly. 

The handbrake cables are now secure;

To be honest I think I've gone a bit overboard with them but as with everything IVA I'd rather go overboard than 'underboard'. 

The steering got sorted too. The background to this was that at full droop and full lock the steering arms were hitting the suspension arm. This isn't necessarily a fail as the test is done at static load rather than full compression, and they don't touch at that point. But again (most of) the IVA rules are there to cover issues, and this was an issue. It's a simple solution, I'm back to steering limiters. So now rather than nearly three turns lock to lock, it's only two turns. If you remember I'd put the limiters on a while back but they limited the steering to about 1.5 turns which is unusable on any road. It didn't take much tweaking to get them to where I want them. 

Away from IVA, I thought some stickers might be good;

And because I've now finished everything suspension related the hubcaps were added. I have to admit I think they could benefit from some paint, the matt black looks like a failed photoshop edit!

What's left now?

• Covers for the front grille. The one edge is too sharp so it needs a cover. A quick session with a ruler shows that I have 8mm clearance on the face before it gets to the rivet. It's only about 2mm deep before it gets to mesh, and it's about 25cm long (so two prints again. I'll modify the existing one, it'll have to be quite bulbous to meet the curve requirements but avoid the mesh and the rivets. 

• Handbrake covers
• Wiring final touches.

Hmm, that is an impressively small list! I think there might be one more job... complete the IVA paperwork. I might as well crack on with that. 

IVA work part five

 The front castle nuts now have pins;

And the wheel axle nuts have been 'staked';

Brake clamps worked really well and keep everything apart/together;

(I also turned the fuel pump connectors round here as I could see there was a potential chafing issue)

The handbrake cables still route against the chassis so I need a bracket or clamp to secure them;

I doubt a car could ever wear through a handbrake cable in this position as they're basically a steel tube, but having it fixed in place is a pretty simple task.

Steering wheel got de-radiused with a printed face;

I quite like it to be honest, the plastic just needed a bit of warmth to get the curves on either side and the bottom. It could probably do with a tiny bit of refinement on the top edge but it's IVA first, decorative second.

The boot lock got a split pin at the same time as the front axles;

That's not going to slide open anytime soon. 

One small but time-consuming job was reprinting the shells for the fog and reverse light to make sure the radii are ok;

So that's a few jobs ticked off, but of course I couldn't end the day without adding an extra job! The rear suspension adjustable bracket doesn't have enough exposed thread through the Nyloc nut. 

This is because these are still in 'adjustable' mode, hence the number of washers. It's the same inside the head of the suspension;

So really all I need to do is remove some of the washers so the bolt gets a proper distance through the nyloc. I'm thinking two or three washers will correspond to two or three exposed threads on the bolt. Only problem is that it's on the back of the car which doesn't have much space in the garage, I'd need to get it outside to fix it. Saturday is looking bright enough (albeit very cold!). 

The final to-do list?

 I've now gone through the IVA manual line by line, and these are the gaps I have left;

• 01 Noise.

Must have a measured sound level not exceeding 99DBA. I have actually measured this but it wasn't at the required revs and the engine was cold. I could do with doing this again just to make sure, hopefully the neighbours don't mind. The first time I think was around 91 so I am hoping I'm well within the limit.

• 02B Metered emissions.

The emissions limits must be met. Nothing I can do here, as with regular MOT's I can just hope everything looks fine. 

• 05 Steering effort.

The steering angle must not be limited by any part of the steering, transmission, or suspension system unless the components have been specifically designed for this purpose. Steering components must not foul or be likely to foul other parts of the vehicle under normal operating conditions. Basically I need to put the steering limiters back in, because otherwise the steering hits the wishbone. It's only at full droop, and the test is done with the vehicle at rest, but no point having it do something it shouldn't. 

When the vehicle is driven at speeds above 10mph, there must be a degree of steering “self-centring” evident. This to be retested now I've reset the suspension.

• 09C Park Brake control.

