best rpm to shift

Road race, Auto X, or the Drag Strip

best rpm to shift

Postby bradc » Wed Jun 15, 2005 1:49 am

pretty self explanitory, what rpm do you guys shift at when you drag? I'm shifting at 6800.
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Postby EVcelica » Thu Jun 16, 2005 6:26 am

It all depends on the ratio of the gears to each other, from 1 to 2, from 2 to 3, ect. Usually you take 1st up as high as you have balls enough to do, 7300? :shrug:. and work your way down from there. You could get a dyno on your can and then do a little math with each gear ratio to find out the EXACT shift point to shift at for each gear, thats if your completly anal. but once I get my car dynoed, I'm doing this for sure.
Anyways I like shifting around 7000 in first, 6900 in second, 6700 in third, and 6500 in forth.
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Postby bradc » Fri Jun 17, 2005 4:28 pm

Once I replace my blown turbo I'd love to get the car dynoed but I can't seem to find an AWD dyno in san diego. Anybody in the area know of one?
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Postby RacerJim » Fri Jun 17, 2005 8:56 pm

EVcelica wrote:It all depends on the ratio of the gears to each other, from 1 to 2, from 2 to 3, ect. Usually you take 1st up as high as you have balls enough to do, 7300? :shrug:. and work your way down from there. You could get a dyno on your can and then do a little math with each gear ratio to find out the EXACT shift point to shift at for each gear, thats if your completly anal. but once I get my car dynoed, I'm doing this for sure.
Anyways I like shifting around 7000 in first, 6900 in second, 6700 in third, and 6500 in forth.


You are of course correct...it all depends on the ratios of the transmission gears relative to each other and, therefore, the RPM difference when shifting from one gear to another (up or down).

In any event, it's not completely anal to produce a Gear & Speed Chart which will show what RPM the engine will be at when shifting from one gear to another, up or down, at a given road speed. All you need are the transmission gear-ratios, the differential gear-ratio, tire circumference (measured), a few mathmatical formulas, some graph paper (preferably 8.5"x14"), a straight edge, a pencil and about an hour's time.
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Postby bradc » Sat Jun 18, 2005 12:33 am

Oh please fill me in almighty guru's of shifting. :notworthy: Is there a break down of all this anywhere? See this is why I ask simply questions cause you'd be amazed at the complex answers you get to learn from.
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awd dyno

Postby Guest » Mon Jun 20, 2005 7:00 am

pann auto has one in diego.

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