Tire shake/shudder after car was already at full boost

[tonka]

Went to 1/4 mile track to work on launching. Was only time for one pass, weather wouldn't cooperate. Car hooked good off the line through spoolup, but somewhere around the 60ft mark shook the tires pretty good and had to get out and back in it. 60 ft was a 1.62. This was on 275/60/15 Hoosier DRs at 20psi, car has aftermarket upper & lower rear arms, pinion angle set, double adj. rear shocks. As you can hopefully see from Powerlogger screen shot, boost was full in prior to this happening, but motor was still coming up to peak torque. Is it a tire pressure issue? Does it just need more power thrown at it? My camera guy was not available, so no video.

 

[et10sec]

low air pressure

 

[tonka]

Ok, will try a pound or two extra in the rears this weekend and see what happens, thanks!

 

[Chuck Leeper]

" My camera guy was not available, so no video." A key to finding out what's going on..

 

[tonka]

Without a doubt, Chuck. I usually have someone available at that track to run the camera, not this time unfortunately

 

[sscamino]

Might want to check to see if you spun the tires on the rims.They make shudder sound.If cant tell mark rim and tire with yellow grease marker. You can have a tire shop break tire away from rim and apply rubber adhesive to the bead. You should be good to go,also easyer than puting screws in your rim.

 

[tonka]

Had not thought to check that, I will say though that added tire pressure cured the issue for me.

 

[sscamino]

M/T recomends 19-20# in there Drag Radials

 

[tonka]

I'm running the Hoosiers, 24-25 lbs seems to be where my car wants them at