SCCA STU build

[Amalfitano]

Hopefully will have some new pics today, i'll be trying a makeshift hockey puck attachment for the jack points but might just go ahead and mangle them / replace them, and get the $20 BMS solution for the jack point adapters. I have rub, but it could be solved by either or (possibly and) the touch more camber i could achieve on the passenger side (or at least looks like i can since i got it on the driver's side) and a little more ride height. I'm hoping my brother was just rushing and being stupid when he thought that we set the max ride height for where it's at. The tires on practically on the fenders. It'll probably do fine in autocross applications with a light roll as is, but street dips are the enemy right now. Yesterday had horrible lighting so the pics seemed useless...

[Amalfitano]

new shoes



closeup of the front, got the ride height better situated now. Though i still need to check if i'm shaving rubber on the driver's side again. It looks like it was coming from hard rights and the outside edge, but maybe not. Though the collar is higher now if that was the issue...



The hockey puck brace for the jack stands wasn't quite perfect, they compress pretty good. I'll probably just buy the BMS adapter. Though i'm getting some clicks towards full lock, might need to make sure the brackets for the brake lines are going through the full range of motion without interfering with things....

almost sorted

[HondaGoneRogue]

Lookin good!

[bradford]

Originally Posted by Amalfitano

Though i'm getting some clicks towards full lock, might need to make sure the brackets for the brake lines are going through the full range of motion without interfering with things....

almost sorted

Check to make sure your tires aren't shredding your oil cooler grill inside the wheel well. That could be the "clicking" near full lock.

[larryn]

Originally Posted by bradford

Check to make sure your tires aren't shredding your oil cooler grill inside the wheel well. That could be the "clicking" near full lock.

My added camber puts the upper front end link mount precariously close to the black plastic junction box for the ABS pulsers. This might be another place to keep an eye out for. (Great thread btw!)

[GaryS]

Originally Posted by bradford

- 03-24-2011, 12:35 AM

I was running the M3 front and rear bars last year and I did have issues with inside wheel traction through the turns...

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.

Ah, it appears that we do have a consensus.

[Amalfitano]

Originally Posted by larryn

My added camber puts the upper front end link mount precariously close to the black plastic junction box for the ABS pulsers. This might be another place to keep an eye out for. (Great thread btw!)

It definitely was on the driver's side at the lower ride height. I was able to see the top of that box ground down a little bit. I turned the bracket slightly to effectively raise everything ever so slightly, but i now raised the ride height, so maybe i need to spin that bracket to the lower end of the spectrum now...

Did you have enough motion range to eliminate the interference, or is a little bracket bending in my future?

[Amalfitano]

i went with rotating the bracket til tight on the endlink. I'm pretty sure i have no shot of scraping the abs wiring holder dude. i gave a little clearance between the bracket and the end link, though i'm pretty sure the geometry moves the same type of way when the car loads.

Road test showed no noises in general range at some speed. At a rest it groans pretty good about turning more than 90 degrees, but at a little speed it doesn't peep, or at least is quiet enough i'm not catching. Definitely not getting the sound i was before, so i have that to rest my hat on. We'll see soon enough! So long as i can slalom without running into anything i feel fine. I'll check my end link to see if it rubs up a bit in actual motion. My hope is to have the willpower to hold back, do my runs at about 90% to sort out how the car reacts and how i like the dampers. Especially since i'm not corner balanced or fine tuned aligned, i don't really need to push the full limits since that limit WILL be different next week.

[Amalfitano]

Yikes! Failed exercise in rear end control Spun three times in 2 runs. I'm not about to assume it was all car, everything about the dynamics were different. I wasn't attacking turns as fast in as i could or as hard through them, never encountered understeer, then when experimenting with the LSD and getting on the power earlier than before, it feels good, then i give it a little more and get a bit squirrelly. It was a cold day, so that's a factor, and i did not do any better than eyeballing my alignment and quick string testing. I thought my toe was neutral in the rear, it very well could've been even a bit toe out which would at least partially excuse me

It was only 5 runs so i didn't have all that much time to TRY to dial in, i probably could've adapted better even today and dropped a second and a half, but i was 4 seconds off from feeling satisfied. I'm hoping I stop driving like poop, and the corner balance and alignment get the car ready for me to take advantage.

No midpipes yet, no downpipes yet, no offset control arms yet, and I might grab poly for the tension arm.

In the end it was a teaching event, and at least i got to point out to one student what i did wrong.

[RedTRex]

I told you! ....... this car is very happy to snap throttle oversteer.

What RSB do you have on it right now?

[Amalfitano]

I'm not convinced yet it's all sway bar, but mostly due to too many variables, including ME, but it very well could be the majority of the culprit. I've got the M3 e93 bar on there

[Amalfitano]

By the way, with the ride height correct, no dynamic rubbing with the 255's up front and 275's in the rear. Though i have one guy locally telling me to cut out this STU crap and let him take a saws-all to my fenders and go BSP with some hoosiers.

[bradford]

Originally Posted by GaryS

Ah, it appears that we do have a consensus.

