I gladly discovered that the car was equipped with a 455.
you know what the quick visual id is between a 350 ( 6 bolt rocker covers ) and 455 / 430 / 400 ( 5 bolt rocker covers )? many people confuse the two engines, don't ever go by the air cleaner. they are almost identical deck heights and widths.
if you have a big block, the displacement will be cast into the top of the trans saddle at the back of the block.
I would like to know how to tell what year the motor is
the simple way is to find the two letter Engine Code or the nine (?) digit Engine Identification Number ( which is an abbreviated version of your VIN ). these numbers should be stamped into the drivers side deck of the block, if the block has been decked they'll be gone. a wire brush, brake clean or gas and some chalk can all be helpful when trying to find old numbers.
the two letter code is the best thing to find as it's the most specific about what the engine configuration was.
and if Its a GS or GSX motor or a motor of some value.
GS and GSX don't have anything to do with the motor, they're trim and handling packages depending on the year. hell, the 74 Buick Apollo had a GS option with a six cylinder engine.
what you're looking for is a Stage 1 455 engine, this will be coded in the two letter engine code. all the other major identifying parts of a Stage 1 are internal. the biggest thing is the oversize valves but you won't be able to verify those without pulling the heads. Stage engines also have more aggressive cams but modern cam grinds are much better anyways.
ask him if he bought any parts from TA Performance, they're in Scottsdale.
How would I be able to identify what kind of rear end It has.
there should be a two or three letter code stamped ( i think ) on the front of the drivers side axle tube. that's assuming the rear is stock.
something like 'LTB' would be an 8 1/2" ring gear ( good because you can use Chevy gear sets ) with 2.56 gears and posi from the Buick factory.
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