need help with flywheel

[Pastor_Protege]

I am getting a clutch master stage 2 clutch for my 94 LX. While I have things apart I want to do something with my flywheel. I want to know if I should go with a new aluminum flywheel or machine the factory one for weight reduction. I want to hear from people who have done both as to performance benefits and drivability. Thanks for any help you can give me and Happy Easter to all!

[matt_fulghum]

never mill down a factory flywheel.... don't be a cheapass. Buy a real lightweight flywheel.

[ROB-80E]

I took 2Kg off of a 1.6L carby flywheel to put on my BPT engine (i was running 1.6L transmission), but after 12months went back to a full weight flywheel for the torque and also control factor.

In racing, it was either a bog down start or too much wheel spin. I could never get the take off's right with the lightened flywheel.

After the 12 months with a high performance clutch, there was no signs of adverse effect to the flywheel.

[matt_fulghum]

well 2 kg isn't so bad... but generally when people talk about milling down their flywheels, they seem to mean milling off 5 or 6, and eventually it just starts to be a really bad idea... those damn flywheels are HEAVY

[Pastor_Protege]

I took 2Kg off of a 1.6L carby flywheel to put on my BPT engine (i was running 1.6L transmission), but after 12months went back to a full weight flywheel for the torque and also control factor.

Thanks for your responses. I thought that a lighter flywheel would give you more low end torque. Also wouldn't a new aluminum flywheel make launching even harder than taking a couple pounds off the factory one?

[Pastor_Protege]

Please impart more wisdoms to me. To aluminum flywheel or not to aluminum flywheel. That is the question.

[D323]

I have a 9lb aluminum flywheel, but I havent installed it yet.

Please explain how lessening the weight that the engine has to spin reduces the amount of low end torque? If anything a heavier flywheel will need more torque to rotate, increasing drivertrain losses, and reducing the amount of torque at the wheels.

Oh and excessive wheel spin would suggest more low end torque, making for more difficult launches. But then again I always welcome more torque when building a motor for a car.

[Pastor_Protege]

I have a 9lb aluminum flywheel, but I havent installed it yet.

Please explain how lessening the weight that the engine has to spin reduces the amount of low end torque? If anything a heavier flywheel will need more torque to rotate, increasing drivertrain losses, and reducing the amount of torque at the wheels.

Oh and excessive wheel spin would suggest more low end torque, making for more difficult launches. But then again I always welcome more torque when building a motor for a car.

That's what I thought too. Let me know how you like it when you get it installed as far as drivability goes. I know that you have to launch harder with a lighter flywheel just to engage the clutch. My friend tells me that an aluminum flywheel on a daily driver would be a real pain in the a$$. He says you would have to almost squeal the tires every time you wanted to go forward. Another guy I talked to who has an aluminum flywheel on his mx3 says it's not that bad.

[D323]

That's what I thought too. Let me know how you like it when you get it installed as far as drivability goes. I know that you have to launch harder with a lighter flywheel just to engage the clutch. My friend tells me that an aluminum flywheel on a daily driver would be a real pain in the a$$. He says you would have to almost squeal the tires every time you wanted to go forward. Another guy I talked to who has an aluminum flywheel on his mx3 says it's not that bad.

Tire squeal? What tires was he using? What suspension work did he have done, if any?
I know my friends civic with a gsr in it would squeal the tires.... but that was b/c my friend had cheap ass stock tires that came with the car.... They were bald anyways and replaced shortly.

Right now there are some crappy ass general tires on the MX, and I cant bear to ditch them, I mean they still have the stubble things on them. I am probably gonna burn those off and then get a good set of 7in wide rims with some fat tires on it.

[Pastor_Protege]

I don't think he was speaking from expirience. He just meant that you might have to launch hard all the time with a real light flywheel. I am not sure if he's right or not.

[Vash00es]

If your speaking in racing terms, a heavier flywheel will have more momentum then a lightened version, and will therefor give you better launches when you drop the clutch.. and in another retrospect, a lightened version is better at the rest of the job, so you decide

[D323]

If your speaking in racing terms, a heavier flywheel will have more momentum then a lightened version, and will therefor give you better launches when you drop the clutch.. and in another retrospect, a lightened version is better at the rest of the job, so you decide

define better launches?
If your getting ready to launch then your already on the gas holding the motor at a specific rpm... really momentum has nothing to do with the flywheel at that point. Momentum is the urge of the wheel to keep spinning on its own. Hence why heavier flywheels are used in daily driven cars - not thought of as a quick shifter in a daily driver and the momentum is need when coasting on the highway or when going from gear to gear.

After dropping the clutch a lighter wheel gives you the edge. Less mass to rotate = quicker acceleration. Momentum may be there to keep the flywheel rotating while the clutch is gripping against it, but it also depends on the clutch.

I dunno its hard to say. There's probably a good bit of momentum that is lost when the clutch first bites into the flywheel... where a heavier flywheel might tend to hold its speed better when being gripped by the clutch. But then again the motor is still rotating the flywheel and since it is being powered, I dont know how much momentum comes into play here if any at all.

IMO you make up for the loss in momentum with the quicker acceleration. Yeah momentum is nice at higher speeds when you want to retain motions, but these are FWD I4 motors... not really built for top end.

[bandman659]

With a lightweight flywheel, the engine will rev more freely. There is less to stop the rotation of the engine and less to stop it's rotation. The lightweight flywheel will make it much easier to bog to engine at starts because of how easily it loses revs.

[FE3-323]

any experience i've had so far with anything above a stock clutch has chewed the **** out of the stock flywheel.... why i don't know. this leads me to beleive i won't have an alternative option other than a lightweight which i don't want.

[neuspeedescort]

i have run both a lightened and stock wheel on my gtx.

granted i had a bad clutch from ACT when i used the lightened wheel i still hated the ligher one. the clutch was bad do to not fully gripping 100% of the time. it was a bad run on a part number from ACT. it helped me get home that was the only reason i used it. getting home was a 3 hour drive and then to work a bit for the next couple weeks til the correct clutch was shipped to me. the lightened ones rev up and down faster. it makes it more fluttery. when my clutch was holding i would get up and move but the R's would drop faster between shifts. making it not as smooth of a shift if i was daily driving and needing to leave my foot in it a bit more when on it.

when i put the stock one in i can get third gear churp on my 18's if im shifting good. the torque is noticeable higher. i also ran this with the same ACT clutch as with the lighter flywheel. its not like your making that much more its putting you in your seat harder. its just that you have smoother shifts and more sustained rev levels. its hard to explain unless you run both.


NEUMAN