Looking at my 454 that sits in my 68 I noticed there appears to be no external balancing on the balancer and when I yanked the flywheel I did not see any balancing on that either. I've driven the car for maybe a half hour before winter but with a top speed of maybe only 35mph. Is there a chance this engine doesn't need the external balancing or is there a way to balance the damn thing without yanking the motor? I have no line of communication to the owner before the dealership so I don't know whats really in it.
Help is appreciated...I can't handle any more suprises...nor can my wallet.

 

You sure it's a 454?

 

GM internally balance thier performance engines till like 70, if this is a 70 454, then it is possible, but check the castiong number to be sure . do you know where ther negine came from ?


tim

 

Block # 361959 Engine VIN: C9Z209270
All the research that i've done tells me its a late 70's 454 light duty truck block. Not a tall block. When I removed the flywheel the rear of the block said "PERF" which agreed to a few other members 454's. Owner before the dealership must have replaced the block.
The way this car was jury-rigged Bubba could have done just about anything. How would I know if the engine was out of balance? Would it shake on startup or would i have to get it up to a high speed? Does an engine shop have to pull the engine to balance it?

 

previous owner prolly installed the 3.76" stroke crank (427) and the 427 balancer and flywheel..if that's the case you have a 427, not a 454

OR

The previous owner installed an internal balanced 4" crank, used the 427 balancer and wheel, if that's the case you have a 454

 

Is the car an original Big Block car? If so it may have went like this. Bubba blew up his 427 motor. Put in a later model big block and reused the balancer and flywheel that was on the 427 originally not knowing that the original was internally balanced and the new motor was externally balanced. Easy error for someone without a lot of knowledge (Bubba). I would think you would notice some vibration. You need to fix it as it will eat the main bearings. If you have to change the flywheel anyway probably want to pull it and have it checked out. Or just put a later balancer and flywheel on it. Or drive it till it goes and drop in a 502. Another option is find a correct date and casting # block and build a short block for it. If the heads, intake, carb, pulleys, accessories, Ect are correct I would go this route. The balance can't be checked in the car. See if there is anyway to do a title search at your DMV to find Bubba and ask him what you got as maybe George is right and just the block was changed but usually if the block is unusable the thing grenaded so the crank and internal components are done.

 

yeah that sounds about right.... The only thing i would add, is that if you are willing to yank the motor and want to keep it having the rotating assembly balanced is always a good idea

otherwise go hunting for the balancer and flywheel for that block on the aftermarket, and that will at least get you close