"Lightened Flywheel", Anyone ever heard of this? Options

[m170seeker]

I just had the flywheel changed on my 74 2.0L 914. Mechanic said the old flywheel was a "lightened" one and my new one is stock. I'm curious about you all's opinions on the difference; pros and cons of each. Apparently the PO decided to go for more high end acceleration than low end? I've never seen anything about this on the forum.

[Brodie]

aircooledtechguy is right on. I've lightened flywheels for dirt track racers in the past. They say it helps acceleration because it doesn't take as much to spin a light flywheel as it would a heavy one. Flywheels store energy so once up to a steady cruising speed it takes more to slow down a heavy flywheel than a light one. That generally will give you better MPG because the engine doesn't have to work as hard because the momentum of the flywheel keeps the engine turning. One has to be carefull about weakening the flywheel if you take too much off of it. There is a fair amount of pressure on the flywheel.