gtred

This will be the second HPDE for my 996 trackday project. The last time I set it up without much advice... and it drove pretty horribly. Too stiff. It just bounced in the corners. This time I've gotten a little help(from friends and Rennlist forum member input). I've also had time to street drive the car a little.

Front: Bridgestone 235-40-18 Re71R set at 27# cold. Target 34 hot. 600 lb springs. JRZ doubles set: 4 compression, 8 rebound. GT3 swaybar set 1 off of full soft.
Ride height: 110mm
Castor: 7.9 degrees
Camber: -2.0 degrees
Toe: 0
Rear: Bridgestone 275-36-18 Re71R set at 27# cold. Target 34 hot. 700 lb springs. JRZ doubles set: 4 compression, 5 rebound. GT3 swaybar set 1 off of full soft.
Ride height: 125mm
Camber: -2.5 degrees
Toe: .34 degrees total toe in.

The car seems very firm for the street, but I wonder if it'll soften up too much at the track. (?)

I do still have some trouble with the front tires grinding the fender liners at full lock. Unsure what others do about dialing back castor. The Tarret adjustable caster pucks are nearly maxed out. It makes me wonder how some are able to fit 245's on the front.

Does anyone with similar equipment wish to comment?

josserman

What wheels are you mounting the RE71's on? Sorry still learning about 911 setup so can't help much, if you're running at any NE tracks I'd be happy to make some general track specific suggestions. I'm surprised with those rates it felt so stiff, but again sorry I'm just starting to learn about 911 specific setup.

gbuff

Not well versed on 911s but in general just looking at the numbers you could prolly still use more front camber, especially if you have a lot of wear on the outer portions of your tires. This could potentially let you run lower pressures, giving you more grip and softening things a bit; remember, the tires' spring rate (determined largely by pressure and sidewall height/stiffness) are an integral part of your total setup. Just take a look at the size of the sidewalls on an F1 car

Gary

gtred

Wow!! What a difference!!! The car went from evil to angelic with just a few clicks of the shocks / bars and a change in front to rear camber. The car was planted an definately at a baseline for further fine tuning. Thx all for your input.

gtred

The car handled well enough to send my friend out in the novice class with no issues... another Porsche beliver/enthusiast in the making.

awrryan

Bill Lehman

I don't remember where I found this but "Shock setting in one sentence:Add rebound to unstick an end; remove rebound to increase traction. When working with adjustable shock absorbers, start at full-soft and stiffen as needed."
To help add camber as well as move the top of the wheel in add camber plates.

Nickshu

I have the same car and I am setup at -3 front camber and -2.5 rear. I have run the same tires (RE-71r) as well as R7 slicks and the car feels well planted on the track. My spring rates are 400/650.

The front rubbing could be solved by either getting rid of the GT3 LCAs (if you are using them) and going to adjustable top mounts because the GT3 LCAs will drive the front wheels forward in the arch. You could also replace the tuning fork arms on the front with adjustable ones, that would solve the issue too. I don't have GT3 LCAs...I run just the top mounts and can get -3.5 with them max.

I have GT3 adjustable sway bars too, I run them at the stock GT3 settings ( can't recall the setting right now) but I have thought of changing them b/c when on track with street tires I get a little more understeer, but on slicks I don't notice it at all. (Or I'm too far from the tire's limit to notice).

gtred

Hey Nick, nice car! Yes, that looks to be the same trim package as mine. Blue wheels, dash bits and console and wing. It seemed a little overstated for my taste initially, but it's grown on me; especially for a trackday car. I couldn't believe how heavy the factory seats were when I replaced with race seats. I do have both front camber plates as well as gt3 lca's with an approx 1/4" shim. I did also get the Tarett caster adjustable puck, so I could bring the wheel back a little more by adjusting for less caster. I'm wondering how low of caster angle to go before if effects straightline trackability. Any suggestions on appropriate further mods would be well received.

Josserman: I'm just using stock wheels.

Awrrayn: Yes, I think it's close enough that "one thing at a time" is possible.

Bill: I am so glad that I didn't get 3-way shocks... 2-ways have me chasing my tail already. I couldn't imagine the set-up headaches with even one more ****.

gtred

I had the car out all day for a t/t. It ran/drove well right out of the box as set. Then when I began to pick up the pace I noticed that it was getting light and funny in the rear end under heavy braking. 2 clicks more rear rebound and the car settled down and stayed planted. After awhile I began to really trust the car... and I got to the point that I was actually driving this heavy, under powered, spiffy little car very fast... right at the limit. It was easier to steer by throttle than I had originally thought.. I had imagined snap oversteer with any throttle changes, but pleasantly found that you could work the throttle to point the car just like the front engined cars I had raced. For a day... I was a Porsche God! (and humble!) Thanks all on getting me set on the right path.