what rpm to leave at while footbraking

Old 08-11-2009, 04:58 PM
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JEFF69Z28
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Default what rpm to leave at while footbraking

should i leave at idle or brinhg up the rpm's,8 inch converter 4500 stall,4.56 ring&pinion,600 horse motor,86 monye carlo.
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Old 08-11-2009, 05:29 PM
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Drtmod5
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Most converter makers will say launch @ 800-900 less than stall speed for best results. You need to bring rpm up, but don't know how much your brakes will hold before it pushes you through the lights. When I footbraked, my converter was @ 3500, but could only leave @ 2000-2200 before it pushed.
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Old 08-11-2009, 08:48 PM
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mopar1968
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I footbrake at 2000 rpm's, my convertor is a 4800, leaves pretty hard :!:



''JUST MY TWO CENT'S WORTH''
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Old 08-11-2009, 09:38 PM
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ashbros
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Depends on how well your brake system holds under pressure.

If you have drum brakes I doubt you will be able to stall as high as if you hard 12-14 inch front disc brakes.

Better get out on the pavement and experiment.

Let us know what you come up with.
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Old 08-11-2009, 10:34 PM
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Tod74
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You will get more suspension travel if you are closer to idle I think....wouldn't ya? Iduno.
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Old 08-11-2009, 11:02 PM
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cepx111
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I just ease up on it till I load the car up, suspension, drivetrian etc - usually somwhere around 2K rpm, if I flash it just off idle, my reactions times suffer.

CP
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Old 08-12-2009, 01:50 PM
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CamBirdRacing
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I leave about 2000 on a 4500 stall. That's about all my brakes will hold.
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Old 08-13-2009, 04:03 PM
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TheEngineer
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I've had several different race car combinations and every package was completely different on the launch RPM.

For example; my stroker big cube Camaro works best if I allow the converter to flash off the line. With this car I just load-up the drive train at about 1800 RPM and allow it to flash-up to 5200. If I try to lauch with more RPM, the 60 fts slow down. Less is more on the launch!

My tube chassis car w/ trans-brake is completely different. The more RPM I can stall it on the line, the faster it goes. I also foot-brake this car and more RPM is better. Additionally, more consistent ETs and better reaction times with the higher launch RPM with this car.

Therefore, you should TnT a lot and try many different RPM launches to determine what works best with your car.

Warren
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Old 08-14-2009, 10:34 AM
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FullTimeRacing
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I leave at 2500 RPM anymore I red light . If your car can leave at idle it will be best for consistency. jmo
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