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Best RPM for a Hard Launch?

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Old Sep 30, 2009 | 08:12 AM
  #16  
Hammerhead i-Eagle Thrust's Avatar
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you are supposed to
 
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Old Sep 30, 2009 | 10:04 AM
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on street tires, no you dont lower your tire pressures. on real race tires, yes.
 
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Old Sep 30, 2009 | 10:37 AM
  #18  
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false...you want more sidewall flex at the drag strip no matter what tires you have

if you were autocrossing or road racing you would add more pressure so you would have less sidewall flex
 
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Old Oct 1, 2009 | 04:11 AM
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Originally Posted by 00gts6speed
false...you want more sidewall flex at the drag strip no matter what tires you have

if you were autocrossing or road racing you would add more pressure so you would have less sidewall flex
My 60 foot times did not change at all when I lowered my pressure. I have tried 32psi, 25psi, 20psi, and 15psi, and there was virtually no difference. I now run with 30-32psi and get 2.1 60 foot times.

At best, it'll net a SLIGHTLY quicker 60 foot time, but idk... I only noticed a 0.01-0.03 difference with the lower tire pressure, and that could have been from heat or any number of variables.
 
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Old Oct 1, 2009 | 04:17 AM
  #20  
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^ interesting

i'll have to try myself as well.
 
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Old Oct 1, 2009 | 08:16 AM
  #21  
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every person ive ever talked to has said to drop your pressure into the mid-low 20s, 15 is too low for street tires
 
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Old Oct 1, 2009 | 09:19 AM
  #22  
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^ then i would go by what they say instead of what experienced drag racers do! Because we all know that street tires have flexible side walls, esp those 35-40 series tires we all are using. LOL!! Pass your BS on to other who dont know any bettter.
 
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Old Oct 1, 2009 | 09:32 AM
  #23  
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well 35-40 series tires suck *** for drag anyway...

im just talking about people who pulled great times in stock or near stock cars. also going to the track when its cold with summer tires is not the best idea
 
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Old Oct 1, 2009 | 12:38 PM
  #24  
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I run with 205/65/16's at the track.

Kuhmo Ecsta LX Planintums for $88 a piece from Tirerack

I also get no wheel spin off the line, and my best 60 foot is a 2.1.

I'm not trying to toot my horn, but I think street tires should not be messed with too much.
 
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Old Oct 1, 2009 | 01:11 PM
  #25  
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wow 65 profile...see thats why you have good times...everyone else is like YEAH BoI i gotz 20z why am i running 15s?..lol

how heavy are the rims?

maybe i will stick with my 15.4lb 17x8 koseis
 
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Old Oct 3, 2009 | 05:34 PM
  #26  
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Originally Posted by 00gts6speed
wow 65 profile...see thats why you have good times...everyone else is like YEAH BoI i gotz 20z why am i running 15s?..lol

how heavy are the rims?

maybe i will stick with my 15.4lb 17x8 koseis
I have no idea about the weight, but they were lighter than the OEM coupe 17's I had on at one point.

I would recommend keeping your rims.
 
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Old Oct 3, 2009 | 11:52 PM
  #27  
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yeah i think i am, i think the oem 17s are like 25-26lbs from what i read, so 15.6 lbs is like a 40lb unsprung weight redux

and the offset is pretty good at +35 also...just gonna have to deal with all the ballaz hating on my 17s..lol
 
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Old Oct 4, 2009 | 01:06 AM
  #28  
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6000rpm with a slight feathering of the clutch then full engagement. If the tires are hot and track prep is excellent I can foresee redline (7100rpm in my car) launches. I also run an OS Giken integrated clutch set-up.

Track ready:




On street tires I launch around 2800......but more throttle and clutch modulation is necessary to net the best 60's (I have pulled (2) 1.98's and about 392048209340923 2.0's).
 
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Old Oct 4, 2009 | 02:34 AM
  #29  
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I can't get better than a 2.200 on my OEM 19's with crappy Goodyear Eagle RS-A All Season's.

I've also messed around with tire pressures. Did me no good.
 
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Old Oct 4, 2009 | 05:44 PM
  #30  
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I once hit a 2.0 60' with my 5AT that had 3.9 gears w/ Goodyear Eagle F1 tires 285/40/19.

For an MT on an 05 revup with normal street tires I hold it at 3K RPMS slip out the clutch.. As soon is it grabs and car starts rolling and quickly fully release the clutch and floor it at the same time..

Its all in the feel.. You'll know. Key is to minimize wheels spin as much as possible..

I'd be way to scared to do a redline launch on a bolt on car.. Just because it might **** something up pretty bad.
 
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