A parking brake lever, actuating linkage, cable or associated component mounting / bracket must be secure to the vehicle structure. I need to make clips to hold the handbrake rear cables to the chassis, otherwise they could be seen as touching and potentially damaging.

• 09D Hydraulic systems

An indelible label must be affixed in a visible position within 100 mm of the filling ports of the fluid reservoirs to ensure that it is possible for the end user of the vehicle to identify the brake fluid used in braking system. I have the sticker design, just need to print and stick. 

• 12 Interior fittings

Handbrake and mechanism to be assessed for contact. The nuts/bolts/edges etc just need the various covers on them. And yes, I still need to protect the wiring as it enters the car.

Edge trim on all edges. See previous post. 

• 16 Exterior projections

Check front grille metal edge is at least 2.5mm. The corner trim has made me paranoid that part of the front grill isn't correctly radiused. If it isn't then an extra bit of trim is required.

• 25 Headlamps

Headlight aim based on dipped beam. This sounds and looks really simple to check and adjust, but my garage isn't square on with the drive, so I actually need to do some rearranging in the dark to get this right. 

• 44 Masses and dimensions

Calculate design weights based on kerb weights plus passengers plus fuel. Measure length and width. This is for the registration form as well. 

In terms of corner weights, I managed to do it properly, so here it is;

Front left: 144.2 KGs

Front right: 144.9 KGs

Back left: 152.8 KGs

Back right: 146.8 KGs

For a total of 588.7 KGs. I am very happy with that, I thought I was closer to the MX5 donor car but turns out I'm 400KGs lighter. 

There are a couple of caveats to that. The tank only has a few litres in it, and it's a 27 litre tank. So based on the IVA values I can assume maybe 20KG of fuel to go in. I also did it per corner, with lifting the other three. Apparently it's a valid method of measuring, but I want to be overestimating the total weight rather than under. 

What I can't figure out is how these numbers relate to kerb weight, axle weight, gross vs max, what is permitted, what needs to be declared etc. I'll have to check the IVA form to figure out what numbers are actually needed.

Corner trim

 One thing I had forgotten was that the interior trim isn't IVA compatible. For some reason I thought about it a while back but then 'stopped', on the mistaken assumption that the aluminium trim would be fine. But now I need to sort out some trim to fix it.

The side trims are 655mm long and are 20mm tall and deep. The middle tunnel is made up of three sections;

• At the back the section is 345 long, starts at 247mm wide and ends at 172mm.
• The middle section is 490 long, starts with the 172 as the first section, then ends at 173. Not sure how that happened to be 1mm wider but there you go. There's a gearstick in this panel as well but hopefully that won't affect things. 
• The front section is then 173 wide, then expanding to 310, 367 long. 

My first thought is to print some trim sections. My printer can do around 250mm diagonally. So each section would have to be done in chunks. The sides would need to be done in 3 sections, the middle section could just about be done in 2 sections per side, the front and rear would fit no problem. 

Now I do have some options regarding material. TPU would be the most sensible, a bit of a rubber like texture would make sense. But it only needs to be rounded off, not necessarily soft, so I'm going to start with PETG as a test piece, and see how it works.

I do need to consider the screws though, they need to be left exposed and the edge trim worked around it. 

(Later that day)

I've made a couple of designs to print. First was a 20 x 20 trim. Apart from it not being able to stay attached to the bed, it's just too big for what is needed.

The second option is a 'hockey stick'. I've got a couple of designs of hockey stick, but I think tonight will be sorting bed adhesion and temperature. I've got some nice matter PETG but it's a 'high speed' filament so it looks like it's being cooked by the temperatures I used for regular PETG. The original setting was 255, I've dropped it to 230 which hopefully should help with the stringing and adhesion. 

And it looks like it has, the surface finish is much better. I just need to check how it looks on the car. 

(the following day...or two)

So I settled on a corner trimmed based on a 7mm diameter (so 3.5mm radius). It's a bit bigger than the hockey stick in both directions but I think it'll stick better. And yes, it will be stuck using double sided tape, although it will be pretty strong stuff that is normally used for holding carpet in place. Because of the size of the printer the six parts above are needed just for the outer edges, I need another ten for the centre console. I've only done these six for now, just in case I can't attach them properly. They need sanding, trimming, gluing together as one piece, then mounting on to the car. 

