Rpms not dropping fast enough when speed shifting

[Higgs Boson]

Only partially agree, b/c of majority of the modern cars made these days.

But fast shifting and rpm matching are not mutually exclusive by definition.

By a tune, the rev hang can be cured (see my post above, with a link to another post). Additionally, one can make the flywheel lighter. This way (e.g., the flywheel having the right weight), you can shift fast while the rpm will still match.

100% incorrect.

Also, rev hang in the tune has 0.00 to do with shifting even remotely quickly.
Rpms fall when the clutch comes out and the next gear is in place.

Again, if we are talking about normal shifting, yes ok, smooth and slow makes the next gear engage better. If we are talking about speed/power/fast shifting, then no to all of it.

See the video posted above by dev.....that is speed shifting. Where is the rev hang? How can one expect rpm to drop at all?

Sponsored

 

[Blake5]

All I am asking is why shifting fast from 1st to 2nd the rpms hang longer than they should. No other gear does it. I am not shifting slow and I don't have my timing off. People have responded and stated there is a rpm hang in the stock tune, and that's what I figured. I'm not going to sit here and argue with someone that wants to sit here and say it's driver error/slow shifting. I have my answer and hopefully my tune coming this week will fix it. Thank you to those who responded

 

[dev1360]

The Rev hang in the tune only happens when you shift really, really slow. It doesn't happen when you're WOT shifting quickly.

You're going to be disappointed when your tune changes nothing about what you're describing.

 

[Todd15Fastback]

All I am asking is why shifting fast from 1st to 2nd the rpms hang longer than they should. No other gear does it. I am not shifting slow and I don't have my timing off. People have responded and stated there is a rpm hang in the stock tune, and that's what I figured. I'm not going to sit here and argue with a dumbfuck that want to sit here and say it's driver error/slow shifting. I have my answer and hopefully my tune coming this week will fix it. Aside from the one dickhead thank you to those who responded

Higgs does his own tuning and has a ton of really good info he has shared across many a thread. I believe he is also a pretty successful drag racer that has campaigned a few cars. Just sharing what I have read him post him. Never meet him, ever.

 

[Horse]

100% incorrect.

Also, rev hang in the tune has 0.00 to do with shifting even remotely quickly.
Rpms fall when the clutch comes out and the next gear is in place.

Again, if we are talking about normal shifting, yes ok, smooth and slow makes the next gear engage better. If we are talking about speed/power/fast shifting, then no to all of it.

See the video posted above by dev.....that is speed shifting. Where is the rev hang? How can one expect rpm to drop at all?

Maybe it's all about disagreement on usage of fast shifting?

To me, fast shifting is just `shifting fast', still lifting gas. The no-lift shift is power shifting as far as I know.

The stock tune keeps the rpm hanging, thus making smooth fast shifting impossible. Also, even when the rpm does start to drop, it drops slow (due to the weight of flywheel maybe). This was why I said that, with a tune to eliminate rev hang and with lighter flywheel, one can shift fast (and lifting gas) while still making the rpm match (hence smooth).

 

[Blake5]

The Rev hang in the tune only happens when you shift really, really slow. It doesn't happen when you're WOT shifting quickly.

You're going to be disappointed when your tune changes nothing about what you're describing.

It happens almost every time I shift at WOT from 1st to 2nd.. are you talking about the rev hang for the next gear? Yeah I get its supposed to do that.. But I'm talking about when I shift fast the rpms hadn't dropped fast enough and make the shift really jerky. Is that normal? I've driven a manual car a lot but this is the first one I've daily driven.

 

[dev1360]

I have no issues WOT shifting this car. There's a lot more ECU intervention fuckery than my C6, which waters down the experience for me. But I don't have any problems or notice any jerkiness. I posted the video above of me WOT shifting with all stock stuff.

 

[Horse]

Yes, S550 has a second stage of rev hang where the ECU keep the rpm at (about) the right value for the next gear. To miss this window of opportunity, you must be super slow.

But the OP is talking about the rev hang in which the rpm hangs at the rpm value as of before you step on the clutch. If you are fast enough, this (first stage) rev hang will become annoying.

 

[Blake5]

Yes, S550 has a second stage of rev hang where the ECU keep the rpm at (about) the right value for the next gear. To miss this window of opportunity, you must be super slow.

But the OP is talking about the rev hang in which the rpm hangs at the rpm value as of before you step on the clutch. If you are fast enough, this (first stage) rev hang will become annoying.

THANK YOU

 

[Higgs Boson]

Maybe it's all about disagreement on usage of fast shifting?

To me, fast shifting is just `shifting fast', still lifting gas. The no-lift shift is power shifting as far as I know.

The stock tune keeps the rpm hanging, thus making smooth fast shifting impossible. Also, even when the rpm does start to drop, it drops slow (due to the weight of flywheel maybe). This was why I said that, with a tune to eliminate rev hang and with lighter flywheel, one can shift fast (and lifting gas) while still making the rpm match (hence smooth).

I agree it is 100% a discrepancy in what speed shifting really is. When you are shifting fast, the idea is to have the clutch in for as short a time as possible. There is no rev hang because a fast pedal release engages the next gear and the motor drags the rpms down. If you are waiting at all for the car to do something then you are waiting far too long.

The rpms drop slow during normal "gas off" events because the throttle blade does not shut all the way or quickly like a cable actuated throttle. This makes no difference in a speed shift....I don't even let off the gas anyways.

Otherwise it's a normal shift and you have to slip the clutch at least a tiny bit to smoothly couple the clutch and pressure plate.

when I shift fast the rpms hadn't dropped fast enough and make the shift really jerky. Is that normal? I've driven a manual car a lot but this is the first one I've daily driven.

Now we are getting somewhere. New to manual shifting. Nothing to be ashamed of, we all had to start somewhere, but a more humble approach would do you a lot of good.....

 

[Higgs Boson]

I've seen multiple of your responses to other threads and you're just a conceited asshole in almost all of them therefore I don't care for your response. I know it's not driver error as I've driven other manuals that don't have this problem. Thanks for your input buts it's not wanted or needed

:first:

Forgot your meds or just cranky?

 

[dev1360]

But the OP is talking about the rev hang in which the rpm hangs at the rpm value as of before you step on the clutch. If you are fast enough, this (first stage) rev hang will become annoying.

I've never once felt this in the car. And I'd be willing to bet it isn't real.

 

[Blake5]

Now we are getting somewhere. New to manual shifting. Nothing to be ashamed of, we all had to start somewhere, but a more humble approach would do you a lot of good.....

Because I know if I said it originally I'd have people like you saying its driver error when I know it's not. I know how to shift slow even with the 2nd stage rev hang for the next gear, but I'm talking about when I shift fast

 

[Horse]

I have no issues WOT shifting this car. There's a lot more ECU intervention fuckery than my C6, which waters down the experience for me. But I don't have any problems or notice any jerkiness. I posted the video above of me WOT shifting with all stock stuff.

No offense intended, but when you do as you describe, is it all smooth (as in rpm-perfectly-matching smooth)? Most Mustang drivers don't care about smoothness; they just dump the clutch and enjoy the impact of fast engine rpm to the transmission.

 

[dev1360]

No offense intended, but when you do as you describe, is it all smooth (as in rpm-perfectly-matching smooth)? Most Mustang drivers don't care about smoothness; they just dump the clutch and enjoy the impact of fast engine rpm to the transmission.

If you're trying to smoothly match your RPMs during a "fast shift" then it isn't fast.

Sponsored