Whats the good & bad points to a lighter flywheel?

Hi all Just curious on what you think , the pros and cons of a lighter flywheel. Other then the obvious power gain , was it worth to you, would you do it again ect ect...Thanks

what power gain?

Reduced rotational mass uses less energy to accelerate something. So the effect is a net power gain.

Yeah I know, but it's gotta be a minimal gain/benefit on a street car. I doubt much more than a couple of ponies at best. I wouldn't plan on a massive, seat of your pants, double digit hp gain is what I was alluding to with my slightly sarcastic question.

better throttle response - no real power gain - better modulation of the throttle - good for a track car. unless you need a new flywheel and are willing to put up with the possible stalling issues (996 is less prone to BTW) and it's a street car - Why do it? Seems like a lot of $ of minimal gain easier ways to drop weight and increase throttle response (most chips do - different method and result of course)

OK Sorry Chris , Not power gain, but the car has way better throttle response ,revs much faster, and less rotating mass is hugh.. it acclerates mush faster. I will never go back to a stocker, I just wanted to hear what others thought.I have never had a issue staling but I must admit it is a bit noisy.

I guess what hasn't been said is that it allows your engine to spin up faster but it also looses rpms faster when you lift. Some like it on the street but others find it makes the car more difficult to drive. The bad news is that it's pretty expensive to find out which camp you are in. I've driven a student's 996 with one and it does make a significant difference but, as has been mentioned, not as much as older 911s. I'm not sure why. Jim

It is amazing what a reduction in moment of inertia will do to a spinning mass like the Flywheel. The dirver immeadiatley feels a difference and all things considered the manufaturer could easily say you have more HP, you would assume so from the way the car feels. But Physics tells us the reduction in mass is somewhat equal to a reduction of overall chassis wieght. Best regards

I had to replace my dual mass flywheel on my RSA--it broke. I replaced it with a cup one piece flywheel. The "translation" (my word) of power from the flywheel to the rear wheels made a difference in the increased performance. As I understand it, the hp at the flywheel didn't change, but the hp at the wheels increased...but, if I were coming to a stop with the a/c on (used both for street and track), the tach would "hunt" for a bit and sometimes stall. This I understand was a common problem with the change made on a 964--it might not be for a 996, but I'd check this out thoroughly before doing this.

When you say "much faster"... are we talking a full second or even 1/2 second on the quarter mile? Apparently there is a flywheel that is lighter and makes *no noise* can't recall what it is... I recently did my clutch and opted not to do the mod because of the noise... what about the car on the highway... I hear it slows down much faster as well so your always on and off the throttle to maintain desired speed... if this is the case then I would think gas mileage is gonna suffer no?

Hey kilrgt, I have done this. Personally speaking, I love'd it. The throttle response was absolutely perfect. Rev's were quick and precise. You lose a little weight from the car (always a benefit) and you do transfer a tiny amount of power to ground. With the rotation mass of the fly reduced the only gain is a nominal 2-5hp. HOWEVER, the reduction in flywheel speed is greatly felt when drving aggressively or on the track. If you track the car, this is a great mod. Drawbacks: Lightweight flywheels often cause a "chatter". While they are properly balanced, they will appear noisey due to the change in weight. It's not bad. I got used to it pretty quickly. Good luck. My vote would be yes!! Just my .02. Chad