shifting faster...flywheel, short shift, technique, synchros

[czo79]

Hello all...
Interested in shifting faster. Finally got a short shifter, but I find that since I already had to wait for the synchros without it, I can shift the shifter faster, but I still have to wait for the synchros, so not really. I'm considering a lightweight flywheel...and wondering about its effects. Would this essentially make it so there is less work for the synchros to do? So one wouldn't have to wait for the synchros as long?
thanks....
Oh yeah...anyone have anything to say regarding lightweight flywheels used in conjunction with lightweight underdriven crank pulleys?
Micum

[Legacy777]

get new synchros

[vrg3]

With a lightened flywheel, it can be quicker to double-clutch than to wait for the synchros. But realize that unless you're double-clutching, a lightened flywheel won't help you shift any faster, since the synchros aren't trying to change flywheel speed; they're trying to change transmission layshaft speed.

There are transmission fluids that are supposedly designed to make synchros work better (which ought to make them work faster). Unfortunately many of them are GL4 and not GL5 like Subarus require. Many people have used GL4 oils and haven't noticed any ill effects, but I want my front differential to last until I don't need it anymore, so I'll stick to GL5 myself. Neo Synthetic RHD and Redline 75W90NS are both supposedly good GL5 oils for synchronizing.

Or you could invest in a nice dog box... :)

[czo79]

I've never driven a dog box...don't think I would want to learn how in my daily driver...
I wish that upgraded synchro gearsets weren't so damn much money...
I had a feeling that was going to be the answer to my flywheel question. Hmm...I wonder if I should still get one, just for the reduction in reciprocating mass, and so better acceleration.
Thanks
Micum

[vrg3]

I know Dave is very happy with his Exedy flywheel...

I'm sorry, I meant crashbox, not dogbox. Crashboxes are really tough and have wide engagement ranges for the dog teeth, so you can just slam them into gear. It's not quiet (hence the name) but it's very fast. You don't even have to use the clutch if you don't want to, but that subjects the engine to a lot of strain.

[czo79]

I was just reading something on NASIOC that a lot of people find that their 60' times go up after putting in a lightweight flywheel. Found that interesting. I guess I kinda figure that the lightweight flywheel must be kinda like a lightweight crank pulley times like 5 in how it affects the cars performance. I just wonder how much it affects the cars driveability on the street. If it doesn't help speed up my shifts...and only helps acceleration from reducing mass...and has negative effects on street driveability...I'm not sure I want it. Does anyone know what kind of interchangeablility there is with flywheels? Will the wrx ones work in a 97 GT? I assume 2.5rs ones would...are they all the same?
thanks
Micum

[entirelyturbo]

Yes it will affect street driveability for the simple concept of momentum: The lightened flywheel will speed up faster, but that also means it will slow down faster...

So let's say you're sitting still and go to engage the clutch at a rational 1000 rpm, like a normal street-driving situation. It is quite possible that you will stall immediately, because that momentum of the heavy, stock flywheel isn't there to help keep the engine spinning...

But I would love to have one just for its ease and quickness of rev-matching and double-clutching as vrg3 mentioned...

[Brat4by4]

Hold up, let the people WITH lightened flywheels speak here. It makes absolutely no difference in driveability. I cannot notice that it is some 6 lbs lighter or whatnot until I blip it for downshifts (then it makes all the diffence in the world). If you know how to drive a clutch then it is not a problem. The only times I stall ( ) are related to my clutch material which is Kevlar. It has different grip at different temperatures, so sometimes I let the clutch out for a smooth engagement when it is still very grabby, then blam... stall. I can count the number of times this has happened this year on one hand and have fingers left over, maybe just a thumb. Oh, and my quarter mile times are hovering right near 15.6 with just a flywheel, clutch, and engine/tranny mounts... which do you think is dropping almost 4 tenths off stock times? Besides my driving that is...

And the exedy is the only flywheel to get, by the way. It is the same one that STi uses on their OEM stuff. And STi doesn't do stuff on mass-produced cars that severely affect everyday driving. That's one of the reasons their stuff is so good...