SCCA STU build

[Amalfitano]

And yes, an LSD makes the car feel so much better. Ridiculously better! I really can't wait to get the coilovers in, test fit the star specs and get the front to feel more planted as well.

Even without the new springs, just the rear bushings, rear sway and the LSD make the rear feel so much more solid, i wouldn't even be able to put a % estimate to it. It's a different rear end through and through.

[Amalfitano]

Originally Posted by RedTRex

I am running a square setup 265/35r18 XSs on CSL reps with ASTs and Vorshlag camber plates - I slam them at the track. Hotchkis FSB (I am the original member of this forum to install one).
- 265s are a very tight fit - the rears rub on large dips/bumps.
- No mech LSD. Been successful w/o so far.

*strongly recommend you keep stock RSB as this car is prone to snap oversteer.....trust me I know I had the Hotchkis RSB on mine for a short time.

just a by the way,

http://www.1addicts.com/forums/showt...29#post9093829

Here's the post Berk had on their experience with rear sways based on different diffs, though this is specifically a torsen diff versus a clutch type diff.

[Amalfitano]

How little i'll have the time to wrench is starting to piss me off...

My brother might be finishing the fronts tomorrow, maybe the rears too. I wasn't worried about getting everything done in time for the 2nd until i remembered a wedding on saturday. That lost day made me freak out a bit, so i won't be garaging the rest this weekend, and instead i'll be getting an alignment hopefully, and seeing the true fitment of the wheels/tires and how much emergency fender rolling needs to get done before the first event.

Even with me worrying about getting things done in time, i'm pretty sure i'm swapping midpipes too. Though i have no idea if the Berk Full Race system will net me more than 100dB from 50 ft. away or not. Push comes to shove, i'll be in the sport muffler market soon.

[bradford]

I'm the audi guy with the Schroth harness.

Are you going to the Windy City event at Autobahn at the end of April?

I was running the M3 front and rear bars last year and I did have issues with inside wheel traction through the turns. I've got Ohlins DFV shocks with 400/800 Swift springs, the M3 suspension conversion (except the rear camber arms), adjustable rear toe links, and 235/275 Nitto N01s. -2.8 degrees front, -2.2 degrees rear.

Next week I have a Quaife going in and I'm hoping that will help a bit with grip, but I'm still concerned with picking up a wheel, so I'll see how it goes this season and might go back to the stock rear ARB.

Hope to see your car at the track this year some time...

[bradford]

Originally Posted by Amalfitano

I'll be putting on APEX Arc-8's, 18x9 et 42 up front with a 5mm spacer, and 18x9.5 et 62 (or is it et 63?) rear.

I'll also be staying with Toe zero up front, and going Toe-in, not sure how much yet, in the rear.

Watch your rear camber with 275s on those wheels. You should be ok with the -1.7 or so that the oem toe link allows but if you get adjustable toe links for more camber you will need a spacer to keep the inside edge of the tire from hitting the inner body tub in the wheel well. Ask me how I know...

[Amalfitano]

I'll be out of town for the windy city event at the very least. Though i think I'll be doing one of the PDX's with SCCA. I'll be primarily focusing on autocross for awhile but hope to get some track time too.

I can't do the adjustable toe link in the Solo-2 class i'm in unfortunately, so staying with the rear camber at 1.5-1.7 is my intention thus far.

So you clipped the schroth harness into a bolt on the seat that attaches the seat to the track then? I'm sorry to say i haven't looked at that part yet since i've been focusing on the rest of my upgrades.

And did you upgrade the subframe bushings?

[bradford]

Harness - yes, I removed the rear outboard seat track bolt, slid the metal harness mount point between the floor and the seat track, and reinstalled the bolt. This is the second car I've utilized this attachment method in (Mini Cooper S being the other) with good results. That being said, I've never hit the wall at 100mph in either car either, and I'm not an engineer, so I assume no liability related to such an install and I don't advocate that others do so.

Subframe bushings: Yes - absolutely necessary, 100%. It's a crapshoot where the car's going to point without them. The OEM ones are a joke - the rear axle may as well be fixed to the car with silly string.

