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GT3RS Understeer Cured (and how)

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Old 08-29-2007, 09:06 PM
  #46  
Larry Cable
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so is the general concensus then dial in the manuals 'track' specification, set sways to '1 off' full slack front, fuill stiff rear and things get a lot better?
Old 08-29-2007, 09:16 PM
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Bob Rouleau

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Larry - On street tires I went as above except sways full soft in front and full STIFF in back. This helped a lot but the car needs real R compounds to work right.
Old 08-29-2007, 09:20 PM
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Larry Cable
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jeez ... surprised at the 'full soft' on the rears with streets ... I got stuck with the Corsa R's ... dont particularly want to go to an 18" wheel just now ...



thanks
Old 08-29-2007, 09:43 PM
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Arrgh typo! Full stiff in back full soft in front to reduce understeer. Sorry.
Old 08-30-2007, 12:09 AM
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are you running 8.5 or 9s in the front? assume you are running 12s in the back. These tires are slightly shorter than stock so you may get a bit more torque out of the corners. The wider fronts will improve braking as well. Look forward to your report after your Glen event. Would be great if you also ran RA-1s for a comparison. The 888 are softer so they probably grip better but the RA-1s will last longer.


[

QUOTE=stisseront;4438968]Just got a set of R888. F:255x18, R:315x18. They seem to be fitting pretty well. No rubing in the front (at low speed at least). Will be going to Watkins Glen for three days in 10 days. Tires will be shaved. I will give some feed back upon my return. Has anyone tried this?

Stephan[/QUOTE]
Old 08-30-2007, 02:12 AM
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Originally Posted by Bob Rouleau
Arrgh typo! Full stiff in back full soft in front to reduce understeer. Sorry.
i jsut moved to full soft up front as well.
Old 08-30-2007, 02:13 AM
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Originally Posted by Larry Cable
so is the general concensus then dial in the manuals 'track' specification, set sways to '1 off' full slack front, fuill stiff rear and things get a lot better?
larry, get your car to tony c and it will drive a hell lot better.
Old 08-30-2007, 03:00 AM
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mooty, i will be tracking my RS at a few of the cal tracks soon. Do you have some reference lap times running on the 18's for me to base against? I will be running track suspension settings on MSPC 19". Willow Springs, Buttonwillow, CAL Speedway and NO cal stuff. Thanks, Stu
Old 08-30-2007, 05:16 PM
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i only have time for track nor cal tracks.
at LS, with lifting for sound, 1:42
at TH with cyclone, 204

both were on toyo RA1's.

car is stock other than safety equipment, tire and pads

i think i am at least 4 seconds off pace.
Old 08-30-2007, 10:19 PM
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thanks for clarifying Bob ... funnily enough when I was back in the UK about 6 years ago and I had a mkI clubsport I ran it with this config at Bedford autodrome ... what a nightmare ... car was nearly undrivable!

I can see an alignmnent for my baby in the near future!
Old 08-31-2007, 12:42 PM
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Why aren't the factory settings and tires the best for the RS performance parameters? One has to believe Porsche spent considerable time in selecting what is best for the car. I read that when Porsche develops a car it starts with the tires.

So what is going on here. Is the car being modify to accomodate the driver skills?
Old 08-31-2007, 02:01 PM
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Originally Posted by Nick
Why aren't the factory settings and tires the best for the RS performance parameters? One has to believe Porsche spent considerable time in selecting what is best for the car. I read that when Porsche develops a car it starts with the tires.

So what is going on here. Is the car being modify to accomodate the driver skills?
to some extent yes, to some extent no.
i spoke with several p car factory drivers and the short of it is, get BBS motorsport wheel, put slicks on, then just drive the **** out of it.

however, the factory certainly cannot put slicks on RS and get it to pass DOT.

that's one example.
Old 09-03-2007, 01:33 AM
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Originally Posted by Nick
Why aren't the factory settings and tires the best for the RS performance parameters? One has to believe Porsche spent considerable time in selecting what is best for the car. I read that when Porsche develops a car it starts with the tires.

So what is going on here. Is the car being modify to accomodate the driver skills?
Fastest doesn't equate to safest.
Just like a set of "pro" golf clubs will make an average duffer look even worse the "fast" settings on any car will make the average driver spin out in least expected (for them) moments.

In DE we don't always teach the fastest line to green students as that often deviates from the safest line.

So Porsche releases the car with settings that will cause the unskilled driver the least amount of trouble.
Old 09-03-2007, 09:51 AM
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Amaist, Hope you had a good weekend at Calabogie, the weather couldn't have been better.
Old 09-03-2007, 12:44 PM
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Originally Posted by amaist
Fastest doesn't equate to safest.
Just like a set of "pro" golf clubs will make an average duffer look even worse the "fast" settings on any car will make the average driver spin out in least expected (for them) moments.
In DE we don't always teach the fastest line to green students as that often deviates from the safest line.
So Porsche releases the car with settings that will cause the unskilled driver the least amount of trouble.
Very well stated. The history of that decision is significant. Porsche suffered a multitude of lawsuits relating to accidents in their early 930's. Tons of torque and HP combined into a street car the likes of which most drivers had never previously encountered led to some horrific accidents. I saw one wrapped around a tree one early morning way back then. The litigations became even more prevalent when they introduced their Cabriolet version in the late 80's. Those cars lacked the intregal stiffness required to support the HP and torque. Porsche learned from their costly litigations and now understeer is a build standard on all Porsches....


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