im getting fairly frusturated trying to launch my 94 at the track!!!, I switched out my street tires of a set of Mickey Thompson ET Street Radials, and started at 18psi tonight and went down in 1psi increments, i went all the way down to 12 psi and didn't have any changes. 60's at every psi from 12-18 were about 2.2xx seconds with conciderable ammount of spin but no hop, these are the exact same results i was getting with my super hard street daily driver tires. I tried staging at about 10% throttle, and once the tree lit up i went WOT, and started spinning like crazy, i let off the throttle to about 75-85% and then got back on it again and it would seem to hook up okay then, but this is still not okay, i cant get off the line with out spinning like crazy and when i let off the car shifts early into 2nd gear, which doesnt help at all. I tried launching a few times at only 65 and 75% but would still spin off the line and the 60's would be even slower (2.3-2.4) Im not sure what to do to fix this issue, even at 12 psi im getting a lot of wheel spin and this is killing my performance. Oh yea, i also marked the tires and wheels with shoe polish and am getting NO slipping of the tire, i am running tubless and used permatex High Tack to glue the tire to the wheel.


As far as tonight goes it was 60* F out side, altitude is 1500', and as far as for burnouts i was bringing the rpm up to 2800-3200 for about 4 seconds, i went around the water box and kept all 4 dry, and i'm leaving on the motor.


I am willing to try any suggestions you may have to help fix this launching problem.

 

i pulled the M/T's off today and threw my street tires back on, i took some pics of the M/T's, it looks like the rubber was balling up more on the outsides of the tire and not so much in the middle, is this normal wear, or does it look like i did too much of a burnout? to little? should have done it in the water box? or is this normal?

 

that wear looks pretty even to me. wat suspension mods do u hav? rpm u leave at? and do u hav any videos? cuz all i can say now is to go through the water box and try a nice smokey burnout wit the tires at 15psi and c how it does. but answer those 2 ?s so we can see everything u got

 

it is stock suspension, and it looks like the car has been lowered with out using a LCA relocation bracket, so i'm ordering a set of those and hopefully that helps out a bit, As bar as the burn out goes i have been holding the footbrakes and running the rpm up to about 2800-3200 for about 4 seconds, and doing this with the tires dry (going around the waterbox), and for staging i have ben holding the footbrakes and bringing the rpm up to about 2500rpm then droping the brakes and going WOT.

You think i should be doing the burnouts with these tires wet? What about how to leave? Hopefully this helps and the relocation brackets help too

 

Are those pictures of both tires, I'm assuming so? The first two pics look like there wasn't any contact being made on the center stripe. The other looks more even. My initial thought is you might not be getting the tires sticky enough. Andyour pressure may be a tad too low as well, since the center of the one tire looks untouched. Tryexperimenting with doing a longer burnout to get the tires hotter,with and without water.

 

yea agreed longer burnout and more air pressure 12 psi is real low but i dont think u should hav this big of a problem leavin at 2500. u could also try buyin a set of adjustable shocks for the rear so u could play around wit it to try and help. here at atco we hav no choice but to go through the water so thats y i said get the tires wet

 

okay guys, thanks for your help, i'll bring the pressure back up to about 16 to start and try a longer wet burnout and see if the LCA's and relocation bracketsthat are inbound help out, thanks

 

Half the problem is the tires, I know the tire, Brian has them on his 69 SS chevelle, there a great street tire, but still a hard compact tire, the ET's are the tire to get not the et streets.. Try that and you'll notice a HUGE difference. Also, stock suspension is pretty stiff, a little softer will help preload,

 

the MT ET street is the softest DR you can get. softer than nittos and BFG's. he should be able to get 1.7s on that if he learns the powerband. a buddy of mine runs that on nittos.

i would bet he is seeing wheel hop. when i switched to DRs i couldnt get my 60' down for the life of me until i got my reloc brackets. but then the clutch started going out and the tune was off..... so i would always bog. well see what I can get on nitto 275s before winter hopefully