I too want to reduce the understeer of the M. Beedub suggested a camber shim kit which is basically longer bottom shock bolts with washers to space the shock out creating more camber. I have wondered about the camber pins myself and after seeing them I don't think there's much adjustment but I'd like to hear other opinions on the subject.
alignment query
- Thread starter mad4slalom
- Start date
Sim_Simma said:
I'd go with rip off on this too. Forcing someone to have a complete set of jobs done, not just the element of it you want/require
No different to a bank granting a loan and telling you that you can only have it with PPI and we all know where that ended up
exdos said:
negative camber will also have an effect, as the tyre starts to roll and uses the outside edge, using negative camber brings this back under eand once the tyre has rolled is using more of the tread, hence why we see heavy shoulder wear during track conditions.
Beedub said:
Describing handling effects in text is difficult. As you say, negative camber obviously does have an effect on steering but it's largely used to counteract lateral bodyroll during cornering to keep the widest contact patch on the outer tyres when bodyroll occurs, which is far more important on track than on the road. However, toe angles tend to affect the willingness of the car to turn (or not) more than camber. All cars have toe adjustability on the front wheels (i.e track rod ends), but unless you have camber plates, then camber isn't as easy to adjust. If anyone wants to get rid of understeer they should try toe out to see how it works, but mind that ditch!
I had some coil overs fitted years ago on my old golf and the guy doing it reckoned he could successfully eyeball the toe!
Needless to say it was a fucking hopeless effort and whilst i dont remember exactly what the numbers were, you could actually see it was toeing out by several degrees!
I've never known a car to feel so alive, it was genuinely exciting to drive but you had to be very smooth and careful on corner entry!
Needless to say it was a fucking hopeless effort and whilst i dont remember exactly what the numbers were, you could actually see it was toeing out by several degrees!
I've never known a car to feel so alive, it was genuinely exciting to drive but you had to be very smooth and careful on corner entry!exdos said:Beedub said:
Describing handling effects in text is difficult. As you say, negative camber obviously does have an effect on steering but it's largely used to counteract lateral bodyroll during cornering to keep the widest contact patch on the outer tyres when bodyroll occurs, which is far more important on track than on the road. However, toe angles tend to affect the willingness of the car to turn (or not) more than camber. All cars have toe adjustability on the front wheels (i.e track rod ends), but unless you have camber plates, then camber isn't as easy to adjust. If anyone wants to get rid of understeer they should try toe out to see how it works, but mind that ditch!
You guys both know a lot more than me on the subject. In my minds eye Beedubs theory makes more sense to me, added negative camber should even out the contact patch as the car rolls in the corner. How would toe out actually reduce understeer? I'm not questioning your knowledge and experience, merely trying to understand it
Sim_Simma said:You guys both know a lot more than me on the subject. In my minds er should even out the contact patch as the car rolls in the corner. How would toe out actually reduce understeer? I'm not questioning your knowledge and experience, merely trying to understand it
Why do cars have any adjustment for toe angle at all? So why do manufacturers tend to set the front (steering) wheels with toe in rather than with zero toe (i.e. wheels parallel to each other), or toe out? The reason why they use toe in is so that both front wheels are heading towards the same point some distance in front of the car, so that the car has a tendency to self-steer straight ahead, which makes it so much easier for all the incompetent drivers that get to drive cars to keep them on the road. It is acknowledged that a car with inherent understeer is much safer for Joe Public to drive than a car with neutral handling or one with oversteer. A car with toe out has both front wheels pointing away from each other, so both of them are permanently wanting to go in opposite directions, but once the steering is turned, say, to the left, then they are both pointing in the same way as the inside wheel, so the car tends to dart in that direction, which tends to rotate the car faster and hence create oversteer.
The reason that cars are set with negative camber is so that when the car makes a turn, the increased loading onto the outer wheel, due to lateral bodyroll, will result in the contact patch being across the full width of the tyre, as the tyre becomes vertical, with no camber under roll.
If you think about it: it's the turning of the direction of the front wheelsl which initiates a turn and that is made easier or more difficult, by the toe angle, as explained, and once the car has begun to turn, it will then begin to laterally roll, and that's when egative camber ensures that the wheels can take the loading on the largest contact patch for best grip.
Manufacturers set up their cars for stability, and it's interesting to see how manufacturers use more negative camber on the rear wheels for this reason:the Z4M included. Look at the Smart and Mercedes A Class, to see how much negative camber they use for this purpose on a short wheelbase car with a high CoG, coupled with toe in, to prevent oversteer.
If you can, try changing toe and camber seperately on your car, and you'll see for yourself precisely how this all works in practice.
On a side note: a lot of owners think that increasing negative camber is the best way to increase turn-in. They'd do far better to increase caster, because this increases dynamic negative camber, the only time you really need any camber at all.
mad4slalom
Senior member
I have my new front pss's now ready for fitting and alignment. i have gone 235 45 18 front and 265 40 18 rear, the stock alignment figures i found are front camber 1.00(neg) front toe 0
degree 10' and rear camber 1.50 (neg), rear toe 0 deg, 28'
i found a fast rd alignment achieved by pulling pins front camber-1.45 front toe 0 deg 4' rear camber - 1.50 rear toe 0deg 4' (toe is total, so half those figures each side )
any thoughts i want a bit more lively feel but not snap oversteer. is this amount of toe in sufficient ? having it done next week so really keen to hear thoughts as to whether it is still safe. thanks
degree 10' and rear camber 1.50 (neg), rear toe 0 deg, 28'
i found a fast rd alignment achieved by pulling pins front camber-1.45 front toe 0 deg 4' rear camber - 1.50 rear toe 0deg 4' (toe is total, so half those figures each side )
any thoughts i want a bit more lively feel but not snap oversteer. is this amount of toe in sufficient ? having it done next week so really keen to hear thoughts as to whether it is still safe. thanks
