Suspension thoughts

Now that the chassis is actually taking the (sort of) form of a car, it's time to start looking at suspension. So first part was the brackets and the bushes.

The brackets are on their way from Dave at Rogue Engineering, £1.50 per bracket and money for shipping. I did look into possibly making my own (no method of bending unfortunately), or even buying some hollow section steel and cutting a face off, but it would have been a lot more effort for not a lot of saving, so £42 total price for the brackets was the way I went.

Bushes were much easier, another Ebay search revealed a set of 22 crush tubes and 44 bush top hats for £50. Again, as with the brackets, I did look into DIY cheaper options, but the effort and accuracy made this purchase a much better option.

So, on to the suspension wishbones. These are definitely a DIY job, for example Talon Motorsport asks for £300 for a full set of wishbones and I was hoping to build most of the chassis for that! There is also an additional problem...

The Haynes Roadster measurements are based on a Sierra donor, and I don't want that. I decided early on to use a Mazda MX5 as that was a proven alternative with only a few subtle mods. For example, the front wishbones are virtually identical to the Sierra versions, with the main difference being the top ball joint having to be sourced elsewhere. That shouldn't be too difficult, it's either a 3 series BMW ball joint (which one is TBC), or ream out the Mazda upright to suit the Transit van ball joint from the original book. No problem for either of those.

The main problem is the rear suspension. The Mazda alternative is based on the huuuge rear diff cover that the Mazda uses, but it results in the upper wishbones being a significant compromise. And basically, I don't like them. What I'm going for is a replacement diff cover from Talon Motorsport, that fits more like the Sierra diff and allows for 'normal' wishbones and a more standard back end to the chassis. It does appear that I'll be treading new ground though, so I need to do some calculations on how long the wishbones need to be in order to use the Mazda uprights but the 'Sierra' wishbones. Not a huge problem, but it's a task that will need to be completed before I build the wishbones.

I'll also need to understand how Talons diff cover is put together, there are mounting holes but they don't line up with any existing design so that'll be another custom task to do.