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I belive its ~10 kg for the 1.6...

why do you ask?

wun911 wrote:I belive its ~10 kg for the 1.6...

why do you ask?

the lighter the better?

I think the 1.8 is 15 mm wider and its about ~2-3k heavier. Larger heavier rotating mass holds more inertia, blah blah blah.
Interchangable between NA and NB they both take the same clutch alignment tool etc.

I'm pretty sure I read on a jap site the NB8B flywheel weighs 11kg minus the ring gear, im in the process (STILL) of getting a lightweight flywheel, 4kg including ring gear, and a exedy Button Clutch installed, just trying to get some cash together. Lol

wun911 wrote:Interchangable between NA and NB they both take the same clutch alignment tool etc.

yep, but you need to change the clutch as well as the flywheel. some people run 1.6 clutch and fly on the 1.8 as it revs easier. and some turbo 1.6 guys run the 1.8 clutch and fly coz it's beefier and less prone to slip.

Speaking of flywheels, is a lightened flywheel on a Turbo 1.8 much of an advantage?

2 schools of thought on that one. you might get on boost earlier with a lightened flywheel, but revs will drop quickly on gearshifts meaning you'll need to build boost again. whereas with a normal / heavy flywheel , the revs will stay higher during gearshift (more momentum) so you'll still be on boost when you select the next gear.

OK got it; Keep the same flywheel, just give it more boost.

I have heard LFW has very little influence on when boost comes one... correct me if im worng thogh.

1.8 Flywheel being slighly larger can hold more clamping force for less pedal effort, makes life easy.

Just because two flywheels are almost the same weight give take 1-2kg does not mean they both hold the same amout of inertia, it is more important to remove weight where it counts.

Wun, surprised you haven't gotten one of emilio's 7.25" flywheels yet...
http://forum.miata.net/vb/showthread.php?t=303542

My turbo racer has an ACT Pro Race flywheel and it does nothing but help. Less rotating mass is always the goal for performance engines - turbo or na.

yes , thats why i stuck with the 1.6 flywheel when i turbo'd my car, rather than go the heavier but stronger 1.8.

i was just offering the 2 schools of thought that had been put to me when i was making enquiries about which path to follow.

I've just replaced my flywheel on my NA6, and it weight 7.9Kg (with ring gear) on my bathroom scales, and the one I replaced it with is 4.1Kg. My clutch works well on the street, still very easy to drive, but it is noisier, especially when off the throttle at high revs. Not sure why, but I have heard that it is a common occurance with really light flywheels. If anyone can explain why, I'd like to know why they are noisy.

At that weight its probably aluminum, aluminum flywheels are usually more noizy than stock (shaved down) or chromomoly.

I have an NA8 flywheel sitting out in the shed. If I remember when I get home I'll pop it on the scales