Ok so basically I changed from a 26x10x15 mt drag slick (with tubes) to a 28x10.5x15 (no tube)
and I have been having trouble getting these tires to hook up on the line. Nothing major, maybe 1/2 - 1 rotation before it hooks up, but in bracket racing it can be killer.
Keep in mind the old 26" tires I never had problems with (and thinking about putting them back on)
im running about 13 - 13.5 psi
car will do 1.57 60' on average

suspension wise there is an aftermarket torque arm the bolts to the floor board, aftermarket Lakewood rear shocks (drag non adjustable) Iv replaced all the bushings. And recently added relocation brackets for the control arms.

Can anybody help with my issue here? Tell me what To try.

thanks

 

Are they both MT slicks? Different tires can have different compounds so that could be part of the difference. Also, the tubes do make the side wall stiffer so that could be a factor too, esp with our "heavy" cars.

It sounds like your suspension mods are pretty standard and should work fine. Did you make any changes between tires? I wouldn't think the tire diameter would matter that much but possibly need a change to the LCA mount point.

If you don't mind tell me more about your setup and what size rims you have each tire on. 1.5x 60's isn't bad and a little wheel spin can be helpful with a stick or trans brake car. Has it been less consistent?

 

Are you on the same rim?

 

Can you have someone film your launch with a high speed camera

 

The wheel is 15x8. Both same Mickey Thompson tires. I called them and they said the 8" wheel should work fine.
Only thing that was really changed was having bte go through my converter. They said they made it a little looser (was originally 3200 stall) but I don't know how much they changed it. It's on a th350.

Down track had been pretty inconsistent lately this year. But I'm saying that's cause by having someone rebuild my carb and he tried to tune it without having the motor...I'm in process of undoing everything he did

 

Get motor figured out first.

What does the control arm angle look like? What hole are you in on the bracket? Is the rear getting any separation

 

It's in the middle hole. The rear of the control arm is angled down. (Before it was slightly angled up)
I tried the bottom hole and I was told the tires were wrinkled while staging, so I put in it the middle and seemed to help it.

 

Wrinkled while staging?? Might be way low on air pressure