S2 Avant Hillclimb/Track suspension settings

[raymor]

Well this year, due to life getting in the way, I've had to result to using the S2 Avant for my hillcliming debut - it should have been the Imp, but the tack has changed on that and increased by 4 cylinders too, so it's delayed. Anyway that's by the by and what I really need is suspension settings for a good handling Avant.

My debut should have been this weekend at Doune hillclimb, but it was not to be...

Currently the spec is:

H&R springs front and rear.
Koni Adjustables all round... option to have the front bilsteins rebuilt (off car at the mo)
Neuspeeed adjustable rear ARB
Hillclimb tyres are Toyo R888 225/45 x 16 - Lowers gearing and center of gravity at same time.
RS2 ARB and poly bushes on the front.

... also I've got a sample rear subframe bush from Ben (S2Avant) and I'll turn some up when I remember to get the bar from the metal shop -

I'm thinking -1.5 to 2.0 camber on front and -1 camber on rear and as much front castor as I can muster on the standard bottom balljoints

I've got cornerweight scales and I'm going to be weighing the beast and doing the suspension set up myself with a camber/castor gauge ... so I'll be posting some specific corner weights of the beast soon. With and without seats and spare etc.

So... if you've been successfully tracking or competing your Avant with 380/400 ish bhp - then please let me know. Remember - hillclimbing tyres ain't hot, so I guess settings that work when coldish would be good

Either that or this will be a voyage of discovery through 2008

thanks,
Raymond

[Rusty]

Be good to hear how you get on, I'm sure it'll suprise a few people, just make sure you don't have any boost leaks or you'll be a bit embarassed when the overboost protection cuts in...

Castor adjusting front subframe bushes would help you get more than the balljoints would allow, I assume this is what you are referring to wrt S2Avant?

Not sure about the RS2 front ARB, a standard S2 should give you more grip as it's softer, might be worth trying them back to back or even disconnecting the FARB alltogether and reporting back. Also, you might be able to attach the standard rear bar (jubilee clips? ) to the neuspeed one to really stiffen things up, not sure on space on a Avant having never worked on the rear suspension of one.

Good luck, make sure you get some pices

[raymor]

... I've done most of the engine work already and once I've got rid of the niggles, I don't anticipate any boost related headbanging problems

The bushes are the rear subframe ally bushes that Ben had done eons ago and I managed to get one as a template, so it'll take a little of the slop out the rear end without too much added harshness.

It would be ideal to be extend the front ARB mounting points to be able to soften it up and give a few settings. I'll to have a look at that and see if I can make something up

The Neuspeed ARB is already 19mm and coupled with the torsen rear diff should make it responsive enough... there's very little leeway between the Armco at Doune, so it can't be tail happy

As a starting point it would be good to have some settings that are proven... come on Avant owners, it can't all be just drag racing

[Rusty]

There are 22.5mm 24mm and 25mm versions of the FARBs that will fit your S2. Any B4 or facelift typ89 coupe should have something that will fit or get one new for about £80 each.

Front bushes that allow for castor increase are available.

Super stiff RARB on the front heavy S2 is fine unless you're off the power and too fast, I'm running 25mm rear and 26 front and it's very controllable but the best thing is that it gets rid of the power-understeer that can happen.

Have you fitted the V8 internals at the rear then?

R888s will keep everything in check

[raymor]

Yeah, the V8 diffs been in there for a bit now... cheers for the info on the ARBs

[raymor]

What camber are you running at the front Andy?

[Rusty]

I'm on stock settings as it's a road car first and a track toy second. I'm sure it would handle better if I put some thought into the settings but it's a matter of finding a decent motorsport place nearby who'll do it for you.

What do you think to the torsen in the boot? There have been mixed reports on here.

[raymor]

The torsen provides a more neutral feel and less understeer... time will tell if it'll take real abuse, but I'm fairly confident that it won't pose a problem with the power I'm running.

I'll be doing my own chassis set up, I just need to get/make a set of basic turn plates so I can adjust the camber etc. without having to re-settle the car over and over again. It'll be another learning curve, but it'll be a good one

Will need to get the remaining niggles sorted out and get it set up before the 10th of May. I wasn't planning to head Aberdeen to do the Fintray hillclimb, but because I've missed Doune I'll need to fit in the extra rounds,so should start to gather some data on weight, camber etc soon.

[maRS2]

I'm not doing hill climb race but a lot of up mountain road here in the french alp's early morning when empty roads to go ski.

I have -1,3° camber front ( max I can put with my setting) and -1° rear

My RS2 also have:
Neespeed bar
poly bushes
aloy subframe
bilstein/ original spring
V8 rear torsen

one of the best upgrade i did was to get wider tyre front. I got 245/35x18 front and 225/40x18 back all Michelin PS2
I like the RS2 a lot like that but still dream of the handling of my old Scooby so much lighter, fun and forgiving.

[maRS2]

What turbo are you using for hillclimbing?

[Lloyd]

I'm not doing hill climb race but a lot of up mountain road here in the french alp's early morning when empty roads to go ski.

I have -1,3° camber front ( max I can put with my setting) and -1° rear

My RS2 also have:
Neespeed bar
poly bushes
aloy subframe
bilstein/ original spring
V8 rear torsen

one of the best upgrade i did was to get wider tyre front. I got 245/35x18 front and 225/40x18 back all Michelin PS2
I like the RS2 a lot like that but still dream of the handling of my old Scooby so much lighter, fun and forgiving.

Sounds like a nice setup. I was wondering about your choice of tyres though
If you have essentially different rolling radius wheel pairs, front to back, are you not going to be overworking the center torsen diff? I mean, the final gearing on the front wheels is not the same as the rear wheels any more.

Does this matter at all?

[maRS2]

The Torsen can accept up to 10% difference.

This set up is only 1,3% difference.

You can check it their dailing the nu!mber's in
http://www.miata.net/garage/tirecalc.html

or their i the rev/mile column.
http://www.tirerack.com/tires/Spec.j...irePageLocQty=

[maRS2]

Your 4 wheel are anyway never at same speed because of curve's but also bump tire that get faster worn than over that's why their is diff.
I've been driving with this setup for over 40000km with no problem.

[Lloyd]

interesting.... I guess then that this ultimately 'forces' a change to the front/back torque split, transferring more grunt to the rear wheels...? is this kinda correct?

[maRS2]

NO it's just that with our super heavy front end car (over 1T on frontaxle) we need much more grip in the front than back and like that you get a better balance.

I didn't event anything this was the setup of the MTM RSR audi coupé.