what's the proper way to shift?

[450whpGSX]

I have heard that using the brakes to slow down while keeping the car in gear will wear you tranny out. is this true or do you have to put it in neutral then apply the brakes to slow down? what shifting techniques do you guys use when driving?

 

[MrBentley]

My method of shifting is this; whenever im coming to a stop that i know is going to be awhile i put the car in neutral and then brake. The only time i go threw the gears while down shifting is when i think the light might turn green b4 i stop.

As for shifting up. When i see that the light for the other sides are changeing i throw it into first with the clutch in then i rev to about 2k and as the light changes i let the clutch out. after taht i stay in gear till about 4k then i shift.


Questionhow do you guys shift/rev for fast launches/ drag launches and does it require that i "dump" the cutch? BTW what does that mean? Does it mean that instead of a gradual release you let it all the way out really fast?

 

[jaktheripper]

I've always wondered this: double clutching is good on your synchros and clutch, but why double clutch? Is there any difference in dropping it in neutral, revving it then putting it in gear from just revving it with the clutch it before you let off into the lower gear?

 

[Defiant]

I've always wondered this: double clutching is good on your synchros and clutch, but why double clutch? Is there any difference in dropping it in neutral, revving it then putting it in gear from just revving it with the clutch it before you let off into the lower gear?

Yes. That's "rev matching", and it brings the crank up to what will be its relative road speed. But half the guts of the transmission are still at whatevever speed they were at in the higher gear, and the synchros will have to endure the stress of accelerating the layshaft as it brings itself up to the driveline's speed. It will make for a smooth clutch let-out, as the motor's revved up to the road's speed, but it's still quite a lot of work for the synchros. And no they aren't really "built for it". If they were, you wouldn't see thread after thread about 2nd gear grind. Double-clutching engages the crankshaft to the input shaft of the transmission and its constant-mesh layshaft, and the rev will bring the whole gearbox up to the speed of the next lower gear. When matched properly, the shift feels like the cables have come disconnected as the shifter sleeve engages with virtually no resistance. And it's more good for anything than it "wears".

 

[Defiant]

So it is ok to be in fifth gear, apply the brakes to slow down to abot 1700rpm, then match revs and downshift to first whithout any damage done to anything?

There's never a need for first if moving. The motor has enough guts to pull the car from a stop in second, it'll do fine if it's already moving.


As for all the "coasters"- --I just shudder at the thought.

It's becoming a very weird world.

 

[treebonker]

Now you better know how the guy next to you drives during a dsm gathering. :laugh:

 

[MrBentley]

As for all the "coasters"- --I just shudder at the thought.

It's becoming a very weird world.

Well i don't coast but i do go into neutral after second gear when im coming to a stop so im ready for either the light changing or coming to a complete stop. When you do that you can throw it into second or first depending on the situation and the so called "coasting" is minimal.

I don't know if thats how others do it but it sounds like they throw it in neutral when they are still in 3rd and are just starting to slow down.

BTW can you tell me about how to "dump" a clutch or quick launches?

 

[tommiman]

Double-clutching engages the crankshaft to the input shaft of the transmission and its constant-mesh layshaft, and the rev will bring the whole gearbox up to the speed of the next lower gear. When matched properly, the shift feels like the cables have come disconnected as the shifter sleeve engages with virtually no resistance. And it's more good for anything than it "wears".

During double clutching when at neutral should I wait for the RPMs to drop to idle or can I clutch in right away?

 

[Defiant]

During double clutching when at neutral should I wait for the RPMs to drop to idle or can I clutch in right away?

No, the whole idea is to have the crank and transmission turning the same speed they will be when in the lower gear. 4th-cluch in-N-clutch out-rev-clutch in-3rd.

 

[tommiman]

No, the whole idea is to have the crank and transmission turning the same speed they will be when in the lower gear. 4th-cluch in-N-clutch out-rev-clutch in-3rd.

Using your example what I meant was right before doing the "rev" when in neutral is it neccessary to let the engine go back to idle or not?

 

[kyledykstra]

Using your example what I meant was right before doing the "rev" when in neutral is it neccessary to let the engine go back to idle or not?

No, that would defeat the purpose. Typically I only do it when downshifting...

say I'm in 4th gear and I'm coming to a corner where I'll want to be in 2nd gear when I come out of it. So as I'm coming into the corner, I shift out of 4th and let the clutch out. As I'm getting ready to accelerate again, and in neutral with the clutch out, I rev the engine to approximately where it will be when I put the car into 2nd gear, then I put the clutch in, shift into 2nd, and let the clutch out.

If you let the engine go back to idle, you lose any advantage double-clutching gives you. The reason to do it is so the transmission is already spinning at the approximate speed it will be when you place it in gear. (This was the only way I could get my car to downshift into second when I had a crappy transmission)

 

[zxdude]

ok so this is kinda off topic but not really... I've always wondered about RHD cars with 5 speeds.... is the shifting pattern the same...ohh and what about the foot pedals is the far left still the clutch?


