Where do you get this information from? Have you driven a Miata with a lightweight flywheel?

My flywheel is around 8lbs and is totally streetable. I've never stalled the car or had any issue. I wouldn't do it again since I don't think the performance gain is justified considering the cost. In fact I think paying anything for a lightened flywheel (stock or otherwise) is a waste of $$$ on a FI'd miata.

When you had the flywheel balanced did you get the PP and Disc done as well?

 

sorry, didn't mean it to come off like gospel or anything

looking around at aftermarket lightweight flywheels, the "race" designated wheels are around 8-10 lbs and the ones designated "street" are around 12-13 lbs.

maybe there's not enough of a difference in rotational mass to matter and it's just marketing, but that's my observation

 

Honestly for me it was depressingly easy to get used to the flywheel. When I first got it if felt different, but after a couple of days it didn't seem different at all until I drove someone else's with OE flywheel.

 

I heard everyone saying that too, so when I bought my 8lb flywheel and ACT Extreme clutch, I was worried it would kill the driveability. Even the first day debunked everyones comments about not being able to street it.. I now realize that I heard it mostly from miata.net, which explains alot. After two weeks I got so used to it, that it was actually harder to drive my friends car with a stock clutch.

 

I drive in stop and go traffic with it and it's fine. But there are aspects about it that don't outweight the good IMHO. that's why I'm going back to OEM.

 

nahhhhhhhhh. my whole rotating assembly is like 15 lbs including flywheel, clutch, and floaters. plus it's smaller diameter. it's only a bitch because of the mazdaspeed shifter and different type of engagement feel than stock.

but it's not hard to drive. just notchy. OH that reminds me... gotta find some good gear lube. brb.

 

The only thing I don't like about my lightened OEM flywheel is that it increased the gear noise my tranny makes :(

 

lightweight flywheels and the increased ease of heel-toe driving = well worth it in my book.

If you don't heel-toe rev match... don't bother with the flywheel.

 

Is it really that bad? I know alot of people complain of the same noise. I think mine may have made it alittle bit louder but I really didn't notice much. My flywheel is aftermarket tho, maby thats why, idk.

 

Well, my tranny was pretty bad with the stock 1.6L wheel...it definitely got worse with the lightened 1.8L fly, but maybe only a handful of decibels.

 

I've been wondering about this.

I'm going to be doing the clutch eventually, and I almost always to a lightweight flywheel when I'm putting in a new clutch. I heel toe subconciously now, so any weight lost seems worth it to me.

I'm thinking that I'll just machine some off the oem. Does anyone know why it creates the excessive noise?

 

that's a good question, I would assume it has something to do with sympathetic frequencies creating a resonance.

 

I was gonna guess that there is just less mass to absorb vibrations, thus chattering. I got a c+ in both semesters of physics though :(

 

i had no idea they got louder after that? what gets louder exactly? does it get unbalanced when you do that? do people not balance it afterwards?

 

it just does it apparently, people do balance it and it still does it.

 

Typically people describe the increased noise as heat sheild rattle on deceleration. I got that after going to the aluminium flywheel. Before the flywheel I had a slight rattle when idling, people have called this gear lash. After it is much more amplified.

 

"An aluminum pan rattling ontop of your tranny" is what most have described it as.

 

I have never known a lightened unit to increase noise, stock or aftermarket. Guess I will soon find out when one of my spare 1.8L flywheels is machined down a few pounds.
Oh joy... I get to install a clutch... when I find the time.

Jason

 

Jason, if you had no rattling in your tranny to begin with, you may not notice any increase in noise because there isn't enough to get amplified.

If your tranny's old, tired and beat-up and made noise with a stock flywheel, as mine did, it'll almost surely get worse with a lightened flywheel...as mine did.