[Amalfitano]

that plate with the mounting hole, did you bend it for fitment, or keep it straight?

[bradford]

I bent it upwards. They're designed to be bent (once) to contour to the installation application.

[Amalfitano]

How aggressive of a bend did you go with? By a quick eyeballing, i thought that 35-45 degrees should be enough.

[Amalfitano]

CLUNKS, hate 'em. I'm gonna grab some new strut top nuts, make sure everything is seated correctly and hope for the best.

[bradford]

I don't have it in front of me right now, but probably a more aggressive angle than that, maybe 60-80 degrees? You want it pointed straight up toward where the harness is coming from.

[Amalfitano]

Makes sense, i was thinking on in terms of not going too aggressive with the bend, but it can handle it just fine by the look of it.

[BimmerMeUp]

Which Schroth harness, the Rallye 4? Quick Fit?

Thanks!

[Amalfitano]

Quick fit. I think that's what Bradford did as well, from his previous Audi, but obviously he can speak for himself

[HondaGoneRogue]

Originally Posted by BimmerMeUp

Which Schroth harness, the Rallye 4? Quick Fit?

Thanks!

They do not produce a quick fit for our cars .
If you get the rallye 4 make sure it is ASM. You don't want your guts jumbled up in the unfortunate event of a front end collision.

I will get the profi II ASM for me and the rallye 4 for my passenger. (Rallye 4 isn't FIA certified.)
Rallye 4 ASM: http://www.soloracer.com/rallyecross.html
Profi II ASM: http://www.soloracer.com/schrothproffe.html

Make sure you read up on the ASM technology for those who won't go to at least a 5 point harness. (I don't want to drill the floor.)

But I have a harness bar (also VERY important) and will wrap the ends. Everyone just sandwiches the lap connections between the floor and the seat bracket?

[Amalfitano]

Right now i'm not doing race seats, and primarily autocrossing. Looking at the fit that bradford did, It's definitely doable, and i'm not sure why they didn't just release one with the intent of his way of doing it. Seems right on.

[HondaGoneRogue]

I'd love to see the setup! I haven't plunked down any cash yet.

[BimmerMeUp]

Keep in mind this is an STU (autocross cone mashing class) thread - my D Stock 135i and I don't go out on a track, and if I find the money to take it to STU, that will still be true. I just want to get my butt planted in the seat more firmly, a step above a CG Lock.

So for me, a Schroth would just go in and out at an autocross event, and wouldn't end saving me from a wall, since I don't race like that.

But thanks for the info!

[Amalfitano]

my problem with cg lock was just my own laziness. I left it on, then someone else drove my car and mangled the lever, so it's done and done now.

[bradford]

Originally Posted by Amalfitano

Right now i'm not doing race seats, and primarily autocrossing. Looking at the fit that bradford did, It's definitely doable, and i'm not sure why they didn't just release one with the intent of his way of doing it. Seems right on.

Well, from an engineering standpoint, the seat track bolts are designed to support the weight of the seat only in the event of a collision. Your body weight is restrained by the OEM seat belt, which is not affixed to the seat, but the body of the car. So by adding your body weight to the equation for that bolt, you could be exceeding the force for which it's designed. That being said, the outboard lap bolt mount point should not receive the lion's share of the load in a collision, IMHO.

Will the seat track bolt that I used for 1 of 4 mounts fail in a gnarly collision? Possibly, but I hope not.

Honestly, I think the additional control afforded by not having to worry about bracing myself for every turn vastly outweighs the potential risk in the event of a booboo. An ounce of prevention is worth a pound of cure...

And if you're just talking about autocross as opposed to the 130-140mph speeds you might see at a road course? I wouldn't lose any sleep over it...

[bradford]

And yes, btw, my harness is ASM equipped. I agree that this is important to prevent both submarining and spinal compression in a head on collision.

Also - my harness is a quick fit. The quick fit is just a Rallye 4 with OEM style attachments at 2 points so you can snap it in and out easily.