Why am I bouncing?

[Firecat F7 Viper]

I recently checked my tire pressure and noticed they were around 22psi.
I added air to bring them up to the correct pressure of 29psi. It seems like ever since I did that, I have been getting a lot of wheel hop if the tires start to spin or I shift hard from 1st to 2nd. I have to let up on the gas for fear of something breaking...it bounces pretty bad sometimes. Especially when it is cold out.
Does anyone know the cause of this?
I am thinking of deflating the tires back to 22psi. Will this lower pressure hurt the tires or result in poor handling? Other than that, what else can I try to reduce the wheel hop? I think I read in an old post about bushings or something might be the cause.
The tires are original 1998 michelins with only 4200 miles on them and 70%tread left....could the 6 year old tires be the problem?

 

[99 R/T 10]

The tires are original 1998 michelins with only 4200 miles on them and 70%tread left....could the 6 year old tires be the problem?

Yes. Get some V700 Kumhos from Luke at tire rack or JonB at Partsrack........................... NOW!!!!!!

 

[ohiodoc]

Are the Kumhos good tires. I see they are really cheap.

 

[Jack B]

Excessive toe-out in the rear can exacerbate wheel hop. When was your last full alingment.

 

[PhilC]

. Especially when it is cold out.

That's the answer. It's always that way in the winter. I'd say dont wory about it and just go a little easier on it during the winter. Come spring it'll be back to normal. I'm not saying dont get tires and check alignment because both of those things are god things to do, I'm just saying that less traction when the road surface is cold is to be expected.

 

[Jay Herbert]

The tires are original 1998 michelins with only 4200 miles on them and 70%tread left....could the 6 year old tires be the problem?

Yes. Get some V700 Kumhos from Luke at tire rack or JonB at Partsrack........................... NOW!!!!!!

One minor thing to keep in mind on the Kumho's, they are "WR" not "YR" or "ZR" rated.

W - 168 MPH
Y - 186 MPH
Z - 149+ MPH

For most Viper owners (most RT/10's) this would be fine.... but some who tend to "completely enjoy the capabilities of their car" (particularly coupes or upgraded cars), Z rated (for their own safety) would be required if I interpret the rating system right. The rating systems is a little bazaar, as W appears higer than Z but Z is 149+, W is max 168. Maybe a tire guru can clarify?

I have Dunlop Sport 8000's on my car and really like them.