engine balance... please help!!!!!

[brettlanphere]

hi. i have a 331 stroker that was built by an AWESOME engine builder in chicago. i know for sure that he balanced the crank by itself... i have an aluminum fidanza flywheel. he told me to add 28 oz weight to the flywheel and marked the spot. i did that. i ran the car a while then it sat for two years... i got it running again the other day.. now i have a HORRIBLE vibration at high rpm in all gears, even in neutral with the cltch pushed in. based on what i have read online when the crank is balanced seperate you add a zero offset balancer and flywheel... so now im confused. should i have added weight to the flyhweel or not? and what kind of balancer do i need o buy? zero offset, 28 offset or 50? i know this vibration has to go or it will tear up my expensive engine. i really really need some help with this.. hope you guys can help out

 

[toyman]

I would get back to the builder. He's the one person that can give you the correct answer to your questions.

 

[ProKiller]

the balancer and flywheel have to be balanced the same. so if he told you to put a 28 oz flywheel on then you need to verify that and and the HB is also 28oz. But like Richard said, check with him before you start taking stuff apart.

 

[revhead347]

Most stroker cranks build today are internal balance. It's possible, but unlikely you have a 28oz imbalance crankshaft. The most important thing is that the harmonic balancer is also a 50oz imbalance.

Kurt

 

[brettlanphere]

i got it resloved. thanks for your input. the engine was balanced to 28 ounces so i had to swap out the harmonic balancer. put a 28 ounce balancer and now its smooth as can be. thanks again for your help