Increasing front end grip.

Post Mon Apr 13, 2015 10:32 am

Hey guys,

I have been struggling to maintain front end grip in long sweepers and also in variable radius bends where they start smooth and tighten up before the exit.

The main problem seems to be understeer where I can't get the power down without drifting off course. I have tried playing with f/r tyre pressures, taking different lines and also slower entries but I am still losing time in these segments due to a lack of front end grip.

Any ideas?

Post Mon Apr 13, 2015 1:50 pm

What toe and camber do you have on the front?

Post Mon Apr 13, 2015 3:06 pm

-2 degree toe in on the front, standard camber except for the eccentric control arm bushings.

Rears are totally standard with E46 top mounts.

Bilstien B6 all round with Stiffer springs.
Standard 318is ARB set up and braking system.

All of the bushes and bearings are new original BMW items

Post Mon Apr 13, 2015 3:55 pm

It was a long time ago that I set my car up but I think I had 0 toe or maybe 0.5 toe out to help with turn in. Check the m3 settings, mine handles brilliantly but with a tendency to oversteer mid to corner exit.

Post Mon Apr 13, 2015 3:56 pm

When I get my alignment rechecked I'll post up what I had it set to

Post Mon Apr 13, 2015 6:41 pm

try unbolting front arb? do you know your spring rates ?

Post Mon Apr 13, 2015 7:43 pm

Your wheels are pointing the wrong way, you want toe out for cornering
With standard camber you will only be using about 50% of the tyre tread

Post Mon Apr 13, 2015 7:44 pm

Not sure about spring rates. They are gmax 30mm lowering springs. I will unbolt the front arb. Thinking about it there is probably 30mm of pre-load on there trying to push my inside wheel down when cornering.

I will also toe out the fronts. How much toe out would be recommended?

Post Tue Apr 14, 2015 11:19 am

You need some 'toe out' and you could also try increasing your castor as this will aid your dynamic camber.

Post Tue Apr 14, 2015 11:25 am

Start at about 0.5mm and see how you go

Dont unbolt your ARB

Post Tue Apr 14, 2015 11:44 am

DanThe wrote:Dont unbolt your ARB

Would tend to agree with this

Post Tue Apr 14, 2015 12:45 pm

Do you know where I can get shorter drop links? The arb appears to be loaded up due to lowering the car and it does not sit parallel. It looks like it is pushing down on the control arm and my mondeo drop links dont have much slack left for free movement. ( it is at an angle and the rubber boot is fully compressed on one side of the droplink)

Post Wed Apr 15, 2015 8:39 pm

OK, small update, I checked my tracking today using the string method and I am 0 degrees at the front pointing straight ahead. The rears are about 3mm toe in, is this normal?

I have sorted the pre-load on the ARB. Just loosened the bushes, oiled and tightened the bars are nor sitting parallel again. Still understeering though.

When I get time I will try toeing the fonts out a bit and see how that goes.
The rears are not adjustable but are they meant to be toe in?

Post Fri Apr 17, 2015 1:24 am

Using the string method, did you correctly account for the difference in width between the front and rear? If I remember correctly it's about 12mm.
I don't think there should be any deviation from straight ahead on the rear.

Post Fri Apr 17, 2015 10:06 am

The rear will always be toe in, even more so if you lower the car, 3mm is not huge, but even so the rear alignment will not make the front understeer