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MrJester
04-21-2007, 06:02 PM
Okay so this is my first MT car and I am trying to get better at driving it and what not and I would like to know what the difference of RPMs is between the gears at a constant speed. Thanks guys.

Edd
04-22-2007, 09:44 PM
You need to determine it with your own car. Eg, if you shift at 3k RPM from 1st to 2nd, and your RPM drops to 1.5k [unmatched], then to rev match, 1.5k is the point you need to let the revs drop to in neutral before putting the car into 2nd.
Or, say you downshift from 3rd to 2nd and the revs change from 1k to 2k. That suggests that in order to match revs you need to blip the throttle [in neutral* or with clutch depressed**] to bring the revs up to about 2k before you engage into 2nd.

*By clutching in and putting the car in neutral (then re-engaging the clutch), the transmission is rev matched (double declutching).
**By rev matching with the clutch disengaged and remaining in gear, only the clutch plates will be in sync - allowing you to release the clutch more quickly, but it will not reduce wear on syncros.

I hope that makes enough sense, still getting the basics down myself before I start trying it.

Pars
04-22-2007, 11:44 PM
Okay so this is my first MT car and I am trying to get better at driving it and what not and I would like to know what the difference of RPMs is between the gears at a constant speed. Thanks guys.

I couldn't say exactly, but it's about 1000rpm per gear. So, if you're doing about 40mph in fifth and want to drop it into 2nd gear, just punch/blip the gas hard enough so that the rpm climbs 3X1000rpm (3000rpm) before popping into 2nd. I used to be more precise with my old 98 Civic when rev-matching, but with the tiny delay in the Yaris's accelerator pedal, it's tough to be spot on.

Edd
04-23-2007, 12:44 AM
Remember it's a multiple, not an addition/subtraction. So the revs may drop 1500 if you upshift at 3000, but if you upshift at 6000, they would drop 3000.

That's why I said it's easiest just to shift WITHOUT rev matching, and see where the revs drop to in each gear. Once you have an idea of that, you know where your target revs are.