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Discussion Starter · #1 ·
I was wondering what RPMs anyone has been having luck launching at. I know the tires suck, and i tend to release the clutch slow (im used to my nova where they just spin all day), but I was curious on what you guys have been having luck with ?

Thanks
 

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It's not very fair for me to answer this. I have Toyo T1S 245/40/17s on 8.5" rims. It's hard to break them loose unless there is paint on the pavement. I can launch at 4k without too much drama. The OEM tires won't hardly even take 2200. They really suck.
 

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What about lowering the tire pressure lobux on our OEM's while they DO have tread to help with launching? Think it would help at all? What psi?
 

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Discussion Starter · #4 ·
I'm not lobux, but I would be cautious about lowering pressure too much. We dont exactly get race rims with the car and I would imagine that you could pop a bead off if you are too rough on it.
 

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Originally posted by OliverThomas@Jun 23 2005, 05:31 PM
What about lowering the tire pressure lobux on our OEM's while they DO have tread to help with launching? Think it would help at all? What psi?
You can only go so low before the tread cups in the middle and you are back to losing surface area again. There's not a lot you can do with the OEM tires, they're just too slippery. Personally, I would not go below 22 psi.
 

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I'd be afraid of losing a tire doing that. With the oem tires it's not even worth it.
 

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Ok yes i know i have the oem tires and yes they suck @ss i hate them. but if you want a good launch and not spin to much this sounds crapy but do not go above 1500 RPMs thats what i launch at some times but on the track i launch well at idol haha cause the tires will jst spin and spin and spin. If you want to lower ur tire pressure read the dorr jam thats how you tell how low you can go. Radial tirea have max surface area at alomst full PSI well what the spec is anyways. but if you go to low the tire becomes convex in the middle and ull be riding on the very out side of the tire wich is very bad for radials or any tire. so your best bet is to save up and get some kick ass tires so you can race alot better. Well thats my info so i thought i would let you know.
 

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Well I have the oe rubber and I don't mind them at all. I'm not racing around town all day long, but I can launch the thing like a mother, and I bet I'd be just as fast in my stock tc with oe rubber as anyone else's stock with aftermarket rubber. Its not a drag car, theres really not much the increased traction is gonna do for you, unless you're powersliding around dangerous mountain curves at 60mph. I have no problem chirping my rubber and sliding around city corners fast enough to scare the #### out of other drivers and pedestrians alike. The potenza's are fine for me, for now, I've got 15k on them.
 

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Bullshit. I can drop the clutch at 4 grand without wheelspin. The OE tires couldn't do that on fully prepped surface with a full burnout. The OE tires SUCK. Period.
 

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i got my 5-speed black sand pearl tc with yokohamas stock. i don't know how much better these tires are compared to the bridgestones or even if they are better than the bridgestones, but i launch at 2, 5000 with no problem, chirp from 1st to 2nd and from 2nd to 3rd.
 

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Originally posted by iRoq@Jul 28 2005, 03:45 PM
the car has plenty of torque to make that possible, and the tires are great. if you can't make that happen, brush up on your quick shifts?
Um no. If you ever chirp, you are displaying poor engine control. You should never chirp gears. It's a clear indication you've failed to match engine speed and road speed correctly. Shifting should be completely seemless and difficult to notice in a well driven car. Ever see a Top Fueler chirp? Funny Car? Pro Street? Why??? Because YOU LOSE TIME. I surely don't need to practice abusing my clutch and tires in this way, I shift very quickly without any drama. The only time I chirp is when crossing pavement markings under launch power. It should never happen on a shift.
 

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I agree that you have to be skilled not to chirp your tires at all. It takes a great deal of experience on your trani and motor to feel that out.

But it has nothing to do with horse power or torque chirping you tires in a manuel car.
My friend has a 02 honda civic, which is rated at 115hp. he can do a little more than a chirp from 2nd to 3rd.

Now if your driving an automatic it takes a little more HP and torque and a shift kit to get them to chirp from 2nd to 3rd.
 

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Every site has it's guru's...on the short time I've been on this site I've quickly learned that lo bux racer is one of them on this site. Everytime I see a post from him I read it, because it usually has some good info in it.

This time I have to correct him though :) Top Fuelers and Funny Cars don't chirp gears because they don't have any transmissions...clutch pack to drive shaft to differential. Pro Stockers have so much tire and they have gotten the suspension technology down pat. They rarely break the tires loose despite full throttle shifting with Lenco trannies (can be shifted without depressing the clutch - clutch is only used off the line).

Also on slippery street tires a LITTLE tire spin will most likely net you the best 60 foot times, which equal quicker 1/8 or 1/4 ETs. Why? Because reving up into the meat of the power band just causes massive wheel spin and launching at a low enough rpm to not spin the tires usually causes a bog off the line. Now if you have EddieMoneys' 690hp/675lb-ft Corvette, bogging isn't a problem...but drag racing with street tires and an engine like that would be an exercise in futility :)

The other option is to rev higher and to slip the clutch off the line to control wheel spin...while that may give you the best launch, it's not going to work for long...a clutch change will be in your near future.
 

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Point well made. When I was a kid in the 60's and 70's Top Fuel and Funny car used a two speed gearbox. They make a lot more power now than they did back then, and they've figured out how to get it to the ground better. They still never "chirped." More often than not, they went into the wall if something like that happened because it only rarely breaks on both sides equally. They have come a LONG way...

I totally agree with the clutch assessment, but that's pretty typical for any OEM clutch forced into drag racing use. The only exceptions I've seen to that are bikes with wet clutches. They seem to take a lot more abuse in OEM trim, and typically just need stronger springs to be considered heavy duty.

I doubt the tC clutch will take much abuse at all. It's not very big, and it isn't meant to be slipped without mercy.
 
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