IVA work part four

 This morning started well, AWS seems to be poorly and most of my work is Amazon based.. thankfully this blog isn't so I might as well update from the weekend!

First thing, the brake pedal wiring. This is where I had left it;

I couldn't figure out where to route it that didn't come into contact with a sharp edge or a moving part. So I went for a mounted tube;

It goes from the switch bracket up the back of the bulkhead, secured with a wiring clip. That got the wire into the air, where it was then cable tied to the speedo cable, the chassis and ended up above the steering column with all other wiring. This was swiftly followed by a minor concern when the brake lights didn't operate, but I think I'd just dislodged one of the pins in the connector. 

I also rerouted the main power wires just to get them more out of the way so I could then tie wrap them in place. So now the drivers side footwell is all clean and tidy. I've still got some nut covers to go on for the radius check so that's one thing on the to do list.

This also sorted a binding issue with the brakes. The last few days I felt the car was 'heavier' than normal, it turns out I'd fitted the switch back a little too tight and it was holding the master cylinder on. I backed it off and then found the pedal was loose!! So I needed a bit of trial and error to find out where the switch held enough pressure to act as a pedal stop, not enough pressure to move the master cylinder, but also the correct distance for the lights to come on when they're meant to. That's all present and correct now so I'm happy. 

Next job, ID plate;

£8 from the local market key cutting van and a couple of rivets. It looked so good when it was on though, it was saying that this is my car that I had built.

Next, gearbox wiring. There are four wires that go from the loom to the gearbox. Two for the reverse switch and two for the neutral switch. Up until this weekend they were just loose single wires laid on top of the gearbox and I knew they would fail. Given there was a decent length on them and relatively easy access I just put them in some corrugated tube and pinned the tube to the chassis.

The tube goes all the way to the engine bay and is terminated on another tube so everything is protected. 

What else? Oh, the steering wheel. After a comment on a Facebook post I went back to the IVA to figure out what was needed on my steering wheel. Here's the wording;

• The rim of the wheel should be padded or at least made from a material which when deformed does not splinter or fragment. That's a simple one, I'm using the standard steering wheel so while it doesn't feel padded, it isn't going to splinter or fragment. I'm guessing they're referring to wooden steering wheels here.
• The centre boss should be padded or recessed below the level of the rim. This is the main one, I was working on it being 'padded' but there is the 'recessed' option which it is by default. So as long as I interpret this the same as the inspector I should be fine as is.
• Wheels with a very deep dish are stiffer than flatter wheels and, as such will absorb less energy. Not applicable.
• The centre boss will often be of a collapsible type comprising a convoluted crushable section or a series of metal fingers with a deliberate fold introduced to initiate a collapse. Yep the standard boss is of this design, it's inside a corrugated cover but it can be seen with the horn button removed. 
• Bolts used to secure the wheel to its boss (if exposed) should ideally be flush with the wheel surface but otherwise are required to meet the radius requirements if contactable. Yep, flush mount allen bolts. 
• Bare metal spokes are allowed as long as they conform to the edge radius requirements. This one is currently a fail, I've just checked and I'm not convinced they're correctly radiused. So at the very least I'll need a rounded face on the wheel, a simple 3D print should suffice. I did consider the bodywork edge trim but the wheel is too thick and too close to the boss to allow correct fitment, so a rounded printed edge will have to do.
• Components likely to catch in the driver’s clothing or jewellery are not permitted. Not applicable.

So I can go for less of a padded wheel and more just a cover. I'm kind of glad because the padded face wasn't going well. The only thing I would need to do is label the horn, so I replaced the 'momo' badge with a 3D printed version;

It's not bad, I'll have to wait and see whether I like it enough to keep it after IVA or go for some other button + label. 

I think I mentioned this last update, the fuel pump wires now have the proper covers on them. just putting it here in case there's a problem seeing them at the test.

