how much difference does psi make?
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From: fortress of solitude
how much difference does psi make? well i went to the track and ran for the first time since my tune, and i got some dr's and TD's. ran twice since it was bracket racing and had 2 13.0 and i messed up both times. my best 60' was a 1.94 and my nittos has 30psi in them and i bogged. what difference would a lower psi (16 seems to be whats recomened) make? also what does a 60' translate to in a quarter mile
60' doesn't really translate a quarter mile...it just says how good of launch you get...there are people that will run 12's with a 2.0 60' and then there are people that run 12's with a 2.4 60' 
Marc lowering the psi in the tires will just make it hook harder. You said you bogged so that isnt an issue, even though 30 psi on Nittos is pretty damn high!! The thing that concerns me about your car is the trap speed with your mods. You should easily be pulling 112-114 mph but you arent. Are you still going to the track thursday?? If so we can try and figure out whats going on. I will go and see what I can do to help you.
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From: fortress of solitude
Originally Posted by 777
60' doesn't really translate a quarter mile...it just says how good of launch you get...there are people that will run 12's with a 2.0 60' and then there are people that run 12's with a 2.4 60'
Man you didnt do **** for those tires as for heat. Nittos need a loooong burnout to get hot, they are kind of hard in the performance tire world. How about we put my ET Streets on your car and that way you dont have to worry about it.
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From: fortress of solitude
get that one patched and we'll do it....someone still explain to me why my mph could possibly be so damn slowwww...
my only theory on that would be because my shifting was so "notchy" due to lack of pressure in the Master clutch cylinder. my reasoning is since it takes me longer to shift, i lose mph. i put an 02 one in with the drill mod and it shifts much better, but like i said i dont know if that will really do anything
my only theory on that would be because my shifting was so "notchy" due to lack of pressure in the Master clutch cylinder. my reasoning is since it takes me longer to shift, i lose mph. i put an 02 one in with the drill mod and it shifts much better, but like i said i dont know if that will really do anything
Launching!
Joined: Aug 2004
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From: Memphis, TN
Lets just wait until Thursday, where you can actually get a decent run in... Then maybe start trying to figure **** out.
You ran a 13.0 before your tune, nittos, and duals.... so it is obvious that your car has to be doing somewhat better. Get a good run in and then lets talk....
You ran a 13.0 before your tune, nittos, and duals.... so it is obvious that your car has to be doing somewhat better. Get a good run in and then lets talk....
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From: Winchester, VA
I think that recomended psi for both the nittos and gforce's are pretty similar. I have read not to go below 15psi beacuse there is a possiblity of the bead breaking due to lack of inner pressure. When I had my comp t/a's I ran them at 18, and they hooked up nicely. I would suggest 18psi, like Unit said.
Fry
Fry
Originally Posted by Beast
get that one patched and we'll do it
Haha ok I will get it patched but let me forewarn you. Going down the track on Et Streets is different than radials. On the big end of the track the rear feels like its floating on air. The back of the car sways back and forth and if you arent accustom to it it can make you feel a little uneasy.
Originally Posted by Beast
i realize that 60' doesn't make a quarter mile time, but everytime i ran a better 60' given all other variables the same i would have a better quarter mile time..remember wayne i spun like dog **** with a 3k dump and i warmed up the tires as best i could before..i bet 16psi would work muchhhh better than 30psi..its worth a shot anyway
You said that you werent spinning but I also thought I wasnt spinning to bad. You may not be, but I would try those m/t's.
I would also ride around a little while on the street with them, to get use to them.
Looks like there's only 2 more thursdays left, that means Ill make it the last day since this thursday my car will still be in the body shop. Hope to see you guys there.
Originally Posted by Drew98TA
umm... 60's do MAKE the quater. Its been said for every tenth you knock down on the 60ft you'll run 2 tenth's faster. Its ALL about the 60ft!
Basically I was stating that even if you 60' doesnt look to bad you may be spinning much past it. In my case I was spinning much worse after the 60' and actually shifted into 2nd too soon because of it.
Launching!
Joined: Nov 2002
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From: Fort Carson, CO
Sometimes spinning a little isn't as bad as you think, it'll help keep you in the powerband. Of course... lighting up the tires won't do you anygood. But bogging doesn't do much good either.
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From: Edmond, OK
I had 40 in my nitto 275s the first time I went to the track. Mostly because I didn't bother to check them. I figured they were sticky enough it wouldn't matter. Boy was I wrong. My best 60 that night was 2.1 and my friend was running 2.2 in his pickup with the stock tires on it. I run 18-22psi on the rear tires even on the street now unless I'm taking a long highway trip. As others have said the 60 foot can be a big factor in the race.
