Can anyone give me advice on how to get rid of bumpsteer on my pinto engined indy please?

get your caster/camber checked as well as your tracking a proper garage not a kick fit type place

There shouldn't be any bump steer on an Indy - the rack should have been specially shortened to suit.

What makes you think you have bump steer?

Cheers

Mark

How are you checking that you have it ?
when the vehicle is static,with the wheels in the straight ahead position,and the steering rack centralised,IE same amount of rack sticking out each side of the rack body.
When you bounce up and down on the car, the wheels will toe in and out as the suspension rises and falls,if you have a lot of bump steer it will be clearly be visible,by a large amount of movement toeing in and out of the wheels as you bounce the front end up and down.
To erradicate it best as possible the rack is best positioned as close to the top or bottom wishbone.( the top is usually prefferable ) When you have decided which is most feasable,ideally the ball swivel on the steering rack arms when the car is in the straight ahead position should be directly above or below the centre line of the top or bottom wishbone bolt in a vertical plane,also when the car is at its normal ride height sat on the floor, you will need to measure that the gap between the wishbone at the inboard and outer end,between the steering arm and wishbone is the same Ie they are at the same angle running parallell to each other.
Then the steering arms will go pretty much through the same arc as the wishbones,this should then illiminate the bump steer.
I made new steering arms for my car to bring the track rod ends and steering arms up to the right height,to make them run parallell, also had a custom rack so when my wheels are in straight ahead position,the steering arms swivels are directly below the wisbone bolts.

Hope it makes sense these are the general ways to sort it my car has virtually 0 bumpsteer now and has improved the drive and handling.

Good luck.
U2U me a tel. number if you want and Ill talk you through it.

Thanks Simon.

Mark,
the reason i think i have bumpsteer is every time i hit a bump or rut the car pulls all over the place.the faster i drive the worse the wandering.
Andy.

Before you start looking at bump steer, the symptoms you describe would suggest your tracking is out. Have you had the car tracked properly?

Bumpsteer is caused by your steering arms following a different arc to your wishbones. If you imagine drawing a line through your top and bottom wishbone pivots, your steering arm pivots should also be on this line, if that makes sense.

Phil

[Edited on 8-3-08 by Hellfire]

thanks Phil, i will have the tracking double checked. regards,
Andy

It sounds a bit like you need to also have a look at your damper settings - it feels down right dangerous if you hit a bump and have them set too 'soft'

Cheers Mark

I had terrible bump steer on the Indy that I bought. There were two problems with it, first the tracking. But by far the worst problem was the position of the steering rack.

I took the shocks off and did the laser trick to check for bump steer and it was horrendous.

I went down to MK and had a look at the chassis they were building and it would appear that the one I got was one of the earlier chassis and the position of the rack mount was very different. So I hacked out the rack mount and re welded in a more appropriate place (using the laser trick).

It has transformed the car from an evil handling monster that I though was going to kill me into an easy to drive riot.

hi andy when u built your car did u grease your suspension bushes. i did not grease mine and they wore very quickley giving the same symptoms as yours. when i changed and greased them it made a massive differance

thanks to all members who offered advice on my bump steer problem,it is now sorted.the main problem was the position of the steering rack (to low).i repositioned the rack about 10mm higher, reset the tracking and regreased the bushes. my indy now drives like it should.