Adam

 

[Defiant]

Using your example what I meant was right before doing the "rev" when in neutral is it neccessary to let the engine go back to idle or not?

Oh, I get you. No, use the revs that are already in the crank and just add a few hundred more. You're getting everything up to road speed.

If you ever run across an old enough truck or bit of farm equipment that has a fully non-synchronized gearbox, you may get to try double-clutch upshifting, where you have to slow-down the transmission to get things to upshift cleanly. In that case you'd let the engine come down to idle or so.

 

[Defiant]

ok so this is kinda off topic but not really... I've always wondered about RHD cars with 5 speeds.... is the shifting pattern the same...ohh and what about the foot pedals is the far left still the clutch?


Adam

Interesting question, isn't it? The foot pedals and the shift pattern are the same. However, I've seen in some racer where although RHD, the shifter has been moved to the right, next to the door. And, some single-seat racers have the shifter on the left. I suppose it's mostly a matter of driver's preference at some point in the design, but once it's built, the next driver had better be able to adapt..... and there are also various odd things with the pedals- modern Formula 1 cars with shifter paddles on the steering wheel and automatic clutches have two foot pedals, and braking is done with the left foot.

And there was the Model T....

 

[CowPimp]

I always slow down while remaining in the same gear. When I get to 1000RPMs or so, right before the car starts to rumble a little bit, then I go into neutral to finish off my stop. There's no reason to impose wear on the transmission. New trannies for AWD DSMs cost almost $3K. New aftermarket brake pads can be had on all four wheels for about $200. You decide.

 

[450whpGSX]

why is it bad to downshift to first gear if your rpms in 4th are at about 1200?

 

[kyledykstra]

why is it bad to downshift to first gear if your rpms in 4th are at about 1200?

Why put all that wear on your transmission when there's no need? If you wait until you're stopped to shift into first, it's much easier on your trans. If you're still moving and need to go, 2nd gear works fine.

 

[450whpGSX]

how would that put stress on the tranny if you match revs

 

[tommiman]

Oh, I get you. No, use the revs that are already in the crank and just add a few hundred more. You're getting everything up to road speed.

If you ever run across an old enough truck or bit of farm equipment that has a fully non-synchronized gearbox, you may get to try double-clutch upshifting, where you have to slow-down the transmission to get things to upshift cleanly. In that case you'd let the engine come down to idle or so.

Ok I get the technique now.

I'm also confused. I thought double clutching completely eliminates the use of the syncros. So from your example about the farm equipment the only way not to use the syncros is to get to idle after neutral and right before the rev.

Please clarify this. Thanks.

Also, I'm not sure if it was from this post or another but the trick you posted about bumping 2nd before going to 1st works really well. I probably would've never known that. haha

 

[boostedinaz]

how would that put stress on the tranny if you match revs

Just becasue the motor is at the RPM it should be doesnt mean the parts in the tranny are. The motor may be at 2500 RPM but what does that come out to in 2nd gear or 3rd gear. All those parts inside turn at different RPM and they need to catch up. The synchros do that so thatit shifts without a grind from the mismatched speeds.

 

[kyledykstra]

I'm also confused. I thought double clutching completely eliminates the use of the syncros. So from your example about the farm equipment the only way not to use the syncros is to get to idle after neutral and right before the rev.

Please clarify this. Thanks.

You've got to watch whether he's talking about downshifting or upshifting. When up-shifting (the farm equipment example), you'd double clutch, but you want to slow the transmission down, because you're going from second to third. If you're downshifting, you double-clutch and rev the engine up so it speeds the transmission up, because you're going from third to second.

 

[_Madman_]

And what about starting from 1st, quickly shifting to 2nd & as soon as speed is OK shift to 4th?? That's the way I drive in the city.

 

[kaslasma]

I always thought this was a pretty good post about shifting that was made into a sticky on DSMTalk. A lot of it has been said already but this has it all in one place and explains it so I linked. Hope thats alright.

http://www.dsmtalk.com/forums/showthread.php?threadid=91627

 

[MyEclipse5]

I always slow down while remaining in the same gear. When I get to 1000RPMs or so, right before the car starts to rumble a little bit, then I go into neutral to finish off my stop. There's no reason to impose wear on the transmission. New trannies for AWD DSMs cost almost $3K. New aftermarket brake pads can be had on all four wheels for about $200. You decide.

Where are you buying your trannies. Shep will rebuild yours and add stuff for less than 1k.

 

[JessesTalon]

Also if you look inside your Owners Manual last time I checked it always says to downshift while slowing down to "prevent early trannsmission wear"

 

[VtecRex]

Sence there already has been an example for downshifting... the upshifting way to double-clutch is:

2nd-clutch---Nutral---clutch-3rd.

No need to rev.