The reflectors I made earlier in the week are now glued in place so that's that job done.

The seats are now properly bolted in with nylocs and washers. They don't have huge spreader washers mainly because there's a layer of aluminium, a steel insert in a steel tube, two thick washers and the seat sliders between the two ends of the bolt, a wider washer wasn't going to do anything. The seat rails work well, the drivers side is a bit stiffer than the passengers but I suspect that's just old age. Not that either one will be moving very far, I doubt anyone will be driving my car! Oh, apart from the inspector of course, apparently that's a 'thing'. It makes sense, it's not as if he'd be able to pick up on self centring by watching me drive it. 

Last thing is the suspension geometry. So I dropped the front end until the suspension was as horizontal as I could get it (the body nose is now vulnerable to speed bumps but I'll have to figure that one out another time). The tyre pressures are up to recommended values, and I've reset the front toe to zero. It was actually quite a bit out, partly because of my tinkering but mostly due to the suspension lowering. 

So time for a quick review of the job list;

• Lock the wheel axle nuts. They've been done up to torque, I need to give them a clout with a chisel to lock them in place.
• Lock castle nuts. Similar locking needed for the castle nuts, split pins are the order of the day.
• Replacement fog and reverse light shells. A much appreciated comment on Facebook pointed out that the outer shells of my 'IVA friendly' lights are in fact quite sharp edges. It's a little bit annoying but absolutely right. So I've got a replacement drawn up and ready to print. As there was already a printed section to put it at the correct angle, I put that back in with the new shell. I just need to wait for some filament to arrive and then 5 hours per side to print them out. 
• Door roundels to go on. Not really for IVA but I want to get them on anyway. 
• Nut covers for the handbrake bolts/nuts. 
• Securing pin for the boot handle. While the boot does close and lock pretty securely now, the lock itself is only a friction fit on the handle. It wouldn't take much time/heat/vibration for it to work itself loose. I want to back it up with a hole through the shaft and a split pin to keep things in place. Not a difficult task but it needs to be on the list. 

Photoshoot

 Decent weather plus 99% finished car means photos!

MX5 NA fault codes

 I'm putting this here as I've finally found an appropriate collection of information that will help now I have reinstated the diagnostic port. I originally removed the port because I thought it just gave the ability to check various voltages in the circuit. Given I'm not working on an original MX5 I figured I could just check the actual wiring. Unfortunately it's got a couple of extra pins that aren't replicated anywhere else.

First option it gives is setting the base idle. Given that I have a slight idling issue I thought this could come in handy.

Connecting the TEN pin to Ground using a piece of wire removes the ECU control of the idle speed and leaves it entirely up to the throttle body. On the throttle body itself there is an idle screw, it's in a short cylinder and sometimes covered by a rubber bung (mine isn't which is a bit worrying as it suggests someone else has already had a go at it). 

With all electrics off, the engine running and up to temperature, connect TEN to Ground, then adjust idle to get to 850-900 RPM. Then remove the connector. Nice and simple

The second is some fault codes of sorts. It's not a posh OBDII interface that requires a dongle or similar, it's more like the old Vauxhall option that I remember from when I was a kid. 

With the engine off this time, connect an LED (with current limiting resistor) from the FEN pin to the battery. (Or in my case as I don't have a battery connection immediately available, spend at least ten minutes trying to find an accessible positive which could be entertaining as the IVA required them all to be covered and protected!). Turn the ignition on and look for the LED lighting up for five seconds (if it doesn't, it's backwards, however considering I'm connecting one side to battery I'm going to assume that's the positive on the LED).

