7mech

I'm more than likely going to need a knew clutch setup in my car so I thought I would get a clutch and flywheel combo. Which one of these combos would bebest for drag racing and some spirited street driving?

The SR Motorsports 9.5 lb alluminium flywheel with counterwieght, hardware, bearing kit, and ACT street/strip clutch for$799.

OR

The Racing Beat 12 lb alluminium flywheel with counterwieght, hardware, and ACT street/strip clutch (from RX7trix) for $741.

I know that a lightened flywheel will help me, but I was wondering if the 9.5 lb flywheel was to light for daily driving and drag racing? Also if there is a representative from SR Motorsports on here could you maybe give me the 11 lb flywheel instead of the 9.5 lb one for the same price? Just asking. Anyways, any advice is really appreciated. Thanks.

Jerk_Racer

I have the 9.5# unit and it is great for spirited drivng. Daily driving is not an issue either. It won't affect your idle or stall out on you like some might say. But it is not good for drag racing. The 12# unit might be more for your taste. It's a compromise anyway you cut it. The stock unit would be best for drag racing, as it's the heaviest. The 9.5# lets the revs climb and fall a helluva lot faster than the stock unit. It's your call in the end .

pengaru

lighter flywheels store less energy so it can be annoying for drag racing, but it really is not that bad, it will hurt you right off the line but after that it improves acceleration significantly... so it would be beneficial either way... and I was able to shift more quickly with the aluminum flywheel since the R's would drop quicker.



But the difference between the 9.5# and 11# and 12# is probably very minimal, it really depends on where the weight is in the different flywheels... They should say the flywheels moment of inertia, not just the weight, since that's what really matters.

annoying.

7mech

Well I just talked to a good friend of mine, who I thought had the 9.5 lb flywheel. Turns out he has a 17 lb steel flywheel. He said the alluminium ones are not meant for drag racing because they warp too easily. Have any of you had this problem? Does anybody know where I can get the 17 lb steel flywheel at as combo with a clutch? Thanks.

Jerk_Racer

Aluminum warps too easily? That's a new one on me.

I just guess it depends on how much you are into drag racing. Sounds like you want a well balanced all around car. I'll tell you what, once I had that 9.5# badboy in there it was happiness after that. pengaru is correct. It does accelerate quicker. You car will feel a couple of hundred pounds at some points. The engine will feel like a what a sports car engine should feel like. Try it, you'll like it. You car should still be deep in the 13's (I guessing by your mods)



BTW 7mech, do you get boost creep?

7mech

Yes I get boost creep. Sometimes I hit about 12psi on cold nights. Most of the time it doesn't go above 11psi. I also fall back down to about 7psi at about 6k rpm. How is the 9.5 lb flywheel for everyday driving. Is it a pain in the *** or is it only a little bit of a change? What I meant was they tend to warp do to the excessive heat that standing lauches create. Is there any truth to that?

Jerk_Racer

Whoa, you get less creep than I do. Duh-oh!



There might be some truth to that, with the warpage from the abuse like that. But you'll also kill clutches as well when you do that. (So I went to a doctor and told him it hurts when I do this: So he told me not to do it.) You could look at it this way: there's probably less heat made from the clutch trying to slow down the flywheel. Less weight to stop in an instant. I've had mine for over a year (about 8k miles however - I live a mile from work) and it's still as stong as day one. I abuse it on an almost daily basis plus tons of autoX'es thrown in for good measure. It's still good with 265rwhp (I still need to scan that dyno sheet ) day in, day out.



The flywheel from SR Motorsports isn't all aluminum. It has a steel ring gear and steel friction plate. Both parts can be replaced if for some reason they fail/get worn out.



Daily driving is OK. It took me a few miles to get used to it. It suits me fine and I'll never go back to a heavy one. Starting from a dead stop after sitting at a red light on a steep incline isn't too dramatic. Just feed it a few more revs. It'll become instinctive to you.

7mech

Yeah I called around to a few shops today and got the skinny about them. All the guys I talked to said not to get one for drag racing. They said that because they are so light they don't help youwith your launch and aren't worth it. They all recomended that I stay with my stock flywheel. I think I'm going to save my money and stay with the stock flywheel. Thanks for all the info though.



BTW what year and model car do you have? I think you get more creep and drop off of boost with the more HP(with stock turbo).

Jerk_Racer

It's an '89 T2. Blitz SUS intake, no TID yet, and a full 3" exhaust. Even with the Profec B set low (9# on low setting), it goes up to 15#. With the bolt-in silencer tip plugging the exhaust I can control it.

7mech

Try adjusting the sharp and mild **** on the controller. That on cotrols how quick your wastegate opens. I think mine is set on full sharp(not sure because my car is at the shop and I can't look at it). I just looked at the Profec B instruction manual and by doing that I culd tell mine is set at full sharp. Also check to make sure that you have the selector setting(numbers with pins on back of controller) set at 4 down, 3 up, 2 up, 1 down (actuator type when overboost occurs). This should solve the problem or atleast get it close to where you only overboost 1 to 2 psi depending on air temp. Do you get alot of overboost in 4th and 5th gears?