I just read that the MS3 and MS6 now have a lightened dual mass flywheel option. Outstanding work and a big thanks to SSInstaller.
Since a group buy is already in the works I thought it would be important to share some knowlege I have on them.

1. With out a doubt; there is nothing better to make an engine rev quickly than adding a lightened flywheel. (ok arguably Titanium or Aluminum connecting rods); but hands down LF's are one of the single most important mods for reducing rototational mass on the crank assembly. Freeing this load on the engine will increase power output for sure on even a stock MZR engine.

2. All things have a cost however. Lightened flywheels, while they allow a engine to rev really fast, they also allow the engine to drop revs really fast. Example: when you get out of the throttle quickly. IE, you push the clutch (for long enough time to return to idle) from a high RPM you might find yourself restarting your car. This is because the engine revs will drop so fast the ECU might not be quick enough to recover the environment change. (this has yet to be proven on the MS platforms, but this has been my experience with other applications). Quick or normal shifts betwen gears will not be a problem. see # 4.

3. Lightened Aluminum flywheels typically transmit noise. IE throwout bearing noise. It's sounds like a rattle but only at idle. (Again this has yet to be proven on the MS platforms, but this has been my experience with other applications). However, loud/open exhaust or slightly increasing radio noise can typically muffle the noise.

4. Loss of torque for clutch engagement. Less rotating mass means clutch engagement will probably need to be made at slightly high revs to get the car rolling. It will certainly take a little getting use to, but basically it only means relearning the sweet spot(s).

I hope this helps in your decision. Look out EVO's and STI's the Mazda game is getting pretty serious.

thanks alot scott!!!

Good read =)

Makes me want mine more!

But it will wait until december!

Just one thing, You're really losing inertia not torque. Other than that, I have the Fidanza for the v6 and it kicks ass! I'm sure this will too.

Outstanding post! Thank you! I am interested in a light-weight flywheel but I didn't know about some of these ramifications.

Wow great post

and thank you!

+1 this would solve my issue of revs not droping fast enough for quick gear changes!

Y

does anyone know what the stock flywheel weights? I belive that the AM one is 9lbs... Then you can really determine how big of a change it will be with revs and what not

Great write up. I had a lightened fw on my SVT contour and I loved it. Def took more revs for engagement but I got used to it.

The package with my OEM flywheel weighed 39# at UPS, so without the packaging it's about 37~38#..

Thats pretty heavy...

I HONESTLY believe that 9lbs is just too light for this car given the AWD, weight of the car, power band, and clutch engagement... Daily driving is going to be a chore and get used to alot of stalling intially, especially on hills.

15lb would be a MUCH better choice IMO....

That 39 lbs is what makes getting a 3600 lb car with no lowend TQ (assuming your out of boost and below 2K rpms) moving so easy!

I think the reason the light weight flywheel ended up at 9 pounds has more to do with the size of the OEM part than anything else. They can only use so much aluminum and keep the stock dimensions, and if they made it out of steel it wouldn't be much lighter if any...


We'll just have to wait and see how it performs.

BTW, who would be interested in a aluminum driveshaft??

how about a carbon drive shaft

CF is lighter, but you would be looking at about twice the cost...and the only custom driveshaft shop near me uses aluminum and steel only.. But if anyone in Florida wants to take as trip to PST to get measured we might be a ble to get a Cf shaft made, but expect it to cost $1300~1400 vs. $700~800 for aluminum.

I'm sure someone down here wouldnt mind. There are members all over Fl. I would never get one, but I wouldnt mind taking going there for a day to get measured for those interested, if it were close. Where's PST located? I think I remember someone a whlie back looking into getting one down here, maybe south or east fl that could get one here for 1200.

Based on what y2kcowboy has listed regarding a lightweight flywheel it seems the cons out way the pros. For those such as whoosh and SSinstaller what are your reasons for going this route? This mod seems like it would make since for a track car but not so much for a daily driver. I'll be interested to see what people say once this is available and installed on their cars.

I had a fidanza flywheel on my prelude and loved the way it improved throttle response. It was also very light IIRC.

I don't think that this is going to pose as big a problem with drive ability as most are assuming. You might have problems with unsprung clutches, but for a sprung hub clutch you'll probably just need to slip the clutch out at a slightly higher rpm.

The pros will far outweigh the "cons" after you drive the car and adjust to the way it responds, unless the cost is just out of reach. It wouldn't be a mod for everyone though, unless you're after all the bolt-on power you can get. Been running light flywheels for(ever) on the street (& track) and have no problems.

This makes since and doesn't seem all that bad. I guess the down side would be a slightly shortened life span of the clutch over the use of the stock fly wheel. In exchange for faster revs and better WOT shifts. Just like any mod there are pros and cons just a matter of whether or not you can live with the cons.

I have to completely agree!! 9 is just too light for a "6"

I had a light flywheel on my scooby, it was a love / hate relationship.

Loved how it would rev up, felt like I added big hp! Never died when pushing in the clutch at higher revs as mentioned earlyier.

Hated city driving and starting off!!! It took a looonnng time to get used to starting off from a stop, killed it many times. Lots of clutch slipping to start out. (note to guys planning on getting race clutches!)

My opinion is it would be great to get a dual mass flywheel at closer to half the weight of OE. Any less, on a Speed6, that is a daily driver, just ain't good!

This is nice because the one thing I really don't like about this car is how slow the revs fall. It takes forever and you have to wait for the revs to fall down when your rowing through the gears not at wot.
I figure this and the bs delete will help alot.

It is gonna help a TON dude it will rev like a motor bike, but I still feel, after having a 9Lb flywheel in my old car, this is gonna be too light for THIS application.... I almost guarantee 60 foot times drop compared to stock! (by drop i mean not as good, so i guess i should say 60 foot times will go up)

I had a Fidanza Flywheel (also 9 lb) on my mx6, for only about a week. It was grouped with a Clutchmasters Stage I clutch, and it rattled and chattered like crazy. (The clutch did, and I had it put back to stock.) It might have been an installation issue...

The flywheel weight itself was not of my liking for a daily driver, seemed like I couldn't start from a stop without revving the engine up and having a quick takeoff. As far as the revs dropping off too fast, I had to drive the car like a racecar to be able to shift without having to hit the throttle again.

All that being said, for you guys pushing big HP though I think this will be a great mod and I'll be following this thread outta curiosity.

I too had a Probe (same engine tranny suspension frame as the mx6) and that was dropping from a 23lb stocker to 9Lbs and THAT was a huge difference.... you guys realize your cutting down to like 25-30% of the stock weight, look up rotational inertia to fully understand WHY they put that huge FW in there to begin with then ask whether you REALLY want a 9lb FW.

The pressure plate also acts as a flywheel, and the BS, but 9lbs does seem a bit light for mixed use, esp with awd.

In my 7, I went for a 17 lb all steel, vs the super light aluminum mix. No regrets.

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Note light FW only delivers more torque to the wheels when engine revs rise quickly in lower gears. Other than rev matching, no power gain in upper gears.

+1

May see ~30hp in first, 20hp in second, and only about 3hp by 6th.

I have a 9# with a clutchmasters stage 3 in my 6s, NOT A MS6, but after having this in for a few months i would never want to go back to stock.
Once you get used to it, i think its easier to drive now.