I just ran at Infineon Raceway for the first time and I could use some help with fine-tuning the car. I still need a ton more seat time, but I believe there are a ton of little things I can change to better my times. The car was a beast in the straights, especially coming out of turn 6 and 11. I was also out-braking most when coming into turn 7 and 11. My biggest trouble spot was the wide left between turn 1 and 2, as well as the slalom S's. The car understeers and I can't plant the nose into a turn.

My full build list can be seen here

I'm running Hankook R-S3, 265/35/18 in the front and 285/35/18 in the back. My camber was set to -2.0 all around. Next time I'm going to try -2.5 in the front.

My Hotchkis sway bars are set to 3rd stiffest in the front (4-way adjustable) and middle in the back (3-way adjustable). I can try tightening up the rear sway bar to full stiff to help reduce oversteer.

My shocks/springs are Tokico D-Spec with matching Tokico 375lbs springs all around. I don't think this is the best setup for me, especially the spring rate. Since my car is very front heavy with the Vortech, I might be better suited to KW Clubsport which is 855lbs front and 455lbs rear.

This car has so much potential...with a good driver After I tune the suspension and fix these issues, I'd like to go back to Laguna Seca and really put some power down.

 

Obviously, seat time is the most important aspect. I did notice that you said understeer was a big issue but then you mention loosening up the rear sway bar to help reduce oversteer.

If you are talking power induced oversteer, throttle management is the first thing to learn. If you are talking the car is loose in the rear, then yes, soften up the rear or stiffen the front (rollbar setting and spring rates).

If understeer is the issue, want to stiffen the rear of the car and get it to rotate.

Just general stuff since I don't know much about the d-specs and spring rate recommendations for your setup.

 

Yup, I said soften the rear sway bar when I should have said tighten it to reduce understeer. I corrected my original post.

 

Back off the front bar , move the front camber to -3 to reduce under steer on entry , reduce the rear bar and back off camber to -1.6 to get traction on corner exit.

 

I will try this.

More info: my Tokico D-Specs are 8-way adjustable. I had all corners set to 2-clicks from full firm, then tried dropping the fronts to 4-clicks from full firm. It didn't seem to help much.

My tires were set to 30psi front and 32psi rear. It's just a guessing game until I get a pyrometer.

 

I run the same tires, but a 275 front and run 34 hot front and 33 hot rear. Damper settings, start soft, work up. I don't see a diff listed in your mods , get one!

 

You must have missed it. Quaife LSD.

 

I Usally run 38ish hot on my RS3s

OP When are you gonna hit
Thunderhill?

 

No plans yet. Thunderhill is 3.5 hours each way. That's a bit far.

Another note is I noticed my power steering fluid was boiling badly after each session. I might invest in a larger cooler and mount it next to my intercooler.

 

Where do you live?

Be careful of sound at Laguna when you go. Most days are 92dB, some are 90dB. That's not very loud. I run my RS3s (285s all around) at 34/32 hot. The Z is capable of making up a lot of ground on other cars in the braking zones, even when outmatched by 2x the horsepower! Have you ever seen this?

http://www.youtube.com/watch?v=kw0k4PnNUSw

 

I'm in San Jose/Cupertino. I went to Laguna Seca last year and blew a 103db on a HKS exhaust, HFCs, and an open bypass valve. I'm now on a Bassani, ART pipes, and a silenced BPV. I have a pretty good shot at making sound this time.

That 458 was all over the place. Definitely a big difference in driver skill there. Were you running your 355mm brakes in that video? What pads? I'm on OEM Brembos and ran with Stoptech 309 street pads and I was still outbraking everything except GTRs and GT3s. Most passed me on corner entry and exit though.

 

You should join us at T-hill sometimes then, as it's only 2.5hrs driving or about 3hrs towing. I love it there.

I only have the 332mm kit, on Raybestos ST-version compounds. I do like the 309, but if you push them a bit, they will fade on you. The other pads have a lot more bite as well, so even deeper braking.

I like to make my 3/4 shift going up the hill at Laguna, but when I've set my fastest lap times on sticky tires, I was ready for 4th way before the sound check, so had to slowly shift AND head to the left of the track. It works, although it's not ideal for a fastest lap.

 

Let me know when you go up next. Hopefully track days are cheaper at T-hill than LS and Infineon...I've been paying $340 a day.

The Stoptech 309s didn't fade on me until the last lap of each session. They held up well. I might try Yellowstuff next event. I would like to get XP12/XP10 but would need to match them with new dedicated rotors.

 

use centric blanks with XP10 F/R. What brake fluid are you currently on?

you should sign up for june 30th-july 1st thunderhill weekend with NCRC! you too, Scott. Itll be my last time at a NorCal track until summer 2013

 

I think the front of my car is too heavy for XP10s in the front. XP10s are for cars around 2900lbs. I'm around 3250lbs and most of that is in the front now with the Vortech and extra coolers. XP12 in the front and XP10 in the back should be good.

Why the year long hiatus from racing?

 

Square tire setup. Put 285s on the front of the car.

 

I don't think I can. I have Enkei RPF1 9.5" +15 wheels in the front. I was running a 275 tire up front for a year and was rubbing on anything less than -2.2 camber. My front fenders are even rolled.

 

You can fit 285 rs3 on a 9.5 rpf1. I'm on XP10 and have no problems, there's a lot of people on the forum with xp10 too.

 

If you want to get rid of under steer you need more than -2.2 camber

 

I'll run -3.0 on the track but this is also my daily driver and would like to keep the front at -2.0 when on the street.

Everybody will say run two sets of wheels, two sets of rotors, and two sets of pads but I like being able to drive to the track as-is, race the hell out of the car, then drive to work the next day. That means making some sacrifices on tires.