85 vette –I was in the turning lane making a left hand turn the light turned yellow and I accelerated just a little bit more than normal turning before it turned red. The back end whipped around slightly during the turn. I let off but I really didn’t even throttle it to begin with. This has happed a couple of other times when turning. I have Kumho Ecsta Supra 712’s. Are these tires know for not gripping in turns. They seem pretty slick when turning from a stop.

 

That usually happens to me when Im not "trying" to do it.

 

Hell, turn into the skid and give it a little more gas. Looks cool and gets the heart a pumpin! Watch out for curbs though.

 

You say that like its a bad thing...

 

Thats what I was thinking. When i first got my vette I did it all the time not meaning to do it. You just get used to it because its different then a normal car. Now I love doing it

 

Two years ago when i was 17 i had a 94 LT1 Firebird formula and the first time it rained i took a turn too fast without any gas and lost the back end. ended up fish talling back and forth a few times before gaining control again. Had a buddy in the car and he screamed out "that was awesome". did it all one handed too. now that i have a 96 vette i have the ASR and don't have to worry about that as much anymore.

with new 712's you should have been fine unless you got on it more then you thought you did. if not it might have been oily or something from traffic. anyway just be careful when doing that stuff b/c one time you might not be able to control it.

 

I don’t want it sound like it was a bad thing. It’s pretty hard to keep from grinning as you go on down the road and see everyone in traffic just staring. I just wish there wasn’t so much traffic around so I could have a little fun with it. Just seemed like it gave up the traction really easy. The 712's are old and have just a little more left to reach the wear indicator on the tread. I haven’t seen a new one to compare the tread depth. I am thinking that tires maybe in my future real soon.

 

Part of your problem is the Posi-Traction rear. Both tires brake loose at the same time giving you no rear tire grip at all. If you had an open rear only one tire would spin leaving the other to grip the road.

 

it happened the same way to me a few years ago but with different tires.

 

Whil;e the 712's should work fine in street drivng, their tead compound is pretty hard so they can give good tire life. What tire pressure are you running in the rear? Try 30psi and see if that helps.

 

LOL, "I wasn't trying to Officer" "I just got this car and Im not used to it yet".....

Worked for me...Twice

 

This is true.

Larry
code5coupe

 

There was likely something on the road.
Either sand, oil or something from a recent accident.
I know there are a few intersections around here where I can get get on the gas hard and not have a problem and others that I seem to slide around without trying.
Always be ready for the rear end to break free accelerating around a corner, it's part of owning a corvette. (Unless you have ASR)
I also have the 712's and the rubber compound definately seems not as sticky as they get older and the tread wears down.

 

I'm running the same tires and have experienced similar problems when the tires are "cold"... They seem much more prone to "break loose" for the first 5 to 10 miles or until they have warmed up a bit.

 

We used to run the 712's on our BMW but now run the ASX's. The 712's wore quick and (when worn) were down-right scary in the rain.

If you want to keep the ***-end from comin' around on turns, leave the ASR on (if you have it) & keep your foot out of it. Other than that, enjoy the ride!

Bottom line; new tires will help...alot.

 

Old hard tires, something on the road, alignment maybe. How long has it been since an alignment? I had old hard tires on mine and the back slid around a lot. My alignment was way off to: rear toe drivers side .02", passenger .21". With new tires and an alignment the "problem" is much lessened.

"Part of your problem is the Posi-Traction rear"

I thought all C4 Corvettes were limited slip?

http://forums.corvetteforum.com/show...ip&forum_id=48

 

give it more gas hand have some fun

 

The first day I had my vette I did the same thing on accident! I made a right turn and gunned it a little too hard. It scared me at first, but I was amazed how when I corrected the steering it shot in a straight line! I love my c4!

 

Sounds like you need to find an autocross.

www.myautoevents.com

there's gotta be some in your area.

 

welp... all vettes are LSD, not posi. There is a difference. However, under these conditions, it's irrelevant.

The rear end WILL kick out to the right. This is a result of torque vectoring off the rear differential housing.

A couple of ways to minimize it:

1) Make damned sure all the rear bushings are good. Including the rear diff carrier bushing.

2) Be sure all C-Beam bolts are TIGHT!

3) Upgrade to "beam plates," available from www.zfdoc.com. These will help to distribute load better through the C-Beam and reduce that right rear pull.

The 712s are not the cause of this, an overactive right foot is 90% of it.

Due to the C4's rather short wheelbase, it is very prone to this condition. The solution is to be cautious on a corner. Especially one where you can't see what is down there... and if you have cold tires.

The idea behind the LSD is to allow the rear wheels to rotate at different speeds when the car is turning (the outside wheel travels farther than the inside, etc). A true posi will create a nasty vibration as the tires skip, because both tires are connected solidly.

I am about as sure as I can be that Posi was GM speak for LSD. I have driven a number of older cars with "Posi" and they were no where like the one van I drove with a welded rear!