2zr Monkey Wrench Racing Light Weight Flywheel Review

[tmontague]

I've had this on the car now for a week or so. I haven't done much spirited driving or highway driving due to having a week off of clinic and the ridiculous amount of non stop rain we've had here for the past 4 days. I've gotten enough experience with it to give a review of at least the city driving or traffic characteristics.

Although this is for a 2zr engine, this would be a very similar review for the 1nz engine if you install a light weight flywheel. The flywheels is 8.8lbs and it is CNC machine steel. I chose this over the 8lb Fidanza aluminum flywheel as it was $50 less and it is resurfaceable. I also trust steel more than an aluminum flywheel for a dd since it is sitting right in front of my crotch and if something goes, it goes bad. Just google broken flywheels and you'll find out what can happen.

IMO this is how this car should have come from the factory. All of the reports about having to give more rpm's to shift into first gear or being a pain in the ass in traffic seem blown way out of proportion. If anything the only real changes good or bad with the flywheel are that it makes the shifting much smoother all around. You no longer have to wait for the revs to drop between up shifts. You can now shift very quickly and no longer have to worry about the rough shifts or "bucking" that the car does.

The other big improvement is with heel toe shifting. I like to rev match down shifts and because the yaris drive by wire throttle is brutal and has a terrible response I often found myself not giving enough throttle when rev matching. This has a lot to do with there being too much slack in the throttle pedal, but also due to the stock flywheel taking a while to spin up.

With the MR flywheel the revs go up much quicker so a slight blip on the throttle makes rev matching much smoother and easier. I have found no difficulties with stalling due to low rpms when moving from a stop. This is also likely because of the crappy nature of the Yaris throttle which you already have to give a decent amount of rpms even with the stock flywheel.

The car seems to pull harder and faster to redline and is more noticeable in 1st and 2nd gears. At faster speeds the flywheel is not noticeable. After a week or so of driving on the new flywheel you become accustomed to it and the faster time to redline doesn't seem as noticeable. That said, the car is much more smoother now and IMO even better as a dd then it was before.

This is a modification that I would highly recommend doing, especially if you have the engine or trans out of the car for any other reason ie: 2zr swap, replacing the clutch etc.

If you autox then you would be able to benefit from the faster spin up since you're mostly in lower gears. That said, if you have the 2zr, pulling the tranny from underneath sucks so you're best to wait until you're already pulling the engine or need a new clutch.

One small thing I noticed and I don't know if it is specific to the flywheel or if I just started noticing it now. But under harder acceleration the engine make a quiet type of "whine" noise. Almost like a supercharger, but quieter. Might have nothing to do with the flywheel but I just started noticing it after I installed the flywheel.

I'll update this with any new info as I drive it more. Waiting on some dry weather to go for a "canyon" run (damn our lack of canyons)