ed devinney

It's been about 5 years since I last had a 993, but my recently acquired car has some funny handling and steering feel that I don't think is normal.

At almost any speed, reasonable applications of the throttle and trailing throttle will make the car noticeably steer - L on application and R on TT. This isn't throttle-steering per se, I have a decent amount of track and skidpad time to know that pretty well. It happens with fairly gentle throttle changes. I thought it might be the ltd slip diff, but my 951S w/LSD is rock solid.

In general the car doesn't feel as well planted as my old one. The old one had 15k mile on US M030 shocks, RoW springs & was lowered and aligned to RoW spec, this has 36k mile US standard suspension. I will do a Bilstein + RoW springs but wonder if there's something to look at now & recall reading that bad kinematic toe settings made things squirrely - might this be what I'm feeling?

Thanks!
Ed

Mark in Baltimore

Ed,

Definitely check the kinematic toe. Which shop do you use?

Ray Calvo

Could also check tire pressures and tread depth; differences in rolling diameter left to right could bring this on.

Also, most high performance tires are intended to roll only in one direction. Check the directional arrows imprinted in your sidewalls.

Jeff96-993

Everytime this has happened to me it was always as Ray described, improper air pressure between the left and right rear tires. Give it a check.

GrantG

Sounds like kinematic toe to me too (unless air pressure cures it - that's cheap to try...)

ed devinney

Ta da! Rears were grossly underinflated & different side to side, I'll need to keep my eye on them.

I feel like a bit of a boob for not checking the obvious, but thanks for the suggestion, guys..

Mark - I've gone to Tom at Redline in Purcellville, VA for the last 8-9 years. 2 miles away from home and he has a bunch of 911 and 951 experience. Apparently his new alignment rack will do KT, too.

Jack Esposito

It is difficult to tell just by looking at the low profile tires when they are under inflated, especially on the back. But it sure does affect the handling when they are low.
Another thing to watch for is mismatched tires. Had a set of Bridgestone SO2's on my car it handled funny like the pressure was low. Kept checking air pressure and it was fine. Finally realized one of the rear tires was a Pole Position and the other was a Porsche N2. Once I got a matching set on the back the handling problem went away.

Jack