Nissan 370Z Forum - SynchroRev & layshaft

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SynchroRev & layshaft

Just stumbled upon this forum as I was looking for some info on my new 370z. There's a lot of great info I've read so far.

I had a question about the SynchroRev feature on my Z. Ever since I learned to drive a manual, I've been double-clutching. I was told this was beneficial (but optional with modern trannies) for two reasons, 1) rev-matching for smoother clutch engagement but more importantly 2) Speeding up the layshaft for reduced wear on the synchros when aggressively down-shifting.

I had an older Nissan and they were known for using cheapie brass synchros that wore out quickly.

Does the SynchroRev feature of the Z also speed up the layshaft on downshifts?

Quote:

Originally Posted by taejoon (Post 63965)

I don't believe it does, at least from what I understand of it. Double-clutching will still have the same benefits and drawbacks on the 370Z as it does any other modern car (smoother engagement in corners, but more clutch wear per shift). I never did see anything that definitively lead me to believe double-clutching reduces synchro wear on modern cars though.

With SRM enabled, double-clutching will be even easier than it is on other cars.

Quote:

Originally Posted by wstar (Post 63990)

How do you or why would you double clutch with syncrorev enabled?

Oh and thought this was the same thread, but here's my response on the topic from the other forum:

Quote:

Originally Posted by Sensi09

With modern synchros, there's no need to double clutch, so in terms of wear, there should be no appreciable difference.

With that said, I do enjoy double clutching in certain gears, especially into 2nd gear. Just as fast as a regular rev-match downshift IMO and tends to be consistently smoother for myself as it "flows" a little more. Generally I'll double clutch when moving down multiple gears or going into a low gear.

Quote:

Originally Posted by sensi09 (Post 64862)

How do you or why would you double clutch with syncrorev enabled?

Same as any other car really, except the rev-matching is done for you. I assume SRM picks up your destination gear as you arrive at the start of the gate, before engagement. My Z is 7AT, so I'm only guessing :).

So clutch in, pull out of the previous gear, move to the gate entrance of the next gear to clue in SRM (which will revmatch at this point), drop the clutch and put it in again to spin up the layshaft, then drop the stick all the way into gear and engage for real.

No really... there is 0 help from double clutching... you will just wear out your throwout bearing sooner

Quote:

Originally Posted by shabarivas (Post 65023)

No really... there is 0 help from double clutching... you will just wear out your throwout bearing sooner

I could feel the difference on my last car, it definitely has an effect. That was a GM T-56 6-speed manual, from a 1999 car. Even if you match revs perfectly, there's a slight jerk in your traction when engaging the new gear on a downshift, which is more noticeable if you're shifting through a curve (as you're already near traction limits). The double-clutch makes it a little bit smoother.

When im in the Z or even my G35 (05 6mt)... I NEVER double clutched and revmatched PERFECTLY ... the Z is especially smooth... there are 0 jerks i promise you... well a few around the forums :p but 0 in the shifting :)