Handling on track

[fasteddie84]

Hi all

I have just returned from a track day at Fay De Bretagne in Nantes and I have mixed opinions on the handling.

Before I go on, my car is as follows:

2002 E46 M3 manual
BC Racing BR coilers
H&R front and rear anti-roll bars
OEM 18’s square setup
Michelin 25/64/18 hard compound slicks

I had the geo set to the following after I fitted the suspension and let it settle.

Front camber = -2 degrees and 36 minutes
Front caster = 5 degrees and 25 minutes
Front toe = 0

Rear camber = 2 degrees and 15 minutes
Rear toe = 0 degrees and 3 minutes

Having done a wet track day at Loheac at the end of March, I decided to add more caster and maxed it out on the top mounts.

After the morning runs at Nantes, I noticed that there was a lot of pick-up on the inside edges of the front tyres and some on the middle of the rears. The rear tyre pressures were 30psi hot but I upped them to about 32psi to sort out the wear and they seemed to be fine for the rest of the day.

With the fronts, I added more camber (not sure what to but it was the 2nd from max setting on the top mounts) and took it out. I then let my mate drive it for about 12 laps and when he came back, the fronts were perfectly worn but said that the front understeered a bit. He and another mate added 5 clicks of hardness to the front dampers to sort it out and changed the front ant-roll bar from medium to stiff. I took the car out and it was better but it didn’t feel right so came in and checked the tyres and there was pick-up on the inside edges.

I am a bit lost as to what to do. Should I put the ARB back to medium? Should I add more camber? Is my mates drive style better that mine hence the difference on the tyre condition after a session?

Any help would be much appreciated.

Edward

[shimmy]

No idea but camber with slicks should be. 3.5-4.5 degrees, that's one of the troubles with running slicks on a road car.

[alexk]

5 degrees caster?

Why people remove caster on a csl?
Its no good :banghead:

[fasteddie84]

Simple answer to this, I live in Jersey so we only have a couple of places who can do 4 wheel alingment. The garage I took it too, I told them I wanted max caster and that's what they gave me. They obviously didn't have much of a clue as they didn't make any adjustments using the fully adjustable top mounts and they butchered the mounts using a pry-bar. Cowboys!

This is why I am trying to set the car up myself using the top mounts and then take it to them and ask them to check what the settings are and then discuss with me about what to do. I will probably ask them to ensure that both sides are even and nothing more than that.

Hopefully it's running more like 7 degress if not more.

Oh, it's just a standard M3. I feel the people on here track their cars more on here than the M3cutters and that I would get a more helpful response. Don't prove me wrong

[fasteddie84]

I am tempted to put max camber on as I read somewhere on here that Thorney reckon 4 degrees is best for slicks. I did reset the front dampening as I think it was something like 16 out of 32. I put it to 10 and it still understeered but thinking about putting it up to 12 and putting the ARB to medium. I was also thinking about softening the back by 1 click (not sure what it's on) to improve traction coming out of the bends.

Any comments?

[shimmy]

I am tempted to put max camber on as I read somewhere on here that Thorney reckon 4 degrees is best for slicks. I did reset the front dampening as I think it was something like 16 out of 32. I put it to 10 and it still understeered but thinking about putting it up to 12 and putting the ARB to medium. I was also thinking about softening the back by 1 click (not sure what it's on) to improve traction coming out of the bends.

Any comments?

Can't go far wrong if you listen to Thorney.

[fasteddie84]

There's just something in the back of my mind that it's my driving style.

My mate is a very good driver (go-karting champion) and when he drove it, the tyres came back looking almost perfect. We changed the ARB from medium to hard and added 5 clicks of hardness to the front and when I came back, there was pickup on the inside edge.

The last corner after the long straight, I was taking at about 80 to 85 whereas he was taking it at about 90 so maybe he is pushing it more and making the car work more. I would have thought that it would make a bad setup show worse if you pushed it more.

When turning, the front felt like it was juddering as if it was breaking traction and almost skipping around the corner.

I would have put the setting back to how they were but I ran out of time.

I don't have enough experience to judge and by the end of the day, was getting annoyed.

[uncle benz]

It's a very difficult thing to judge without being there, but it sounds like you have some basics wrong. If the car understeers too much, soften the front dampers and stiffen the rear. If you have too much oversteer stiffen the front and soften the rear. Definitely move the front anti roll bar back to medium. Perhaps even try the softest setting.
Slicks can also be difficult to get pressures right on too. Plenty of negative front camber is needed. Ideally 4 degrees, and start off with the tyres quite soft - 24psi is where I start. You'll struggle to get the heat in them if you go out with too high pressure.

[Mike RT4]

There's just something in the back of my mind that it's my driving style.

My mate is a very good driver (go-karting champion) and when he drove it, the tyres came back looking almost perfect. We changed the ARB from medium to hard and added 5 clicks of hardness to the front and when I came back, there was pickup on the inside edge.

The last corner after the long straight, I was taking at about 80 to 85 whereas he was taking it at about 90 so maybe he is pushing it more and making the car work more. I would have thought that it would make a bad setup show worse if you pushed it more.

When turning, the front felt like it was juddering as if it was breaking traction and almost skipping around the corner.

I would have put the setting back to how they were but I ran out of time.

I don't have enough experience to judge and by the end of the day, was getting annoyed.

If he is a karting champion and is having no problem making the car work, why not get him to set the car up and then give you some tuition on how to get the best from the car? It sounds more like your driving style than a problem with the car if he is able to drive it that fast and have no issues with the tyres?

[shane@mbtech]

I'll apologise for being blunt

BC coilovers are cheap shit,

[shimmy]

I'll apologise for being blunt

BC coilovers are cheap shit,

Apology accepted :whistle:

[fasteddie84]

I'll apologise for being blunt

BC coilovers are cheap shit,

No need to apologies mate. If I had unlimited funds then they wouldn't be my first choice but I run to a budget. If I went for something better and twice the cost then I couldn't afford other things.

Will look at adding more camber for the next track (Fontenay Le Comte) next month and tweak the dampening settings. Thinking about keeping the ARB on hard and putting the rear on hard too.

I also need to setup my front shocks properly as I think the preload is out.

My mate isn't coming to the next one but he will be coming to Le Mans (Maison Blanche and Bugatti circuits) in August so will see if he can take me out then and show me where I am going wrong.

He drives a 2004 Civic Type R which has been setup so well, he keeps up with the M3's and GT3's unless there is a straight that is more than 120mph. This is partly the car and partly his skill.

[fasteddie84]

We start Tyres at 22psi, and about 26psi hot, front camber at least -4 and rear -3.5.

Change those two things before your next track day and let us know how you get on.

Also rotate the front and the rears after each day.

I had 30psi and -2.25 camber on the rears and they were wearing ok but upped the psi to around 32/33 and they were wearing perfectly.

Maybe the more camber you put in, the less pressure you need in the tyres?

Yeah, going to rotate them this time.

[shimmy]

I had 30psi and -2.25 camber on the rears and they were wearing ok but upped the psi to around 32/33 and they were wearing perfectly.

Maybe the more camber you put in, the less pressure you need in the tyres?

Yeah, going to rotate them this time.

Unless you are running high camber chances are you are just not working e tyres evenly or near their potential. They may be a cheap options ith Worn slicks but not necessarily a good option.

Only way of telling is by getting pyro readings on re temps across the front and rear tyres.