Light weight flywheel - good idea?

[mylesdw]

Originally Posted by 914fan

The flywheel weight affects cruising more than anything.
<snip>
With a heavier flywheel you can cruise using less fuel.

I disagree; at a steady speed the weight of the flywheel is virtually irrelevant and will have an insignificant effect on fuel consumption.

Removing weight from the flywheel is exactly the same as removing weight from any part of the car except that gearing comes into account so that removing 1 lb from the flywheel is equivalent to removing around 15 lbs from the body weight (in first gear). The effect is the same; it allows the car to accelerate faster for a given force applied.

[DAVID GAGNARD]

I've been driving a 3200 lb 65 Mustang since 1995, it has a 35 lb. steel flywheel and a 350hp 351-W...........test drove my road race car this past week, 331 cu in, 472 hp, 15 lb aluminum flywheel and light weight where ever I could in the driveline, have not wieghed the car yet, but it should come in around 2600lb or a little less, at 3000 rpms in forth gear I steady gave it the gas till it was 80% full throttle and in a few seconds I let off cause I thought the clutch was slipping, that's how fast the rpms came up, did it again a few times with the same result, but then I have never driven anything like this before and was used to a lot less hp and heavier rotating mass..........that thing winds up realllllllllllll fast and no doubt the alum. flywheel along with a few other light weight components made the difference...............

David