Bump steer/ toe change

[Lee]

Right, i finally got to build the BJ4 WE this weekend, very nice too!

I built it as the manual recommended and i noticed that when the front suspension is compressed i get masses of toe in and when lifted toe out. Is this a trait of the car or off roaders in general, i cant remember after 10+ years on road.

Also is there anything i can do to stop it? i imagine it will make the car very lively under accelleration as it is.

thanks

[jimmy]

Doesn't sound right to me fella, are you sure you have things as they should be ? can you upload a piccie ?

[Lee]

Im away at work at the moment and not back till friday, ill have another look at the instructions all i can think that would alter it would be washers under the ball joints or pick up points

[university_dave]

Where are you running the upper links at the front, inner or outer hole (on the top deck)? I've got my car on the bench being stripped down at the moment, and on the inner hole there is no bump steer. However, if I moved it into the outer hole then I should imagine that, as this will give you more camber gain when the suspension is compressed, this will give you more bump steer.

[Lee]

they are on the outer hole at the moment, i assume this will have to be changed for the weekend.

cheers

[university_dave]

To be honest I couldn't tell you which is better as I've only run my car the once, and that was with the links in the inner position.

If they were in the outer then this would give you more camber gain as the suspension is compressed; i.e. the more the suspension is compressed the more camber the wheel has. It will also raise the front roll-centre. No idea quite how this affects the handling as I've not had any real experience with this car. If I did this with my X1-CR then I would expect the car to 'hang on' better through the corners, as with the increased camber gain as the tyre loads up through the corner the grip it generates should remain roughly the same with the increased camber. With the roll centre change, I would expect to see a slight loss of off-power steering going into a corner, but a slight increase in the mid and exit grip the front end generates.

I would try it with both and see what difference the change makes and which you prefer.

[Andy Moore]

Double check that you have the correct number of washers in the right places. I just took a look at my car and the only place I see where that might result from could be the number washers under the ballstuds on the steering rack. Pics would definately help, when you get a chance.

[Richard Lowe]

I rekon Andy's right, it sounds to me like you've left the 3 washers that go under the ballstud on the steering rack out.

Regarding the camber link position I always run it on the outer hole on the topdeck (short link). With the WE there's less weight biased to the front so you have to run the suspention slightly softer on the front. If you use the long link I've found there isn't enough roll stiffness and the front end colapses in corners making the car hook suddenly. I'd be tempted to try the longer link on a low grip surface if I needed more steering but not on grass/astro ect.

[Lee]

Thanks for the info everyone, i will have a look when i get home on friday, ill be racing it on sunday at teeside because i will need lots of practice

[Lee]

just to put peoples mind at rest, if you put the caster blocks on the wrong side it gives massive toe change when the suspension is compressed:eek:

schoolboy error

[Andy Moore]

Originally Posted by Lee

just to put peoples mind at rest, if you put the caster blocks on the wrong side it gives massive toe change when the suspension is compressed:eek:

schoolboy error

at least you were able to figure it out, I'll make a note of that for future reference.