Ballance Percent???

[blue t-type]

I am haveing a 3.8L turbo engine ballanced at my local machiene shop. I have herd of 2 different ballance percent specifications used on the 90 degree Buick v6 engines. 36.6% and 50% What is recomended for a Turbo Buick?

Adam

 

[blown okie]

50% imo.

 

[turbodave231]

Balancing the reciprocating asembly at 36.6% puts the natural imbalance in the horizontal plane. The stock rubber motor mounts can easily absorb the movement. Balancing at 50% moves the imbalance in a vertical plane which is OK for a racecar with solid motor mounts or engine plates, but not good for a street driven vehicles.

If you are using a stock crank go with 36.6%, Forged or billet crank go 50%
You will also need a neutral balance dampner and flywheel for the 50% internal balance route.

Dave

 

[norbs]

My stock crank is balanced at 50% and its not bad There is a slight vibration at 2000 rpm but at high rpm its silky smooth. This required mallory weight and alot of it in the crank, cost me about $350 to balance the crank alone. I stayed away from the poly mounts to stop any more vibration from being transmitted in the car.

Now i have a billet crank balanced at 36.6 becasue the shop crankshaft specialists in , TN made the crank wrong and took too much weight out of the counter weights, there mistake, and my empty wallet. I will not deal with them again ever. Sorry for the rant.