balance?

[nj12sec]

i'm putting together a 600awhp setup... some say i'm crazy for running a new stock crank pulley and resufaced original stock flywheel. should i have the motor balanced? see the motor was balanced but with an unorthodox crank pulley and ssg aluminum flywheel. these two parts were stolen. the crank is also stock. eagle rods, wiseco pistons. think i'll be ok with stock balance?

 

[Maglin]

You're not crazy for wanting to run a heavy flywheel and stock crank pulley on a 600 HP motor. Sounds to me like you want to kept your crank since those two components are key to dampining crank breaking vibrations. Yes you should be ok. Usually the bottom end is balanced together seperate from the flywheel and harmonic balancer.

 

[Big Woo]

Every rotating engine part should be neutral balanced separately. Find a shop that will balance the crank, then add the harmonic balancer/front pulley, and the flywheel, then balance again, then add the pressure plate and balance it. Many people will forget about the pressure plate, but it is a fairly heavy, large diameter rotating part.

When the crank is being balanced material should be removed or added to the crank to obtain a neutral balance. When the other parts are added (flywheel/ pulley, etc.) the material removed should come from the component being balanced. The end result being that all parts are individually neutral balanced. Thereby if a part needs to be changed out later, it to can be neutral balanced and added without effecting the existing engine balance.

This form of balancing should not be confused with balancing the entire assembly as one, as in this type of balancing the sum, and radii of the out of balances, can both counter act, and accentuate, dynamic, and kinetic balance at opposite ends of the assembly.

Some will say there are levels of balance, in my opinion, it is either balanced or it is not balanced.

If you are looking for 600 whp, you should definitely have the engine balanced.