lynwood78

How much torque increased am I expecting here from swap the factory steel ?

moosestang

I'm not going to bother with an aluminum flywheel. I don't think the cost is worth the gain. Plus I know I read that a steel flywheelholds up better to abuse.

CLUBSFIT

Here, I dont know exact #'s but I had an aluminum flywheel in my supercharged 350Z, and I autocrossed, dragged, and it other than my blower was the best mod ever! So fun tossing through the gears, but it made the car harder to drive daily. The RPMs dropped like a stone!! A good flywheel will stand up to whatever you do to it!! Just do it

androdz

Remember a aluminium flywheel will give you better low end but it will surely kill your top end.

Andrew

CrazyAl

Where is that information coming from?


An aluminum flywheel is lighter than a steel one. This means it takes less energy to spin. Just like a lightweight driveshaft or lightweight wheels, it means that when you accelerate you are transferring more HP to the ground instead of spinning parts on the car. A side benefit is that when you push in the clutch to downshift, the engine RPMs will drop faster. But when you are accelerating, top end or bottom end, you are gaining HP to the wheels. In fact, if anything the gain is BETTER at the top end becasue that is where the inertial losses are highest.

The downside is that the engine has less inertia to keep it going at idle. So, if you aren't very good with the clutch it is easier to stall the engine when you are starting from a stop. But given how much torque these motors have that is not much of a concern.

Norm Peterson

Actually, an aluminum flywheel only hurts you whenyou're starting from a dead stop, because it stores less energy in the form of rotational momentum. But once the clutch is fully engaged, the lower rotational inertia means that more of the available engine torque goes toward accelerating the car (it doesn't create any torque that wasn't there before; it only lets your car's straight line accelerationhave the use of more of what is there). At all speeds up to top speed. Conversely, you'll have more compression braking in gear and the engine revs will drop off much more rapidly in neutral as well. Top speed won't change, because as you get there, acceleration drops off to zero, meaning that the effect of rotational inertia will be zero (the "torque = [Rotational Inertia] * [Angular acceleration]" term effectivelydrops out leaving you with engine torque only needing to balance the total drag). You'll get up there quicker, but you won't be going any faster.

Edit#2: flywheel inertiaeffects are the greatest in first gear, and progressively drop off as you go up through the gears.

Simple physics.


Norm

likemike99

nice explanation guys. any makes you recomend? or would stay away from?

Fast Toys

We have been using and selling Spec Aluminum flywheels for years. We highly recommend them. It is quite noticeable that the engine revs quicker too

The Spec sale we are running right now includes 10 % off their flywheels as well

androdz

When my dad put a flywheel into his old fox body he had a friend with a turbo 3.6 that was really really close to him thru all the gears. When he went with a lighter flywheel he would pull on the low end and on the high end the 3.6 would catch up. Conversely when they acelerated @ 80mph the 3.6 would pull out around 2-3 lenghts when they were dead even before. I heard the mechanic saying something about the rotational weight of the flywheel vs the wind resistance. Let me look up on it and I will see what I can find

Andrew

Feng Houzi

so aluminum driveshaft and flywheel = good combination?