Flywheel Help !! Options

[salman2510]

So Guys Here Is Where I Need Your Help, I Ordered The Jun Ultra Light Flywheel, But For Some Reason The Transaction Didnt Go Through.

In The Mean Time I Spoke To A Few Other Guys Who Has Highly Modded Cars, Some Say Fidanza, Some Say To Go For Spec, The Others Say To Get The Jun !!

So Guys What Do You All Think Which 1 Should I Get ??

Moreover I Have A 3sge Gearbox And Finding A After Market Or Light Weight 3sge 2nd Or 3rd Gen Flywheel Is Like Looking For Pamela Anderson In Bedroom !!

The Clutch Spec Is 225mm 20 Splines !!

So Will A 3sfe Or 5sfe Flywheel Fit A 3sge ?? Are The Bolt Patterns Same ??

Thanks Guys

Regards

Salman

[BonzaiCelica]

Ok, let's break it down to basics...

Mass = Inertia

Inertia = Resistance to motion change

If you have more mass, you have more inertia... and therefore more resistance to change in motion. Objects with more inertia require more force to change their direction/speed/motion than objects of lower inertia.

In the case of the heavy flywheel, that's more resistance to acceleration as well as deceleration. When your engine is spinning in neutral and you engage the clutch to start moving, the flywheel helps your engine overcome the added load of the car's mass... effectively, the inertia of the flywheel (spinning) helps to overcome the inertia of the car (sitting still, not wanting to move). If your flywheel weighs 20 pounds and your car weighs 2000 pounds, you can see that a 20 pound flywheel will help to move the car better than a 10 pound flywheel will. It resists the change in motion that the car is imparting upon it more than the lighter flywheel, so it will require less input from the engine, and start the car moving along a bit smoother.

Analogy:

Ever go bowling? Compare an 8 pound bowling ball to a 16 pound bowling ball. The 8 pounder is easier to accelerate (from the stopped position to you throwing the ball at higher speed) and easier to direct (aim). Your arm also gets less tired with the 8 pound ball. The drawback is that the ball loses more speed toward the end of the bowling lane, and may not knock down as many pins as you want. You also have to be more careful with controlling the direction of the ball, since it's easier to fling out the wrong way if your arm twitches or something The 16 pound bowling ball is harder to accelerate and harder to direct, but it carries more speed at the end of the bowling lane because of its higher mass (and resulting higher inertia). It knocks more pins down. It's also harder to send the ball careening into someone else's bowling lane, because it's harder for your arm to suddenly jerk it to the side.

Now relate this analogy to a car... the pins at the end represent your car's weight/mass, the bowling ball is the flywheel, and your arm is the engine. The lighter flywheel will be easier to accelerate and decelerate- so you'll have quicker starts, faster acceleration because the flywheel has less inertia to overcome, and quicker shifts because the revs drop faster when you let off the throttle. The downside is that you have to control the flywheel more, since the direction (speed of rotation) varies that much more. This is why people say that an "8 pound flywheel isn't good for a daily driver". I don't have any problem driving with mine. The heavier flywheel has higher inertia than the lighter one, so it will start your car from a stop more easily (knock down more pins), but it will hurt you everywhere else. It takes more force/power to accelerate (overcoming more inertia), doesn't allow you to shift as quickly (revs don't drop fast enough), but it is easier to drive because the speed of rotation doesn't change as rapidly as the lighter flywheel. Small changes in your throttle position don't change the revs as much, because the power blips are just soaked up in the heavier flywheel. This is why people might think that "a lighter flywheel takes more gas while cruising", because that lighter flywheel takes more attention at the gas pedal than the heavier one to maintain speed. The lighter flywheel will give you better gas mileage.. ever push that 8 pound bowling ball on the ground at a constant speed? Now try the 16 pounder- which one takes more energy to push? The 16 pounder. It's the same as the flywheel.

Do you lose torque with the lighter flywheel? Yes and no. You lose torque to start the car moving, since less energy is stored in the flywheel- so you have to apply more torque from the engine. On the other hand, you use less torque to overcome the inertia of the flywheel while accelerating and decelerating, so you can use the torque from your engine more effectively. You don't lose any torque when going to a lighter flywheel- you just change the source and application of torque in your car's drivetrain.

So...

Light flywheel: better acceleration, better mileage, takes more skill to drive
Heavy flywheel: worse acceleration, lower mileage, takes less skill to drive

It's that simple.