Better CUP wear...

[shimmy]

Its taken me a few years to get used to and control tyre wear on the CSL.

The obvious managing tyre pressure by not letting it get too high or low is the best starting point, then making sure you are running optimum geometry to get grip but also to shag the tyres early.

My purchase of 18 x 9.5J inch rims in 2010 was a final attempt to get better grip but also run a square set up in a wheel size where you have a choice of road legal and non legal Tyres.

In 2010 i did only 8 trackdays inc some wet ones and used a full set of 18 inch 265/35 Cups and this year i have done 3 heavy trackdays at Spa and Snetterton and this is the wear.

FRONT 3.5-4.0mm


REAR 3.0mm


Wear is pretty even although I think in principal I am more aggressive now on my car and Tyres.

Time is right to swap front and rear now and use he good edges of the rears on the front and decent rubber of the middle of the fronts to the rear:thumbs:

[The Gorilla]

Hi,

Shimmy- with your all 'square' set up what
camber and toe do you run front and rear ?
if its not a ''Shimmy Racing'' seceret please ?

Its just that your fronts appear very even for
say a 3.5 neg camber up front with 20secs or
more toe out front and in at the rear?

Just interested as I think the E46 handles
better if its an all square set up with a little
more overall track width up front.

Regards,

The Gorilla.

[AlexGTT]

That's awesome tyre wear Shim. Have to report much the same on my current square set-up. I've had similar wear from one set that was already part worn and have done one Ring trip, one Spa TD, one Donny TD and one Snett TD plus all road miles inbetween.

I don't produce the laps times Shim does and I'm on 19" std all round but geo's and tyre management approach is similar.

[shane@mbtech]

Hi,

Shimmy- with your all 'square' set up what
camber and toe do you run front and rear ?
if its not a ''Shimmy Racing'' seceret please ?

Its just that your fronts appear very even for
say a 3.5 neg camber up front with 20secs or
more toe out front and in at the rear?

Just interested as I think the E46 handles
better if its an all square set up with a little
more overall track width up front.

Regards,

The Gorilla.

I ran square set up, same as shims. And my tyre wear was perfectly even like his.
-3.5* camber. Approx 15-20 secs out front toe.
-2.5 ish rear camber 15 secs in toe

Hammered on track and for long periods too, perfect even wear front and rear and yes the wider track front does make a difference, front end grip drastically improved.

I wasn't running cups though, I was on a048,s.

[northernjim]

what caster do you have on the front of these cars by the way?

I ran square set up, same as shims. And my tyre wear was perfectly even like his.
-3.5* camber. Approx 15-20 secs out front toe.
-2.5 ish rear camber 15 secs in toe

Hammered on track and for long periods too, perfect even wear front and rear and yes the wider track front does make a difference, front end grip drastically improved.
.

so driving sideways gives you even wear does it:smokin::beer:

[shane@mbtech]

what caster do you have on the front of these cars by the way?




so driving sideways gives you even wear does it:smokin::beer:

Exhibition laps don't count:smokin:

But yes even after they oulton park session tyre wear was still perfect

[magnust]

Front camber 3,2 with swapped left-right top mounts doesn't work well with stock max 1,5 camber in the back. I know after a (fun and quite a bit sideways) 240 km track day last Sunday on Mantorp Park. Need more camber in the back before next track day...

[shimmy]

My current set up is -2.75 front camber, 1mm toe out front, and -1.25 rear camber,

It mainly was set like this as I wanted to run road at less than -2.00 to avoid tyre wear on the inside.. Looking at my tyre wear I guess. Could run more front camber on road and track. I will try -3.25 front and maybe -1.50 rear although pyro tests at Snett showed that at -1.25 rear camber I was getting perfect spread of hrs temps so this is probably fine as it is.

At the end of the day I don't think you should worry to much about max corner road holding by maxing camber as it just gets your Tyres unevenly temps across the tread and then will be loosing you grip, not gaining it. They aren't slicks!

[Rutkowski]

What's aquaplaning like with a square set up, shimmy?

Thanks for the info on tyres. :thumbs:

[shimmy]

What's aquaplaning like with a square set up, shimmy?

Thanks for the info on tyres. :thumbs:

Depends on your geo, not the square set up. I knock my camber back to -1.75 for road and wet track.

If the camber is not too great on the road braking is improved in the dry and not noticeably any worse in the wet

[azrael]

I thought this would be a thread about cricket

[chief]

I ran square set up, same as shims. And my tyre wear was perfectly even like his.
-3.5* camber. Approx 15-20 secs out front toe.
-2.5 ish rear camber 15 secs in toe

Hammered on track and for long periods too, perfect even wear front and rear and yes the wider track front does make a difference, front end grip drastically improved.

I wasn't running cups though, I was on a048,s.

Hi,

Here in Cyprus as far as I know the measuring units for toe are like the following:

0.05" per side,
1.2 mm per side,
0.10° per side,
0°6' per side (that reads 0 degrees, 6 minutes)

The most commonly used in alignment garages here is mm.
Can someone explain what “secs” is as per the earlier post, or at least tell me how to convert it to mm?

Thank you

[O'Neill]

Hi,

Here in Cyprus as far as I know the measuring units for toe are like the following:

0.05" per side,
1.2 mm per side,
0.10° per side,
0°6' per side (that reads 0 degrees, 6 minutes)

The most commonly used in alignment garages here is mm.
Can someone explain what “secs” is as per the earlier post, or at least tell me how to convert it to mm?

Thank you

1mm on a 19" wheel equates roughly to 8 minutes. Sorry 6.5 mins

Seconds, they probably mean minutes, as 60 mins in a degree and 60 secs in a min, an un-noticable amount of adjustment.

Conversions below.

http://members.roadfly.com/kef/Camber_Toe_Math.pdf

[chief]

I believe they probably means mm.
3mm (1/8") toe out, sounds good adjustment for -3.5 camber.

3 mins in a degree, is about 0.5mm. This is not right toe out adjustment for track.

[billyboysm3]

So in theory swapping the fronts with the rears after each TD would also maintain maximum & even tyre tread on all 4 corners at once, if geo is correct.