I have an 07, bought brand new, also learned manual on it. So it has as many mileages as I have experience driving a manual. It's been a little over 3.5 years now and I've got 86,000km.

For the longest while, I've been feeling like the rev drop between 1st and 2nd at redline is too slow. In a sense, I often have to wait for the revs to drop before I let the clutch out in order to get a smooth 1 -> 2 shift while trying to go fast. It seems like time is lost due to this waiting for smoothness.

I don't want to shock the transmission by just dumping it. I find that with more experience, I am now shifting faster than the revs are dropping in the next gear.

Is this a sign that I need a lighter flywheel? Or am I missing technique here that I don't know?

 

https://www.rx8club.com/rx-8-discussion-3/rev-match-downshifting-217195/
Check here.

 

That thread is about downshifting. I am upshifting.

 

Ah, I see. Keeping the rpms up while upshifting will help with initial torque (which the 8s typically suffer from a lack of). When upshifting, disengage the clutch (fully depress clutch pedal), shift to the next highest gear, smoothly disengage the clutch 3/4 of the way... hold there briefly until you feel the plates grab then fully release the clutch pedal. Just takes practice and knowing what to feel for. When done properly, the whole process is smooth and effortless with no jerking of the car.

Hope this helps.

 

I don't think you understand my original post, but thanks anyways.

 

A redline 1st to 2nd shift results in a 3500 RPM drop. Its not uncommon to have the drivetrain bring down the engine speed and give the car a little jerk or spining of the tires. No real harm done. It is possible you are releasing the gas pedel a little late, causing the RPM's to stay higher, longer. Or your hitting the gas pedel a little early. Either of those give the car that surge or Jerk feel but neither are really doing any harm if it only happens once in a while. On the other hand, if you drag racing from light to light everyday, your going to shorten the life of your clutch, motor mounts and trans/diff (maybe).

 

It is this 3500 rpm drop that I find too slow as I'm already in 2nd gear and waiting for the rev to drop so it will be a smooth shift.

 

Sounds like a slipping clutch.

Drive slow in 4th gear (below ~2500rpm) Punch the throttle. If the car just kinda lugs and gradually increases spead, you're good. If it seems to rev but not go anywhere, it's time for a new clutch.

 

If your going WOT and redlining in 1st gear, smooth shouldnt be a big concern. You can feather the clutch to make it smoother.

 

Because your shifting technique is now smoother and quicker (which usually go hand-in-hand, btw) you are one of those few people whose technique can benefit from a lighter flywheel (the converse is more typical). Having had one on my car since a few months after I bought it new in late 2003, I can drive and shift as smooth as glass while reducing my shifting time to 1/2 of what it used to be.

Additionally, having a lightweight flywheel makes downshift rev-matching easier as all it takes is a blip of the gas pedal to find the RPM you are seeking to match the synchros. Again, I am smooth as glass when doing this and I am sure you will see the same results with the same enjoyment, Footman.

 

Your missing the point of his question. His complaint is that when he redlines the car in 1st and goes to shift to 2nd, the Engine RPM is too high for a smooth cluth engagement into 2nd gear. 9000K rpm in 1st is about (plus or minus 300) 5500 in 2nd but if he releases the clutch quickly the motor is well above 5500 RPM's causing the car to jerk or surge forward.

A slipping clutch would actualy make the whole process much smoother. That is why I am suggesting he feather the clutch engagement.

 

make sure the clutch is not slipping.

 

Footman is very specific with his concern and it appears in his first post; the engine RPMs do not drop quick enough to accomodate the quickness with which he wishes to shift his transmission. A lightweight flywheel will provide the results he is seeking.

Also, I do not think the gear spread between 1-2 is as extreme as you think, Highway. I seem to recall it being 9K-6.3K, or so.

 

I read it as his rpm is hanging up high and not dropping fast enough during his shift.

Could be technique but could also be a slipping clutch. Never hurts to have him check.

 

Oh I know his complaint and a lightweight flywheel would help, but technique is part of the problem. I run your lightweight flywheel and I can still shift fast enough between 1st-2nd and 2nd-3rd to have the RPM's hanging above the new engine RPM once the shift is complete. The fact is, if you dump the clutch the shift wont be smooth. 2nd to 3rd is hardly noticable but 1st to 2nd you need a little feathering of the clutch. A smooth shift makes for a faster launch.

According to this thread 1st to 2nd is 5670 and 2nd to 3rd is 6525. I haven't done the math to verify but it sounds right to me.

 

Hanging up high yes, but its before releasing the clutch not afterwards. He wants the shift and clutch enguagement to be smooth. A slipping clutch woud make for a very smooth shift.

 

I have no clutch slip.

Technique-wise, if I let out the clutch slower (feathering), then yes it will be smooth, but would that not mean I am slower? I am after a faster shifting time while maintaining smoothness.

Charles R. Hill understood my concern by the way.

So looks like I need a lighter flywheel to achieve what I want. Can I use the stock clutch with an aftermarket flywheel (RB or Mazdaspeed for example)? I like to maintain the feel of the stock clutch as its comfortable to drive with on street.

 

It wont take much feathering to keep it smooth and that wont slow you down.

I understood your concern, I just dont think a flywheel alone is going to resolve your complaint. Honestly the condition you have described is present on vertualy every car. The 1st to 2nd shift always has this so called problem.

Yes you can run the stock clutch or I would recommend the exedy mazdapseed heavy duty clutch. Part # 10803AHD It has a very stock feel but with an increase clamping force.