CP

Hi,

I understand the reasons behind blipping throttle on downshifts, so engine speed and wheel speeds are a better match going to a lower gear. That would make for more smooth clutch engagements.

My question is: do you match the revs precisely, or within 500-1,000 RPM of the exact rev? Confession: I am not sufficiently skilled to match revs exactly. I just get close enough for government work and call it good.

Thanks for the education.

CP

Tom W

Exactly, no. Close enough so the wheels don't chirp and upset the car (the reason for doing it) is good enough.

TrackJunke

As precisely as you can. I find rev matching is something that you cant "think" about too much or else you overthink it. Once you learn the technique, trust yourself and have confidence that you will do it correctly. On a side note, IMO I think it is better to be slightly above your desired target than slightly below as it will upset the car less.

Flying Finn

Not exactly but closer than 500 rpm. Like Tom said, as long as when you release the clutch, and everything stays smooth, you're good.

Mark in Baltimore

What everyone else said. CP, you'll know when you've got it right, for the gear will drop into place and the tach needle won't move a bit when you let out the clutch. If the tach needle bobs up or down, then you were off in your rev matching.

InTheAir

I can usually match the RPMs to within about 200 by blipping on a downshift, which results in a smooth and mostly imperceptible shift. I do it by knowing the difference in RPM between each of the gears given the same speed. Most of the downshifts (6-5, 5-4, 4-3) are about 800 RPM difference at the speeds I'm typically downshifting at, so I blip up to +800 RPM. The tricking downshift is the 3-2 which is about 1200 RPM difference.

Because of the nature of ratios, these differences vary a bit with speed, but it works reasonably well. The only downshift blip that takes a bit more attention is the 3-2, which can be 900 to about 1300'ish, depending on speed.

*The are general numbers. Refer to the gear chart for specifics.

Arrwin

Sounds all too familiar.

Great thread!

Dr. No

Goal: as closely as possible.
Reality: +/- enough to make me say "that was a crummy shift" more often than I'd like.
Thank Porsche for synchromesh.

leosayer

I agree with Tom, as long as you manage to keep things smooth then that's all that matters.

To do that takes lots of practice and lots of concentration until it becomes intuitive. You end up doing it by feel and by listening, not by looking at the speedo and rev counter.

Tom W

I can't believe anyone actually has the time (or would take the time) to check the tach during a race or even a DE event - you should have your eyes up and be looking for the apex and track out points, not on the tach. Do it by sound/feel and you will get better with practice. If it feels smooth, you did it right. If the tires chirp, you need to practice more - what a shame!

tlark

[QUOTE=Tom W]I can't believe anyone actually has the time (or would take the time) to check the tach during a race or even a DE event - you should have your eyes up and be looking for the apex and track out points, not on the tach.

That about sums it up, well put.

Can you find a way to incorporate that statement to cell phone users behind the wheel on public roads.