So... I may have pancaked into the wall at COTA during 18hour race in the rain. The car drove like shit afterwards, but it also knocked the wing off... so i am not sure how much that effected it, but it had horrible horrible over steer.

i looked at everything and everything looks spot on... i didnt have a chance to string it because of some other issues, and now all the suspension is off the car.

long story short, in everyones experiance, what goes first in the rear?

 

The knuckle will bend first. I bent my knuckle just going off hard into the dirt. Couldn't see or measure a difference but a new knuckle fixed it for me. I could only get -1.5 camber after the off. With a new knuckle I could get back to -3 with room to spare.

 

Interesting, thanks.

 

You can obviously see if the suspension arms are bent but a bent knuckle will be much more difficult to detect. With "horrible oversteer" most likely your alignment was out so the knuckle is probably bent. Too bad you couldn't measure the alignment before you disassembled the suspension.

 

I've also had issues with a bent knuckle and getting another knuckle used off a wrecked car that was bent. Normally the way to tell is when you set it to the camber that you want and you can't get back to the toe setting that you want with the OEM adjustability.

 

It is possible the hit just moved one of the suspension adjusters and the knuckle is ok, but for peace of mind it's probably a good idea to just replace it. Carefully inspect all the arms and joints too.

 

All my adjusters are paint marked and nothing moved.

Are Ap1 and AP2 knuckles the same?

 

They are not the same. Different part numbers. I think either one will bolt up but you want to keep the geometry correct by getting the correct one.

 

If you're feeling really adventurous you could try heating up the bent section and bending it back. I would build a jig that constrains all the other fixed point very rigidly and then get creative with a hydraulic jack or heavy screw jack or something so you can move the offending part controllably. If you wanted to you could even bend it in a fashion that changes your geometry to what you want, ie more camber or something. All the old hot rodders did stuff like this all the time.

 

I think the parts are all cast. I don't think I'd go heating up mission critical suspension components. If It's a race car you should invest in spares and compare suspect parts to them. Should probably look into magnafluxing parts that take a hit too.
IMHO