[DriveHard]

This is what i got out of one of the bolts on my car.

all dimmensions in mm.. line drawing not to scale ( but close LOL )

There is a washer that is captive to the un threaded shoulder of the Bolt. it is 2mm thick and 21.4 mm wide with at least an 11mm hole

The bolt appears to be Zinc plated ??? I am not sure, but it does not appear to Rust and is silver / grey in color.

See picture below.. I tried looking locally MSC, McMaster, Grainger but i could not fine one that was available on line with all the necessary artributes. I did fine one un plated though with no captured washer.

I will forward to Eric at SupremePower as he said he might be able to still help.

for those hunting, let us know if you find something..

when looking you are looking for a bolt 70-75 mm long ( length from under the head to the end of thread) if you go 80mm you may hit the backing plate on the top bolt

p.s. under a magnifying glass, my bolt shows no signs of streatch / wear/ crack etc .. It has been off and on at least 6 or 7 times, hot, cold, at the track and in the shop.