Wouldn't weighted flywheels beneit our low-torque cars more?

[Loser_guy]

From what I understand of the physics of an engine (given all that I kow is self-taught from doing a ton of work to my motorcycles) the flywheel gives the engine the momentum to keep turning..

I guess I'm just wondering how the lighter flywheels would benefit our cars, other than a quicker neutral rev due to lesser inertia.

Wouldn't a slightly heavier flywheel increase torque, and also make shifting into lift (for us gt-s guys) easier since the internals would have more rotational mass pushing them, leading to the motor 'revving-down' slower? Or is my logic totally screwed up?

I put a flywheel weight on my KTM 85 because I needed to be able to climb hills without being in the powerband, man did it make a world of difference.

Sorry if this seems like a noob question, strange thoughts come to my mind when I can't sleep.

[Ryude]

Well the lighter flywheel is part of the gearing equation, thus the lighter it is the easier the engine can turn the wheels. The same reason people use underdrive pulleys, or get lightened crankshafts etc.

[Loser_guy]

Originally Posted by Ryude

Well the lighter flywheel is part of the gearing equation, thus the lighter it is the easier the engine can turn the wheels. The same reason people use underdrive pulleys, or get lightened crankshafts etc.

I see, so it basically helps acceleration, and potentially fuel mileage?

[danGTS]

but would it hurt torque then? It is no the first time I heard of weighted FW ..

[Ryude]

There is a very very complicating formula for figuring out just how much of a difference it makes. With a guesstimate, I would say 200 lb reduction in first gear, 100 lb in second, and alot less in the following. You also get like 2-3whp since your car uses less energy to move it.

So it technically gives you a tenth or two ET. Not bad for about $300.

[Celicasaur]

i dunno man. my fidanza wheel and UR crank pulley combo have made a world of difference. sure it doesn't feel any more powerful, but the revs climb up a LOT quicker (you need a month or so after an ecu reset for this to happen though, ive noticed) and the throttle response is fantastic. surely more power mods like a header etc will make the lightened parts turn even more quicker than on a stock flywheel.

[jayspeedy24]

^^^ thats what i want to hear! i got my header coming in within the next few weeks and my flywheel is about to be ordered...i doubt im going to be dissapointed in it..i've never moved beyond i/e so my car will feel awesome when its all done.

[LEDmod]

Our car is design to high-rev and stay on higher rpm.. so I would say it doesn't benefit for weighted flywheel...
For drag race, might be disadvantage....

[slidr]

Originally Posted by Dooly

Our car is design to high-rev and stay on higher rpm.. so I would say it doesn't benefit for weighted flywheel...
For drag race, might be disadvantage....

Actually, if you wanted your car to stay at a higher RPM while shifting, a weighted flywheel would help that.

[00gtsGETemHIGH]

Originally Posted by slidr

Actually, if you wanted your car to stay at a higher RPM while shifting, a weighted flywheel would help that.

Originally Posted by slidr

Actually, if you wanted your car to stay at a higher RPM while shifting, a weighted flywheel would help that.

i think so too.. i just got the flywheel and i'm still shifting like a granma.. just because i want to break the clutch in properly.. and my linkages are a little loose.

anyways, a heavier flywheel will take longer to decelerate staying in higher rpms longer....thus making the 1-2 shift in lift easier....

[LEDmod]

Originally Posted by slidr

Actually, if you wanted your car to stay at a higher RPM while shifting, a weighted flywheel would help that.

If know how to drive the car, you won't have problem staying at higher RPM while shifting....

[jst07]

Originally Posted by Dooly

If know how to drive the car, you won't have problem staying at higher RPM while shifting....

And the weighted flywheel is robbing you of power too. The only time a weighted flywheel is good is in a turbo setup, where you want it to stay spooled between shifts.

[MidNite]

So then it sounds like for AutoX it will help keep the rpms high, but hurt drag times because it would take away from acceleration.

[Celicasaur]

actually this is a myth that the revs drop much quicker during gear shifts.perhaps some day i'll make a video for you guys.

also, it doesnt matter if your gearshifting is as quick as 0.1 miliseconds, when you get out of first gear at 8200, the car will land at 5800 in second gear - to stay in lift you must rev match and apply at least 2 thirds of throttle and then feed in the clutch. Since ive had my fidanza 'wheel i find this process MUCH easier because the revs shoot up there so much quicker. just a shame i cant do the gear change any quicker because my second gear synchros are soon to die.

[Ryude]

Just get a PFC and raise your rev limit or lower your lift point...easy fix.

And... I have 8100 rpm limit and land 6000 in 2nd gear without powershifting.

[Celicasaur]

Originally Posted by Ryude

Just get a PFC and raise your rev limit or lower your lift point...easy fix.

And... I have 8100 rpm limit and land 6000 in 2nd gear without powershifting.

man, im looking forward to that day for i get one! then i dont have to drive so vigorously to make it fly!

[00gtsGETemHIGH]

Originally Posted by Celicasaur

actually this is a myth that the revs drop much quicker during gear shifts.perhaps some day i'll make a video for you guys.

also, it doesnt matter if your gearshifting is as quick as 0.1 miliseconds, when you get out of first gear at 8200, the car will land at 5800 in second gear - to stay in lift you must rev match and apply at least 2 thirds of throttle and then feed in the clutch. Since ive had my fidanza 'wheel i find this process MUCH easier because the revs shoot up there so much quicker. just a shame i cant do the gear change any quicker because my second gear synchros are soon to die.

it's good to know that slipping the clutch will still let you land the 1-2 shift in lift.
once i break it in, i'll try it.