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lightened flywheel Q's...

4583 Views 6 Replies 7 Participants Last post by  EchoWrx
i have a feeling it's going to be time for a clutch soon, so might as well stick a lighter flywheel in there, right? :D what's the lightest weight i can get away on a 1.8L with without making the car undriveable in traffic? i know running lightened pulleys on the engine rules out something like a fidanza on a 2.5L, but with a smaller engine...? i'm not sure what the rule would be. that's why i'm asking. :lol:
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The Fidanza is nice, because it's LIGHT :) You are right if you use light weight pulley then a light weight flywheel may not be a good idea, because the engine will definitely have a hard time idling, resulting in rough idle...also, in some cases stalling problem may occur when clutch in fast during higher RPM, although that doesn't happen to ALL. What I understand is that unlike US cars, we don't have an actual harmonizer, so the pulley and flywheels are serving as that purpose...therefore, changing both to light weight will have a high chance of defeating this purpose. I don't think a 1.8L is any different b/c the design behind is the same...I hope you can understand my poor English and Good luck to you :)

I'm interested in understanding the "rules" on using lightened pulleys in conjunction with lightened flywheels. I just installed the N1 3 pulley set (not underdriven) and was seriously considering installing a 14lb flywheel as well. Would this be bad?? What combinations, if any, are recommended. I chose the 14 lb due to the fact that it isn't super light, but what is the point of diminishing returns? Any possibility of engine damage with this combo?


- Tokay


Racecar- Sorry for hijacking your post, but I thought it might also relate to your question...
If you want a lightened flywheel, sell the N1's and buy a Fidanza. Its alot more cost effective than a more expensive FW and the N1's. THe stock crank pulley has rubber in it, so it absorbs vibration. The stock Flywheel has no apparent additives for vibration absorption, so I would lean towards the flywheel does nothing for vibration. With the N1's and a 14 pound flywheel, you are basically at Fidanza levels of crank lightening anyway, but for easily twice as much money, with out the stock crank pulley on the engine with its peculiear rubber ring. I prefer to leave the stock crank pulley on, but the weight of the system would be fine with a 14 pounder, the other things are up to you thogh.

THe 1.8 liter should be able to run a Fidanza. You should just call them and talk to one of their people to see what they say about it.


if you do decide to go with the lightweight flywheel and do sell the pullies i would be really interested in them so let me know whats up.
Experince with opinion

Mine and my buds experince so far:

Bud1- has a stock 1999 dohc RS (mainly stock) he shatered his stock pully to bits, Now scared to use anything lightened.

Bud2- Has a 1999RS-Turboed well modified. Has uprated Clutch but he wont use lightened pully or flywheel. Reason being that he produces too much torque and is slowly bending the teeth in his stock transmission. When he races he doesn't drop the clutch because his tranny wont take the torque. He is looking into rebuilding his trany with stronger parts. The heavier flywheel helps soften the blows the stronger engine is belting out.

My car(y2kRS) has an Unorthodox racing UD pully everything else is stock. So far it works well and now better that I have put a better muffler and intake on. They helped smooth the engine out the pully didn't like my stock muffler (too jerky) before.

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