[RICK LAKE]

FUNFER2 Kevin what the flywheel is made of doesn't matter unless you are looking at a certain application. As stated, a 40# flywheel has more stored energy that a #20 flywheel. This is great to get 3,500 lbs car or trucks moving. With 2,500lb cobras, DEPENDING on the motor torque and power range, you don't need this. Some of the guys on here are running complete multi disc setups that weight 22 lbs. like Nascar. High HP low torque production motors. This is why nascar guys leaving the pits do burnouts all the time to clean the new tires and also saves the clutch from glazing.
Mike didn't say what his trans ratios are or the rearend ratio. The problem if the clutch disc and the air gap getting smaller are the riding of the clutch pedal. Clutches like to be either fully engaged or fully released. Riding glazes both plate and flywheel surface. Over time will warp and give hot spots on the flywheel surface. It sound like he has a motor with a large camshaft and a rough idle. His motor makes it's power higher up on the rpm scale. The size or how many carbs are on the motor is not as important as the low end torque numbers. IMO Mike needs to either change the power bands in the motor( lower with a camshaft change ) or get a taller trans mission ratios in the 1st and 2nd gear. This way the motor will be able to run better ( in the rpm range it needs ) and he wouldn't have to ride the clutch pedal in and out to make the car move at low speed.
Aluminum flywheels do have inserts that are steel or iron. They are also rebuildable on some units. If you build a torque motor, using a #20 flywheel will kill some of the low end power in a lite car. This helps to get off the line without blowing the tires away. A high rpm motor also use lite flywheels with there 6,000 rpm launches. It's about matching parts to work togeather and get the best over all performance, drivibility, mpg, and enjoyment.