I am not to sure where to post this but i guess i will start here. I finally got my car running the other day after installing the fast xfi unit. the car sat for over a year before finishing the install. Durring this time i also replaced the clutch (mcleod street twin) and flywheel. I have a stroker motor and i purchased a external balanced flywheel at first. I started the car and i had a vibration at around 3k. I than relized that i had the wrong flywheel and than purchased an internal balanced one. Well the vibration is still there and its pretty nasty. What else could cause a viberation. Nothing else is different except for the clutch and flywheel set up. Do stroker motors take a different kind of flywheel??

 

anyone??

 

Thanks anyway. i found out what the problem was. Thanks again

 

So how did you solve your vibration problem?
I have the same problem with my 305.

I had bought a external flywheel before I even knew there was a difference between internal and external. GM performance cataloge has a note that engines with one piece rear seals need an external flywheel (#14088646 or #14088650). Look up the same GM performance flywheels on Summit's and Jegs website and they list them as Internal balanced. Who's right?

Just this week I bought the light weight GM performance flywheel from Summit and I am in the process of installing it now, but I don't know if it will solve my vibration or not until I get it all back together.