After the initial check, it should flash any error codes as below;

• 1 Ignition pulse
• 2 Ne signal [Crank angle sensor]
• 3 G signal [crank angle sensor ground?]
• 4 SGT signal (1.8L)
• 8 Airflow meter
• 9 Water thermistor
• 10 Intake air thermistor in airflow meter
• 12 Throttle position sensor
• 14 Atmospheric pressure sensor
• 15 Oxygen sensor (output too low)
• 16 EGR function sensor (1.8L)
• 17 Oxygen sensor (output not changing)
• 25 PRC solenoid valve (1.8L)
• 26 Solenoid valve (Evaporative canister purge)
• 27 EGR solenoid valve (vacuum)(1.8L)
• 28 EGR solenoid valve (vent)(1.8L)
• 34 Idle air control valve

For the two digit codes, it flashes the ten's digit first with longer flashes, then pauses before flashing the one's digit with shorter flashes). It loops round the codes so it can be double checked. 

For my car I'm expecting at least some codes, for example the evap canister isn't there anymore so '26' is almost guaranteed.

Lastly the diagnostic plug pinout with the relevant coloured wires. This was built up from various sources on the assumption that I had binned my diagnostic plug and I was going to have to come up with another solution. As it turns out, I still had my diagnostic plug with at least the important wires still attached, but at least this list would have given me an alternative;

• 2. LT GRN-YEL to Conn#1 K (ignition adjustment connector) (TEN terminal) Test
• 3. WHT-GRN to Conn#1 D (Data link) (MEN Terminal) Monitor
• 4. WHT-YEL to Conn#1 F (Data link) (FEN Terminal) Faults
• 15. BLK to GND
• 17. WHT-RED to Conn#1 B and Power and Fuel injectors (engine control relay)
• 18. GRN-ORG to Horn Relay
• 20. BLK-GRN to Cooling Fan Relay
• 21. BLK to GND
• 22. YEL-BLU to Igniter
• 23. RED to airbags

In my case I've only got the first four, as mentioned the fifth wire for battery might have been useful but I can live without it. 

So that's a task for this weekend (or maybe one evening this week). Work has been ridiculous though so I've not had chance to do any work. I'm even typing this while watching something process at work, just because I've not had any other time available. 

IVA work part three

 A few more jobs ticked off this weekend. The bonnet catches are now installed with a cover on the outside;

The diagnostics plug has been wired back in and is ready for use. (OK, not strictly IVA but checking the engine is running properly will help with emissions).

A couple of sections of wiring loom have been fixed better;

In both cases it was a cut strip of aluminium with a hole in one end and a couple of layers of heat shrink tubing. Bolted in place in any convenient location then bent around the wiring loom. It's a similar approach to what car manufacturers do so hopefully it's IVA compatible. 

The loose fuel pipes are now on a secure bracket;

Although I now need to bind and route the cables that go over the top. 

The chrome trim is on the headlights;

I think these look amazing and really finish off the front. No more spiky screws showing!

And for the rear, I've made up some reflectors;

I couldn't find any that fitted the space properly, the ones that I ended up buying were way too small to look good or pass IVA. These are a couple of trailer reflectors, cut to size and trimmed with a 3D print. The flash picture shows they do their job, and I preserved the E marking as well (although I think cutting them down would have invalidated the marking).

The fuel pump now has covers over the connectors, I had some that came with the pump and they turned up on the weekend so I fitted them. No pic though, it was dark. I had planned to 3D print a cover but using the proper ones made more sense. 

Talking about 3D printing, the brake pedal switch cover was a mixed success. The first cover looked good but it put the wire into the clutch pedal so that was useless. I reprinted it with a tighter bend so now it avoids both pedals;

But I'm having trouble routing the wiring up and out. Because of the gas pedal swinging from the top, I can't route the cable directly to the exit. I've printed a tube to get it up above the pedals, but I still need to consider where it's heading after that. 

And I've still got to deal with this;

I can see a few different things here. First is the run from the chassis to the rear bodywork, it's a connector in free space so I need to support that somehow. The curve on the left is self supporting so that can stay. The hoop in the centre of the picture is just the brake pedal switch wire so that will get sorted when I figure out the routing above. Then it's just the main block with the two connectors on board, they need a support of some kind. If I build a 'shelf' for this and the rear bodywork then that should take care of both. Then I want to think about panelling it in, just so it's not exposing the driver to road debris.