Swaing down the track

[microELVIS]

The car was all over the track last time out. I was using 26x8.5 slicks that were near the end of their use. I have 245/60/15s in the front so they are taller then the 26 in the rear. There is no airbag, and have new rear kyb shocks.

Is the swaying caused by bad bushings, short tires compared to the front, worn tires maybe? Just looking at a direction to take,
I was thinking a 28 tall tire would help, since my fronts are taller then 26. But I know the rubber (bushings) is getting old now as well.

Any suggestions

My best run that night was 13.15 swaying all over

104mph
1.9 60 foot
17psi

 

[XLR8]

How much air in the tires? I ran once with 10# of air in my Hoosier QTPs and the car was doing the happy dance on the big end. I try to keep the air pressure between 13# - 15# - the higher the better as long as I can hook.

 

[microELVIS]

Ya it was about 13# not much more then that. I have to say, the tires look small when you stand back a little, but look big when they are off the car.

 

[Slow91z]

Low tire pressure, does it.

Having bias-ply tires and radial tires on the same car does it also.

It's best to run all bias ply or all radial tires...At your speeds I would say you probably just need more air pressure, I can get a 1.9 60' with 20 PSI in my slicks (26-10.5).

Was it spinning, or was it just slow to spool??

 

[NEARING]

The 86T I had was BAD until I changed the worn out shocks.

 

[microELVIS]

Ya I had horrid rear shocks, I could push them in with my hands when i took them off. The tires did spin a bit out of the hole, I usually get a 1.8 60' with a tad of spin on average.

You could have a point of them being too low in pressure, but at 8.5 wide I wanted traction out of the hole. One guy at the track mentioned about the bias ply tires and radials, but like you said at my speeds it shouldnt make a difference.

Guess Ill just look fer bigger tires....

The car should be a consistent 12s the way its running now.

... Thanks guys

 

[norbs]

Buy e/t streets they have a stiffer sidewall and the car will sway a bit less, try the tires at 14 psi.

 

[fubar2.5]

Also check your body mounts.

 

[microELVIS]

Ya actually, I had all the body mounts filled in a few years ago. I was missing 5. Definately good advice for someone who hasnt done that.

 

[NJVetteGuy]

I run ET streets on my C5, if I don't have my bias ply skinnies on the front the car dances like crazy, especially on the big end. I run 15-16 lbs and get the best hook at that pressure. My best 60' with that car is 1.52 on 26X11.5-16s. Once I make my T fast I'll be shooting for similar 60' times