Wheels and shocker mounts

For a while the car had been suffering from vibrations around motorway speeds, I thought it was something up front as I could feel it through the steering wheel, but after watching the rear wheels on the rolling road it was possible to see that the wheels are nut running true. Some time this morning was spent first checking the hubs for run-out and then the wheels. Spinning the wheel over by hand you can the the wheel and tyre more in and out, at worst according to a dial gauge, 2mm.
To prove the point, the standard steel wheels were fitted, they run much more true and do not give vibrations at motorway speed. I reckon when the alloy wheels were re-furbished they did not take into account the thickness of the paint on the area where the wheel mates to the hub, so one side of the wheel is further out than the other. You can see on the inside of the wheel that it has not been contacting across the whole surface area. I removed all of that paint so it will sit flat again. They were fine before they went in, but the new paint is much thicker and having done this the car felt a lot smoother.




Following suggestions on how to make the car drive and feel better, wheel shims have been added to the rear. I started with 25mm spacers, but the studs supplied with them did not leave enough spare thread as I wanted, so the spacers were reduced down to 17mm. This means the car has a slightly wider track width than the later Spitfires with their long driveshafts, filling out the rear arches much better and noticeably improving the handling in corners.

Image on left with spacer fitted




Then a couple of weeks ago I noticed that the shock absorber top rubber was trying to escape, correctly diagnosed by charlieb as being due to the way the springs are now supported, meaning that these rubbers are now taking the weight from the spring also.




To get round this I have for now at least, fitted some re-enforced rubber washers cut using hole punches. Hopefully these should hold up better until I do something like copying Daves top mount idea incorporating rod ends.