To Go Lightweight Flywheel or No?
 

Planning a turbo build for fun on the street, and was curious if people prefer a lightweight flywheel, stock or 'lightened' stock....with a Stage 2 clutch. May have a few track days or autocross events, but 90% on road.

Opinions? Yay or Nay for a lightweight flywheel?

Personally I love a light flywheel, but you will get some mixed opinions. I initially moved from a stock 1.8, to a 13# ACT streetlite, then to a 9# Fidanza. People talking about drivability concerns pushed me toward the 13# flywheel initially, but I didn't have any issues and I was much happier with the 9# flywheel.

One thing is for sure through, if price is a concern, just skip the flywheel and spend your money on a decent disc + pp (FM/ACT are popular). This site is full of terrible experiences with "Stage 2 ebay clutch and lightweight flywheel"; there's no need to go that route, it's been done, unsuccessfully, many times. You should really consider getting a decent clutch so you're not pulling the trans to replace it again in a week.

Great to know, thanks. With the turbo setup I'm staying stock internals on a low mileage 1.8 and keeping 5 speed. So not excessive power, but would like to hit decent numbers with a GT2560R. Definitely going to get a brand name Stage 2 clutch, I've seen the FX stuff online but just don't want to risk any issues. Since price is always a factor I'll probably go with a used flywheel, if I can find one. New for the clutch, unless someone has a low mile set....in obvious good shape.

Exedy, Clutch Masters, South Bend, ACT and SPEC are the ones I'll probably choose from. Full face as its 95% a road car. Any thoughts on these companies?

Consider this setup as well.

SuperMiata Sport Clutch Kit Miata BP

I've been driving several Miatas including NA and NBs with stock flywheel. Jumped onto an NA with the SuperMiata clutch and flywheel kit the other day, and it was actually fairly easy to drive. Personal opinion, tho.

I'm on a FM stage 2 and 13# flywheel - I had them balanced together - not real driving issues.

Great to know all of the above, thanks for adding the insight. I just picked up a Flyin Miata flywheel and will be deciding on a clutch next.

The Supermiata that was listed meets expected power and is pretty reasonable on price. But, I noticed that the clutch plate has the same design/spring configuration as the M-Pact that is sold on Rock Auto. https://www.rockauto.com/en/moreinfo...pt=1993&jsn=18

Anyone know anything about M-Pact clutches? It also seems to be similar to the PPC/XTR stuff on eBay. Not trying to cause a sh*t-storm here as pad materials make a difference, but wondering...thoughts?

Thanks again.

I had the ACT XTSS prior to upgrading to the BMW transmission and it held 300+ hp. It used a strong pressure plate and a street compound disc with a smooth engagement. Pedal pressure was a little higher than stock but not bad. I didn't enjoy stop and go rush hour gridlock but who does? The HDSS is the same disc with a lighter sprung PP, if you aren't planning on huge power.

When you think about it the stock flywheel was designed by Mazda to allow you to pull away smoothly in a two up fully loaded with luggage car. If you mostly drive alone and have lost some weight from the car a lightened flywheel makes great sense. It's free acceleration.

It's also the main damping of fluctuations in crankshaft rotation speed from cylinders firing, compressing, etc.

FM1 with 13lb flywheel here. My friend has an FM1 with the 10lb. Both are easy enough to drive. The 10lb is noticibly easier to stall but does rev a bit snappier. That said, for a street car, I much prefer the 13lb one in mine and would go with it again.

You can't tell the design of the clutch from looking at a picture on a website. Our clutch is made to our specs in the USA by Centerforce, a well-respected clutch brand. They are not even the same as a standard centerforce clutch you can buy elsewhere, let alone being the same as Rockauto/eBay.

If you haven't yet, read the description on our site explaining the differences between our clutch and others.

Our Sport clutch (organic) mated to the flywheel you already got would be *sweet* for your build. Excellent modulation, light pedal feel, plenty of power holding capacity.

https://supermiata.com/SuperMiata-Sp...-Miata-BP.aspx

M-Pact = Competition Clutch private label. No connection to us. More in common with a certain private label clutch from another vendor..
Competition Clutch, "CCI" HQ is about 40 minutes from the LLC that makes XTR clutches in GA