Rear End Instability?

[Flavor 987S]

Originally Posted by Timbo2

Manufacture's spec is F29/R36. Where are you getting your info, or is this based on experience?

I guess I am wrong about OEM tire pressures for an 986. On my 987S with 19" inch wheels, OEM spec's are 34F/37R. I tend to run about 1 PSI lower than spec. Michellin PS2's.

Did not realize front tires pressures are so low (30 PSI) on a 986.

[Gilles]

Originally Posted by Flavor 987S

I guess I am wrong about OEM tire pressures for an 986. On my 987S with 19" inch wheels, OEM spec's are 34F/37R. I tend to run about 1 PSI lower than spec. Michellin PS2's.
Did not realize front tires pressures are so low (30 PSI) on a 986.

Flavor, also on the 987S w/19's
I found out that running about -1 on the rears (34/36) the tires wear more evenly, otherwise the rears will wear too quickly on the inside.

.

[Flavor 987S]

Originally Posted by Gilles

Flavor, also on the 987S w/19's
I found out that running about -1 on the rears (34/36) the tires wear more evenly, otherwise the rears will wear too quickly on the inside.

.

I've gotten great tire wear on the Boxster. My first set of OEM Pilot Sports lasted 20,000 miles. The PS2's look to do about the same. Now, the 911 Turbo eats tires. I'm lucky to get 12,000 miles. Same driving style....lots of highway with spirited sprints on country roads. Not complaining.

[Topless]

Originally Posted by thstone

Shifting in a corner at 115mph will definitely upset the balance. Get your shifting done before the corner.

Bingo!
thstone has been getting some good training. When you are going 115 even in a gentle curve the tires are pretty heavily loaded. It's a physics thing. Lifting the the throttle and shifting mid corner is a good way to experience the thrill of going backwards out in the weeds at 115. If this does not make any sense to you, a spring DE or performance driving school might be a really good idea.

[Timbo2]

Originally Posted by Topless

Bingo!
thstone has been getting some good training. When you are going 115 even in a gentle curve the tires are pretty heavily loaded. It's a physics thing. Lifting the the throttle and shifting mid corner is a good way to experience the thrill of going backwards out in the weeds at 115. If this does not make any sense to you, a spring DE or performance driving school might be a really good idea.

Thanks for the advice. I thought that now I have a Porsche I'd be invincible, but in fact I think I need to be more careful than before. Because it does everything so well it's easy to forget exactly what you're asking of it. (But I guess you new that already