Question on launch RPM

Old 12-28-2007, 02:55 PM
  #1  
bigs1975
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Default Question on launch RPM

482BBC,720 lift roller and a hughes powerglide with break,The 2 step has a 4100 chip in it.Does this sound about right for it.I have not ran the car yet but it had these chips in it when I got the car a few weeks ago.
2step has 4100 launch and 8000 rev limit.The shifter switch has a 6200.
Isaw an earlier post and was wondering if I should up the launch to 4500 and shift at a higher rpm and if so what rpm.
I'm very new to electronics and just trying to get an idea of things.I have footbraked for the last 8 years.
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Old 12-28-2007, 06:28 PM
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us7race
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Sounds close. The best way is to play with launch RPM until your 60' is the best, THEN play with the shift RPM until you reach the best ET.
I leave with my sbc at 4600-4800..usually..
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Old 02-26-2008, 07:35 PM
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ML3885
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Default launch rpm

you need to find out what rpm your engine makes its peak torque at and launch at around 200 rpm under that :lol:
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Old 02-26-2008, 10:08 PM
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rob41willys
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Launch chip sounds pretty close but you need to see how the car reacts. I'm assuming with a hughs converter that it is probably stalling at about 5500 rpm, raising or lowering rpm's will change how hard the converter hits. 6200 on the shift seems a little low though. just my thoughts
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Old 03-01-2008, 07:12 PM
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bigs1975
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The convertor is not a Hughes convertor.Not sure what brand but I was told its a 5600 5800.I'm going to buy some more chips and go play in a week or 2.
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Old 03-03-2008, 05:14 PM
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bjuice
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iregardless of what rpm the converter is advertised..its gonna vary with different motor's, cam profiles etc..in order to properly place the launch chip you must find where the converter flashes ( actual flash)..it will flash more off the tranbreak..so i would recommned checking the flash point off the tranny break instead of foot break...
when you find your flash point then you want to place your chip anywhere from 1,000 to 800 rpm back from this point...this will give you the hardest launch and quickest 60 ft time...

if you leave past your flash point the car will slow down on the 60 ft..It will LOSE THAT SLING SHOT FEELING...

Brian
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