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Old Dec 9, 2007 | 12:01 AM
  #1  
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lauching

where do u guys leave your RPM's at when you race from a stop. I've been using 2.5-3 but its not that great
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Old Dec 9, 2007 | 12:34 AM
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4k
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Old Dec 9, 2007 | 12:47 AM
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my best result at the track was at 6-7 and ease off the clutch quicky but dont drop it
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Old Dec 9, 2007 | 12:51 AM
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4.5 to 5k rpm. feather the clutch quickly..

beers
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Old Dec 9, 2007 | 12:53 AM
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Depends on the amount of wheel spin you can get out of your tires. I just tested 60 launches in a formula mazda with sticky tires and I HAD to launch at 8000 to make sure all the valves were open to get wheel spin instead of bogging the engine.

Your best bet is to find out what launch RPM will leave you at 6000 when the tires hook up. Under that you have to deal with the vacuum valves and APV valve being confused or closed when you need the power.
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Old Dec 9, 2007 | 12:57 AM
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^ you lucky SOB!!
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Old Dec 9, 2007 | 01:05 AM
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a

Originally Posted by rotormech
Depends on the amount of wheel spin you can get out of your tires. I just tested 60 launches in a formula mazda with sticky tires and I HAD to launch at 8000 to make sure all the valves were open to get wheel spin instead of bogging the engine.

Your best bet is to find out what launch RPM will leave you at 6000 when the tires hook up. Under that you have to deal with the vacuum valves and APV valve being confused or closed when you need the power.

And remember...that is in a 1200lb car. With the stock rx8 (3000lb) you need all the r's you can get. Rotary engines don;t make piston style torque.....so spin that bitch up to the powerband.
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Old Dec 9, 2007 | 01:08 AM
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well peak torque is at 5500 stock, so i think that would be the best place. i just do it at 4
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Old Dec 9, 2007 | 01:17 AM
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Originally Posted by chetrickerman
well peak torque is at 5500 stock, so i think that would be the best place. i just do it at 4
As long as you are around 5k when the tires hook. Don't concentrate on lauch rpm but how far it falls when you let loose. Believe me.... I had a mechanic leave one of the vacuum lines off and the car feels like a dog until the APV hits and then the girl runs like a raped ape. On our car the APV hits at 7200...so that would be a key thing to find out (when the APV opens).
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Old Dec 9, 2007 | 01:24 AM
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correct. thats why when you let out the clutch, you push in the gas the same amount
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Old Dec 9, 2007 | 01:30 AM
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Originally Posted by chetrickerman
correct. thats why when you let out the clutch, you push in the gas the same amount
My bad...I havn't had a clutch without any feel for awhile. More like a light switch, so I've had to use the tire rubber as the clutch. I'm gonna have to steal the keys to the rx8 and go try some things. What tires do you run....brand and width?
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Old Dec 9, 2007 | 01:33 AM
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i can imagine that. you are a lucky guy
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Old Dec 9, 2007 | 08:39 PM
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i usually do it at about 4k or a little above but ive only really done launched like that on the dyno with a 1/4 mile simulator. I would imagine tires,wheels,clutch, conditions all have a big play in the results...
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Old Dec 9, 2007 | 08:51 PM
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especially if you have an unsprung clutch like he was using.

but i just like 4k. the pull is pretty damn good. and its not too harsh on the clutch
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Old Dec 9, 2007 | 08:58 PM
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4-5
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Old Dec 10, 2007 | 12:02 AM
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Originally Posted by rotormech
Depends on the amount of wheel spin you can get out of your tires. I just tested 60 launches in a formula mazda with sticky tires and I HAD to launch at 8000 to make sure all the valves were open to get wheel spin instead of bogging the engine.

Your best bet is to find out what launch RPM will leave you at 6000 when the tires hook up. Under that you have to deal with the vacuum valves and APV valve being confused or closed when you need the power.

= lots of wheel hop..

beers
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Old Dec 10, 2007 | 08:46 AM
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Originally Posted by chetrickerman
especially if you have an unsprung clutch like he was using.

but i just like 4k. the pull is pretty damn good. and its not too harsh on the clutch
On the factory RE040 tires, 4K seems just about right. The rear tires spin briefly, hook up and you take off w/o a bunch of wheel hop.

When autocrossing on r-comps, I've been told that a good launch will be in the 5-6K rpm range depending on surface. This is supposed to have a similar result - little wheelspin w/o almost no axle hop.

Even if your engine is in the fattest part of its powerband, if the rear tires are spinning, you're just making noise and going no where in a hurry.
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Old Dec 10, 2007 | 09:51 AM
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I side step the clitch and then bounce on the rev limiter...

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Old Dec 10, 2007 | 09:54 AM
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you would
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Old Dec 13, 2007 | 05:49 AM
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+1 on around 4k or a lil bove on stock 18s.
enough wheelspin and enough space to slightly let off until the car's catching up on traction to then refloor it. not much of gas modulating needed around that rpm.
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