Stalling - Lightweight flywheel problem?

[RX8SE3P]

I am bothered that my ZE MX3 seems to want to stall when you let the clutch out slowly, without giving it any throttle at all. I thought something might be wrong but I met up with a friend who has a Probe ZE and he has the same issue. He said it's because we're using the MX3 flywheel and it's too light. Maybe good for letting the engine rev faster but has less momentum since it's lighter. I guess it makes sense, why would mazda make a different flywheel for no apparent reason? Why not make them all the same and lightweight if it's such an advantage?

Anyone else experience this when using the MX3 flywheel or another lightweight flywheel on the ZE? My MX6 has a KLDE with a stock flywheel and that thing wants to drive itself off the line, it needs no throttle at all to get going, you just let out the clutch and it has no issues. Makes daily driving easy.

Opinions needed.

[fowljesse]

I think you're right. I've had this discussion with people excited about getting light flywheels, and UDPs.
If you had a 88HP RS with a 100lb flywheel, and serious traction, you'd kill a ZE in the ¼ mile. You get the flywheel going, and dump the clutch, and take off like a rocket. Remember those little cars that you'd push on the ground, and then let go, and they'd take off? The engine in it is just a "flywheel" and gears. You got the flywheel going by turing the wheels, and it's momentum in turn, kept the wheels going.
I don't like lightweight flywheels, for the reason you posted. Aslo, when shifting, you lose engine momentum.
The lightweight flywheel is good for when you don't expect good traction, because you can start at a lower rpm, and climp through the gears faster. So, you may get better drag times. Also, you may get better gas mileage, not to mention how impressive it sounds at stoplights, and parking lots.
My MX-3 can go through all the gears (on a smooth flat surface) at idle. It's built for lower end torque, and has the OEM flywheel.

[RX8SE3P]

Sorry jesse when you say you have the OEM, do you mean the KLZE/DE OEM or the MX3 OEM?

But yeah, I get serious vibration and stuttering when let go of the clutch slowly. I am almost regretting the use of my MX3 flywheel.

[onlytrueromeo]

The stuttering and vibration is prob from your clutch,not the flywheel...I have an mx3 flywheel on my ZE and get no such thing...do you have a pucked clutch? Jesse, having a 100lb flywheel probably wouldn't net you much in the 1/4 mile...yes if you COULD get traction you'd rocket off the line slightly better...but when have you heard of a ZE allowing a car to get good traction? Either way it would be more rotating mass, which is bad. You would lose less energy by losing "revs" but since when is that an issue when you are dragracing? You should be able to shift quick enough for revs not to drop by much at all.

[klmx08]

i wont think that would be your flywheel i have a clutchmasters flywheel which is even lighter than the stock mx3 one and i have never had that issue but sometimes when i push the clutch in going down hill my car will stall i have always wondered if that was my flywheel

[RX8SE3P]

Isn't it true though, that you lose some torque on small engines with a light flywheel? Our engines, even the mighty ZE cannot be considered big V6. Most V6s here in Australia are 3.5L or bigger.

I wouldn't mind hearing from someone who's had both flywheels in a ZE. I have a DE MX6 for comparison, which definitely feels smoother from almost 0rpms and no throttle.

[fowljesse]

I have the DE flywheel.

[klmx08]

im not sure about losing torque but i would take a couple pound loss to get the throttle response and increased acceleration my car feels alot quicker now.

[Nd4SpdSe]

I could see some problems if you had a 9lb flywheel, but with an Mx-3 flywheel, no way...it doesn't make sence for a more powerful motor to have problems with a flywheel that was stock on a lesser motor.

[marcdh]

I'm running 9lb fidanza - no regrets My car has never stalled due to my 9lb flywheel, unset TPS and idle valve yes. Lots of probe and mx-6 owners use mx-3 flys as a performance upgrade. I would suggest the lighter flywheels are a little harder to drive, and lose momentum faster creating a less smooth drive. Comfort and user friendlyness is often priority over performance in general consumer vehicles.

[Mr.mx-3]

Damn I bought a 9lb. fidanza fly/6 puck clutch kit didn't think it might do this. Haven't got anything in my car yet still waiting on Noyan USA to shipp my damn motor.

[Mooneggs]

hold on... this whole thread is speculation that a flywheel is causing your engine to stall? I'm sorry... but you are assuming alot. The first things you should be checking are TPS and IAC and probably even the VAF/MAF... if those aren't set right it's easy to think its something bigger

I know there has been some debate about the flywheels in the past (lighter vs heavier)... but let's not fuel that debate with assumptions and speculation (unless I missed some actual facts in someones response in this thread, then I apologize)

and once it gets a little warmer the NW mx-3 crew are going to be expermienting with each of our setups and maybe we can come back with some data for the whole mx-3 community (i.e. Mark vs. Jesse )

[RX8SE3P]

When I say stalling, I don't mean it's stalling it's a-- off. That's just stupid to think a flywheel would do that. I have tried setting the TPS many times. Also set idle to 650RPMS also tried a second TPS.

I'm gonna make it super duper CLEAR:

- When you let go of the clutch real slow and you feel it gripping - the car doesn't feel smooth, it feels a little shaky like a 4CLY in very low revs. Add a little gas, like 800RPMS total and it's fine. But my MX6, you let the clutch out nice and slow and it grips, it feels smooth, it doesn't give any hint of stuttering like it's about to stall and it can be at like 200rpms and never feel shaky or anything.

The only thing I can thing of is that my TB gasket needs replacing and also the intake pipe but there does not sound like any leaks.

I went for a ride in a friends Probe ZE, and it was also a little shaky when letting the clutch out. He said it was the MX3 flywheel and showed me by letting it out without giving any gas, it stalled. His car went hard once it was moving. That's why I am wondering.

Btw mooneggs, that sounds good, I would like to hear the results once you guys get together!

[onlytrueromeo]

Oh, well then, yes, thats completely normal...Dude really, how many cars can you drive w/o stepping on the gas when starting out? That seems silly! I always rev to about 800 anyway, maybe thats why I don't think theres a problem. The "stuttering" IS because of the lightweight flywheel...but is that really a big deal to you? When you learn to drive manual, didn't you learn to push the gas in while letting out on the clutch?

[Slammed6]

Sounds to me like you might be reffering to CLUTCH CHATTER! And why would you not press the gas to take off from a stop at idle????????
Also what RPM is your car sitting at idle?? You said bring the RPM up to 800 RPMs and its fine, I believe a stock KL should sit at about 750-800 RPM at idle from the factory.

I've had a ZE MX-3 with both MX-3 Flywheel and a Fidanza, and UDP, Clutch engagement was smooth with my Clutchmasters Stage 4 4-Puck.

I also had a DE MX-6 with stock flywheel, MX-3 flywheel, and fidanza flywheel. And almost every brand of clutch with those flywheels.