Rear rims on front....?

[PeteLawton]

Hi, after a recent visit to the Ring and Spa I noticed a few CSL's running rear wheels up front...
Anyone done this on here, any adverse effects? any advantages besides the looks....

Thanks.

[houlbt]

On track it's superior of this I am sure. However this won't fit without modified suspension/topmounts running an aggressive camber setup which. This will result in increased tyre wear on inside edges if you do lots of road miles and the car will tramline a little more on Britains crappy roads.

Ultimately though I love it..... but you do need to make sure the car is setup right when this work is done.

[houlbt]

Gratuitous image posting sorry.....

[RatBoy M3CS]

I'm looking at this to get the last bit of understeer out of the front end now on my CS.. I have KW3's on it, and running 8.5J fronts at present, these just clear the strut and spring by 2mm, and with my 10mm soacers on it to clear the AP's i'm at the edge of the outer arch clearance as well, so it looks like a 60mm parralel spring is going on next to free up some clearance..but even then its going to be close for clearance all round, specially with any lock on..

Anyone got any info, or exp on how this feels on the track..?

[m12_nathan]

You don't need spacers to clear APs with proper CSL fronts, only the CS rims.

However the KW3 tuv states you need spacers for them anyway.

[RatBoy M3CS]

Correct... you dont need spacers if you run the CSL fronts, as they already have the offset to clear the calipers..

But..the extra 10mm offset I have found feels much better..

I've just checked my rim / strut clearances, and its the spring platform and coil thats the problem, next job is a 60mm core race and helper spring and this should give me some more clearance..

[houlbt]

Well running intrax you don't need a spacer to run rears on the front. But you will need to run aggressive camber

[RatBoy M3CS]

I'm trying this today, and will report back, but on first glance under the arch, the inner edge of my 8.5J rim is just clearing the bottom spring platform by 2mm, so i cant see how i can get any more wheel inboard..? my CS seems to be running a similar ride height to your lovely CSL..

Do intrax run a smaller diameter spring and platform..? or std 60mm core..?
What front camber are you running to get the outboard clearance too..?
I'm going to pull mine over to nearer 2 degrees and see how much extra clearance that frees up..
What front camber have you found works best for track use..?

Rodger

[m12_nathan]

RatBoy M3CS said:

I'm trying this today, and will report back, but on first glance under the arch, the inner edge of my 8.5J rim is just clearing the bottom spring platform by 2mm, so i cant see how i can get any more wheel inboard..? my CS seems to be running a similar ride height to your lovely CSL..

Do intrax run a smaller diameter spring and platform..? or std 60mm core..?
What front camber are you running to get the outboard clearance too..?
I'm going to pull mine over to nearer 2 degrees and see how much extra clearance that frees up..
What front camber have you found works best for track use..?

Rodger

Pretty sure that 2 degrees won't get you close. More like 3-3.5 required.

[houlbt]

Yes... woudl need to check but if I recall correctly my car is something like -3.5 on the front and -2.0 on the back.

[RatBoy M3CS]

I'm checking with KW to see what their top mounts max out at on negative camber, -3.5 is achievable so i'm told..

Houlbt.. where are your spring platforms relative to the inside edge of your rims..? highter or lower..? im struggling to see how i can get any more inboard clearance.. clearly it can be done but are your rears a standard offset or shimmed out..?
I've just trigged it out and -1.25 to -3.5 gives me another ..24mm ish outboard clearance..almost the inch i need.. never has an inch been so important...!

Hows this on the track...? the KW guys tell me that ideally the front should camber about 30' more than the rear..?
Does this take out every bit of the understeer..? and bias the car to oversteer much or is it neutral..?

Rodger

[m12_nathan]

From what I've read it makes it an absolute pig on the road.

Email phatGixxer from here - he ran rears on the front with KW3s.

[houlbt]

m12_nathan said:

From what I've read it makes it an absolute pig on the road.

As stated further up this thread... it will tramline more yes, but it's far from being terrible.

[RatBoy M3CS]

Well.. the rears on front trial went well...!

8/9mm clearance inboard between the rim and spring platform.. so i will machine 6mm off the wheel mounting face, then see what negative i need to dial in to get clearance..and it should work ..! hopefully nearer 2 deg 30'..

Without machining the rear wheel mounting face i would say i need every bit of the 3 deg 30' quoted above to get some clearance under the outer arch lip ...;)

Didnt get a chance to try it lock to lock with the bare rims on to see what fouls here.. any one had any problems, or had to adjust any lock limits..?