project7s

iTrader: (5)

I just ordered an aluminum flywheel and which says itll be hard to drive. can anyone who has one on there car tell me what it'll be like and if it is really a horses butt to drive? thanks

j9fd3s

iTrader: (3)

in my experience it depends on the driver. i think the steel flywheel is what should come on the car from the factory, but if i give it to my friend he literally can't drive the car with a light flywheel.

there is some ratio of flywheel weight to car weight that works really well, imo, and this is kind of half baked, but i had an aluminum flywheel in a gsl-se for years and generally it was good but i thought it was just a little light. fast forward to now, and the same flywheel is in a really light 12A p port car and it feels stock.

so ymmv

project7s

iTrader: (5)

ok, its going in an sa with a 12a, and all the air conditioning removed and rb exshaust but its also still stock port. im not sure excactly how light this car is compared to yours.

Qingdao

iTrader: (3)

IMO I kinda dig on the heavy flywheel. This engine is lacking in the low end as is. I could only imagine how dead stop starts would be a bear without it. Engine revs up fast enough for my tastes; however, I've never drivin a light flywheel rotary.

project7s

iTrader: (5)

ive rode in a car that had a lightsteel flywheel though its a 4-port 13b and it was freakin awsome (which is the car that really got me into these) i just wonder if the aluminum will be too light and maybe burn up the clutch or something?

j9fd3s

iTrader: (3)

should be close? it'll be fun!

Kentetsu

I run a light steel flywheel. Can't hardly tell the difference (in driveability) from stock. Wish I had gone with the lighter option.

I think you'll be just fine...



.

Siraniko

iTrader: (13)

use an 81-82 flywheel, its only 21 lbs

t_g_farrell

iTrader: (1)

+1 on that.

I run an 82 flywheel, poor mans 12A light flywheel.

LizardFC

iTrader: (1)

I have a light flywheel in my vert FC. It's not a big deal. I can tell the difference between it and my other FC's... you just have to rev it up a bit more when you take off and make sure you are in a low gear going up hills. I imagine it'll have a bigger impact on a 12a but your driving will adjust and you'll enjoy the quicker rev.

PercentSevenC

I'm running an aluminum one now and an 8 lb. Greddy steel flywheel before that which was about the same. I don't even notice it anymore, even in traffic in downtown Seattle with its ridiculous hills. Actually, I find it annoying to drive cars with heavy flywheels now.

Granted, I have a 13B, but I used a light flywheel when I had a 12A, too, and it was no problem. You'll be fine once you get used to it.

Siraniko

iTrader: (13)

I have both aluminum and lightened steelflywheels. The problem is that it requires a higher RPM to get out of first gear and on a stop and go traffic, once RPM falls below 1k, you need to downshift from 2nd to 1st gear.

clubber

I have an alum in the maxton and it's great, it can be a bit much on hills but other than that, it's fantastic.

85rotarypower

I had a RB light steel flywheel on my 82 when I put the 13B 6 port in. Loved it with the HD matching clutch disk and pressure plate. Got to drive an RX-4 with a half bridge 13B this summer with an aluminum flywheel and I think a 6 puck clutch and that thing was a bear to drive by comparison. Clutch peddle feel was about the same as my 82 compared to the RX-4, but the engine would drop RPM's so fast it was hard to shift smoothly.

Looking for a lightweight steel flywheel for my 79 this winter. The stock one on the 79 is not very nice on the track since it is soooo heavy. Correct me if I'm wrong, but the 79 12a had the heaviest flywheel ever installed on a Mazda rotary and it shows. Makes for easy take offs but rev matching on a road course for downshifting requires a little too much attention, and if you get it wrong you know it.

On a side note I notice nobody really pays attention to how the weight is distributed around the flywheel, in relation to how far out from center the weight is. Even thought two 8 lb flywheels are the same physical weight, they may perform differently if more weight is out at the ring gear on one than the other. More mass further out from the center of the flywheel has more inertia which takes more power to accelerate and longer to decelerate. This is something that has kinda annoyed me about flywheel manufacturers as they don't specify where the weight is on the flywheel. You may think your getting an 8 lb but it may not actually perform any differently than a 13 lb because of how the weight is distributed.

rxtasy3

iTrader: (2)

no

notveryhappyjack

iTrader: (4)

I daily drive 9.5lb flywheel, my favorite performance mod.

You will get used to the feel, I can leave stop lights at 1,500rpm with no issues once I learned how to drive with it properly. Changing gears smoothly requires you to somewhat match revs or shift quickly.

