Are they balanced the same? since there are new rods I am "fearing" they are balanced differently.

Chris

[This message has been edited by eph_kay (edited 12-28-2009).]

I guess I can elaborate more too, I just installed a series 2 flywheel on my series 3 engine, and finally got it started and there are significant vibrations coming from the engine, like shaking stuff off the car that was sitting on the trunk rim.

I don't remember from putting the flywheel on, but I am thinking, if it is possible, I either put it on rotated, so the balance doesn't line up, or the internals aren't balanced the same.

Chris

I believe the L67 flex plates are all ballanced to the specific engine they came off of; I could be wrong.

As for the flywheel going on wrong, there is one oblonged hole on the flywheel that lines up with a hole that is out of the pattern of the other holes. I dont think you can get all eight bolts in without that hole being lined up with the oblonged hole; but again, I could be wrong.

Doesn't it matter whether the engine is S/C or N/A ? I thought the N/A was internally balanced.

The n/a's are internally balanced, and the s/c ones are externally, and I am pretty sure I remember now when i put the flywheel on that I saw the "odd" bolt hole, I think I questioned myself then too about getting it on right. I am pretty sure all the l67s are balanced the same, you can buy a premade aftermarket flexplate and I am pretty sure you don't have to send in your flexplate to get it balanced too. If it comes down to it, I will pull the engine again and take the tranny off and take it to get balanced, if I can find a place that does it... But from what I am reading they seam to be balanced the same.

Chris

quote Originally posted by weaselbeak: Doesn't it matter whether the engine is S/C or N/A ? I thought the N/A was internally balanced.

BOTH the SC and N/A versions of these engines are EXTERNALLY balanced. The amount of balance differs between SC and N/A engines for both the harmonic balancer and the flywheel/flexplate.

There is NO 3800 Series 2 or 3 engine that is 100% internally balanced.

-ryan

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6+ years on this same swap -- NO engine or transmission failures...

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