Sorry to get your hopes up, but I dialed out some rebound from the rear suspension and it turns out my fears were unfounded. I ran two different tracks this weekend with no noticeable problems with picking up the inside wheel. I'm at (-7) of 30 clicks on the suspension so there's tons of additional headroom there if I want to dial it down further as well.

The car's running like a raped ape. I didn't give a single point-by all weekend, and there were fully prepped 993 race cars in our instructor group. Considering I drive my car to work every day, through Chicago winters no less, I'm *extremely* happy with the way the car is set up.

[bradford]

Originally Posted by Amalfitano

By the way, with the ride height correct, no dynamic rubbing with the 255's up front and 275's in the rear. Though i have one guy locally telling me to cut out this STU crap and let him take a saws-all to my fenders and go BSP with some hoosiers.

What are the tire specs for the 255s up front? And what ride height?

[bradford]

Originally Posted by Amalfitano

Yikes! Failed exercise in rear end control Spun three times in 2 runs.

What were the circumstances of the spins? Drop throttle oversteer or power-on? This is just autocross, correct? Tire compounds, pressures, and temps?

Autocross isn't really a good opportunity to learn a car or set it up, IMHO. You get just a handful of runs and they're usually spaced out so you can't get the equipment to operating temp.

[Amalfitano]

Originally Posted by bradford

What were the circumstances of the spins? Drop throttle oversteer or power-on? This is just autocross, correct? Tire compounds, pressures, and temps?

Autocross isn't really a good opportunity to learn a car or set it up, IMHO. You get just a handful of runs and they're usually spaced out so you can't get the equipment to operating temp.

Precisely, i'm not about to put too much into what happened this weekend.

Morning runs (the spins), was before the warm front came through sunday, i think it was 52-55 degrees. I started at 39 psi all around just as a baseline. They are 255/35/18's up front, 275/35/18 in the rear, star specs, i didn't bother with too specific of a ride height measurement since i'll be getting corner balanced, but if you have AST 4100's, with the tape measure clip firmly against the notch that the shock body has between the threaded collar and the lower part of the shock, it was 3 and 13/16" to the base of the spring perch. I was focused more on getting the heights even and higher in a pinch and running out of daylight.

The spins were power on. Cornering i had no sensation of losing the rear end, it was really only when i got greedy with feeling out how much power out of corners i could deliver, and my issue came front say late apexing into a reasonable straightaway and trying to feel how close to wide open i could get. I think part of my problem is my brain adapted pretty well to the throttle by wire behavior of the car before, so that momentary delay between foot input and power isn't as precise anymore. Before if i wanted a good 1/3 i got to it just fine, anticipated the delay to get it going when i wanted. Right now there is so much different I just haven't gotten back to that smooth input yet.

I'm still confident this was mostly my fault for not respecting how cold the tires were.

This weekend I'll be aligned, corner balanced, and we should have near 70 degrees, though Joliet might have some showers. One of the STU guys in an e36 m3 might co-drive with me, which'll help for sure. He's unfortunately moving away, so his car isn't fully prepped for the season since he'll only be in the area for one event.

By the way, general advice: There is nothing better than getting an experienced driver to beat you in your own car. Swallow the pride and learn as much as you can. It also then feels awesome if you catch back up and best them.

[Amalfitano]

Originally Posted by bradford

Sorry to get your hopes up, but I dialed out some rebound from the rear suspension and it turns out my fears were unfounded. I ran two different tracks this weekend with no noticeable problems with picking up the inside wheel. I'm at (-7) of 30 clicks on the suspension so there's tons of additional headroom there if I want to dial it down further as well.

The car's running like a raped ape. I didn't give a single point-by all weekend, and there were fully prepped 993 race cars in our instructor group. Considering I drive my car to work every day, through Chicago winters no less, I'm *extremely* happy with the way the car is set up.

Negative seven from full stiff?

[bradford]

Originally Posted by Amalfitano

Negative seven from full stiff?

Yup.

[GaryS]

Originally Posted by bradford

Sorry to get your hopes up, but I dialed out some rebound from the rear suspension and it turns out my fears were unfounded. I ran two different tracks this weekend with no noticeable problems with picking up the inside wheel. I'm at (-7) of 30 clicks on the suspension so there's tons of additional headroom there if I want to dial it down further as well.

The car's running like a raped ape. I didn't give a single point-by all weekend, and there were fully prepped 993 race cars in our instructor group. Considering I drive my car to work every day, through Chicago winters no less, I'm *extremely* happy with the way the car is set up.

Sounds good. Enjoy the Quaife. My route is the opposite. With LSD installed, now I'll consider a stiffer rear bar.

[bradford]

Originally Posted by GaryS

Sounds good. Enjoy the Quaife. My route is the opposite. With LSD installed, now I'll consider a stiffer rear bar.

I actually ended up with Wavetrac because the vendor ordered the wrong one, but I'm very happy with its performance so far.

[Amalfitano]

Soliciting opinions...

Toe Alignment (note: i don't care about street wear):

Toe out in front at .15 degrees

Toe in for the rear at .15 degrees...

Camber will be max up front (probably 2.7) and 2 degrees rear.

[bradford]

I'm running zero toe up front, 3/16 total in back.

2 degrees in the back will be tough to get without adjustable toe links.