In gridlock it might suck, but I can all but promise no one here builds their RX7 to sit in traffic anyways

clutch pedal feel comes from the pressure plate entirely, nothing else. Changing clutch disc or flywheel will not change how a clutch pedal feels when used

j9fd3s

iTrader: (3)

this is true, but 99% of us are just going to use one of the two RB flywheels, its only the hardcore 1% that are going to use something with a small diameter.

notveryhappyjack

iTrader: (4)

this is what I use, billet aluminum weighs 9.2lbs, fully serviceable friction disc, amazing piece of kit sold in 9.5 or 11 lbs versions

Jeff20B

iTrader: (13)

Yeah, I remember that^

The blue car got an RB light steel flywheel. The rotors are heavy R5 13B and this combination feels perfect. It should have come from the factory like this.

The GLC has an 8 pound Greddy steel flywheel. I recall it felt a bit weak/light on its first drive. I had two passengers and it was a fresh rebuild, go figure. Since then it received a new 2.5" exhaust and a Camden. The extra mass of the Camden should increase the rotating assembly's weight and make the flywheel "feel" heavier. Should be perfect. Fingers crossed.

The brown car is a GSL-SE. It has an RB light steel flywheel. It's got a Megasquirt that is untuned so it's hard to drive, but I think once it's tuned, it should work out ok. But if the flywheel feels too heavy, I've got a new RB aluminum in the MG that I could swap.

The MG has been test driven first with my REPU's engine, complete with the nasty 30 pound stock flywheel. That was unpleasant. Idle it up to 2k, let out the clutch, chirp the right rear tire without even trying. That can't be good for the stock rear. Later I tested the same engine with an RB light steel (currently in the brown car). This setup was a lot better. Then it became apparent what other problems the chassis had: PO built a crappy 1 7/8" single pipe exhaust so it limited high RPM. Also it had an NO intermediate plate and a reverse runner intake manifold (only mani that fits this chassis without resorting to passenger footwell mods). Reverse runner plus NO plate equals no secondaries! Primaries were amazing though. Then just recently I find out the carb I was using has some sort of problem opening the secondaries reliably. So three strikes against the setup that used the light steel flywheel. But like I said the primaries were amazing. I could have survived on them alone if I had to (they were that good).

MG 2.0 now consists of a purpose built 13B with sleeveless 3B housings ported nearly to T2 spec, Y plates ported to a mild streetport (half way between 74 spec and pineapple's big template) and an S4 NA rotating assembly. It also has an RB aluminum flywheel. Will the lighter rotors and lighter flywheel mess up the amazing primaries this car briefly had? Maybe. To combat this inevitability, I've planned out a complete long primary exhaust system to give back the low end torque lost by streetporting and hopefully cover for the lighter flywheel and somewhat tall rear end gearing as well. And on a whim I added a rare factory lightened dizzy drive gear and a lightened oil pump sprocket that I found in a pineapple racing engine. Anything to lighten the spinning mass, right? I even went as far as an aluminum underdrive pulley but later changed it when it meant I'd have to get a new belt. Plus I don't need to underdrive my waterpump. If I have to underdrive my alt, I have a couple larger diameter stock pullies from progressively older alternators, some that were internally regulated. This should give me enough options.

But of course the real proof is in actually driving this thing. To level the playing field, I will once again use the same weak secondary but awesome primary carb as before. We'll see how well I can live with just primaries only, amazing as they may be. Hopefully the better exhaust will let the secondaries flow like they should, or maybe I can dig into the carb to figure out what's going on. But wait! There's more! After the engine has had a chance to break in for while, and if the carb is available, I'd like to swap in an RB Holley 600. Now that would be some serious mojo. Or better yet the race prepped Nikki, if only I could make it fit under the hood. They're really tall for a carb.

peejay

The only problem with an aluminum flywheel is that if you have an engine like mine that wants to run buck-buck-buck-buck all the time because it was awesome ports, then you can't coast or cruise at low RPM because it will try to shake the drivetrain apart. If it had a massive heavy flywheel like stock then this damps out the shaking.

Flywheel weight has absolutely nothing to do with engine output at any speed, other than the engine's ability to accelerate the car. A lightweight flywheel makes this BETTER not worse.

IMO the flywheel should be just heavy enough to not self-destruct from clutch heat. I have the SR aluminum one, and I'd be happier if it weighed .95lb instead of 9.5lb!

If you have a stock port engine then put the lightest flywheel you can on it, YOU WILL LOVE IT. Well, you might not if you're one of those people who can't drive and engages the clutch completely before touching the accelerator, but McLeod might make a special 50lb flywheel for you to cover up your bad driving habits.