Crankshaft harmonics?

[art leong]

Originally Posted by SSDiv6

Art, running a solid metal pulley is a recipe for disaster on a high RPM 4 cylinder engine, especially if you do not have counterweights and no dampening.

Here is a link with some good discussion on the subject:

http://www.eng-tips.com/viewthread.cfm?qid=107602

It's just that there are hundreds if not thousands of people running the same block and crank setup. Most are street cars and they use the aluminum pulley to underdrive the alternator. When racing they shift at the same rpms as I do (within 500 rpms). A lot make twice the power I make and three times the torque.
The one substantial difference is they are turbocharged. And I have to extract as much power as I can because of my lack of pressureized air.
I ran a crank with the counterweights removed. I'm starting to see that most if not all of my problems since I put this motor in the car. Might be traced back to the harmonics. My first problem was a broken stator support in the trans. Another problem that nobody that runs automatics and these motors had ever heard of.
The first motor I built was a mild (get to know the combo) verision. It ran trouble free for 2 years. And when I wanted to go fast it was shifted at the same rpms. With over 200 runs (a lot with improper fuel mixtures) the bearings looked like the day I built the car.
With the new motor the bearings allways looked weird (like there were oiling issues) in places that should not show issues. This was verified by this this time the rod bearings had only one easy run.