Downshifting 2 gears - technique
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From: San Fran
Originally Posted by jyeung528,Apr 4 2007, 02:49 PM
if your clutch is not engaged...you can speed up or slow down the layshaft by going into different gears.
if your gear is in neutral, you can speed up or slow down the layshaft by engaging the clutch and matching it to the engine speed.
if your clutch is engaged and you are in a gear...you layshaft is matched to your engine speed and will ultimately spin the drive shaft (or vice versa on a downshift)
if your gear is in neutral, you can speed up or slow down the layshaft by engaging the clutch and matching it to the engine speed.
if your clutch is engaged and you are in a gear...you layshaft is matched to your engine speed and will ultimately spin the drive shaft (or vice versa on a downshift)
I row through each gear, (4th to 2nd, i row through 3rd)...BUT i don't engage the clutch...the clutch pedal is pushed in through the rowing down the gears...i rev-match before engaging the clutch in 2nd.
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From: Temple City
Originally Posted by pantyraider,Apr 4 2007, 03:03 PM
Doesn't make any sense. The layshaft spins from power from the engine, how does changing gears effect the speed of the layshaft when it's not under power from the engine, and more importantly why bother ? You said you "rev-match" :
How is your "rev matching" doing anything if you don't let out the clutch? Your method makes no sense.
How is your "rev matching" doing anything if you don't let out the clutch? Your method makes no sense.
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From: Temple City
Originally Posted by pantyraider,Apr 4 2007, 03:03 PM
(edit) Ok, I get how the layshaft could speed up or down when you engage gears, but still don't understand why you would care. You said you "rev-match" :
How is your "rev matching" doing anything if you don't let out the clutch? Your method makes no sense.
How is your "rev matching" doing anything if you don't let out the clutch? Your method makes no sense.
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From: Santa Cruz, CA, US
Originally Posted by mikegarrison,Apr 4 2007, 02:30 PM
I guess I will elaborate -- I've tried it all those different ways, and I screw up least often when I engage each gear. So that's the way I do it. It has nothing to do with the car, and everything to do with the driver.
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From: Santa Cruz, CA, US
Originally Posted by tinkfist,Apr 4 2007, 02:55 PM
I personally go straight to the gear I want and I'll do it as late as possible into braking to avoid any early engagement overrevs 
What happens if the car gets sideways and you need to get the tail undercontrol. You either have no torque in 4th gear as you're at 2k rpms or you're in neutral.
Either way you're in for trouble imo if something unexpected happens.
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From: Santa Cruz, CA, US
Originally Posted by jyeung528,Apr 4 2007, 03:15 PM
i do it so the synchros don't have to do more work in a 4-2 shift. it is less work on the synchros to do a 4-3-2.
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From: Vegas Baby, Vegas
Originally Posted by krazik,Apr 4 2007, 04:31 PM
revmatching makes the synchros do less work. If you're diving into a brake zone with the car in neutral the whole way, please stay away from me on the track. You've got no control over your car.
If maintaining control of the car isn't enough reason to be IN a gear, another valid reason is to develop muscle memory. I don't want to waste "cpu" cycles on downshifting differently for a 2nd gear turn or a 3rd gear turn. If I'm in 4th and going to 2nd, I go through 3rd to get there each and every time. Every downshift on every turn on every track is the same, even those I've never seen before. It's one less thing to worry about. This way I concentrate on putting the car where it needs to be and the shifting is by rote.
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From: Encinitas (San Diego), CA
I generally row through tthe gears and lift clutch in each gear, but there is one corner that I seem to recall I sometimes (or always? memory is getting poor with age) row through without engaging the clutch, and that's turning into the infield at Cal Speedway, where you are going from 135 on the oval in 6th, and quickly going down to 3rd or 2nd, and there isn't enough time to engage the clutch in each, especially if you are dive bombing for a pass.
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From: Farmingdale, NJ
Originally Posted by krazik,Apr 4 2007, 07:29 PM
You coast into your brake zones or do you stay in 4th and bog it?
What happens if the car gets sideways and you need to get the tail undercontrol. You either have no torque in 4th gear as you're at 2k rpms or you're in neutral.
Either way you're in for trouble imo if something unexpected happens.
What happens if the car gets sideways and you need to get the tail undercontrol. You either have no torque in 4th gear as you're at 2k rpms or you're in neutral.
Either way you're in for trouble imo if something unexpected happens.
I like Ludedude theory of having every downshift pattern be the same
