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Lightened Flywheels, worth it?  

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In brief, either my spigot bush or thrust bearing is dying (horrible noises when the clutch is disengaged), so i'm changing my clutch. Already have an Exedy heavy duty clutch kit with new thrust bearing, and got a new rear main, spigot bush and input shaft seal to put in while the gearbox is out.

I've been doing alot of reading:

http://www.skylinesa...is-it-worth-it/

http://www.skylinesa...tened-flywheel/

http://www.skylinesa...ened-flywheels/

(to name a few)

And there are alot of mixed opinions about whether or not a lightened flywheel is worth it. So put together this poll in simple yes/no/unsure style. I can easily get the standard flywheel machined, but I can also get a Nismo Chromoly lightened one at a very good price, and brand new.

My car is %100 daily driver at the moment, but once it's up to a "reliable" spec, and the budget allows, I intend to have a go at drag racing, and eventually (long term) some track work.

Keeping in mind it's DE+T, so the low end response is already pretty good already, but still looking to improve.

All opinions appreciated, and hopefully anyone looking at this in the future can benefit from it. thumbsup.gif

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Yes it is worth it. A CroMo one will be about 1kg lighter and will fell like it gives 200-300rpm earlier boost threshold. That's pretty good, for the cost.

Lightened flyweheels, as in flywheels that have been machined down to remove weight, should be avoided whenever there is an option to buy a brand new lightweight flywheel. Alloy flywheels seem to offer a mixture of real lightness and shocking chance of crapping out. Especially that useless brand that starts with an F.

Also depends on clutch. If you get a twin plate, don't get a lightened flywheel for a daily driver.

It'll make it nicer to actually use.

Didn't get a twin-plate for that reason, just a slightly better Exedy item over the factory one.

I read that due to the low compression DET engine, take-off and low speed driving can be a p.i.t.a. But figured for a N/A it should be manageable with a reasonable clutch. Drove a GTR with a twin-plate clutch and was not a fan, not for a daily any way.

Didn't get a twin-plate for that reason, just a slightly better Exedy item over the factory one.

I read that due to the low compression DET engine, take-off and low speed driving can be a p.i.t.a. But figured for a N/A it should be manageable with a reasonable clutch. Drove a GTR with a twin-plate clutch and was not a fan, not for a daily any way.

I have a 4 or 4.5 kg flywheel in my nearly standard GTS-t. Didn't really notice any difference on hills, low speed driving or take-off. If anything it decreased NVH when bogging down the engine.

Engine does seem a lot more responsive when rev matching though :)

I'm happy enough With my NPC Flywheel

Billet with cooling vents in the centre for my NPC single plate button. It was more a piece of mind thing for me over anything else. Im not really chucking out the power to be throwing flywheels around but nice to have a new one, and know that at least im getting some cool air to the centre of the clutch.

Rev wise, its a bit more responsive but not a great deal that I can tell..... Mine weighs 6.6kg, been meaning to weigh the stock flywheel, has anyone got a weight for it? Dont think its much heavier but

I'm happy enough With my NPC Flywheel

Billet with cooling vents in the centre for my NPC single plate button. It was more a piece of mind thing for me over anything else. Im not really chucking out the power to be throwing flywheels around but nice to have a new one, and know that at least im getting some cool air to the centre of the clutch.

Rev wise, its a bit more responsive but not a great deal that I can tell..... Mine weighs 6.6kg, been meaning to weigh the stock flywheel, has anyone got a weight for it? Dont think its much heavier but

If you don't mind me asking, what did you pay for it? Or was it part of a kit?

Do you believe it was good value for money in terms of response/feel etc, or would you "not do it again" sort of thing?

  • 3 months later...

Also depends on clutch. If you get a twin plate, don't get a lightened flywheel for a daily driver.

It'll make it nicer to actually use.

Shaft me sideways! If you want easy driving get a Auto FFS! :laugh:

I've got an Exedy twin plate with the lighter flywheel that came with it, it takes some skill to drive but it just revs so much more responsively with the lighter mass. The heavy fly wheels make cars feel like slugs in comparison.

+1 for the NPC steel billet lightened flywheel (6.8kg)

I reckon it is magic! The engine is much more responsive; quicker to rev, easier to rev match on down shift and better to drive all around!

TBH I haven't noticed any down side to it at all; motorway, carpark, around town and through the hills it is all good.

If you have to replace the clutch anyway it is an option that is well worth considering...

For less than the price of a Jim Berry full monty I got a clutch (10" HD Organic; good for 300+rwkw) and flywheel from NPC!

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