Thread: 1973 Buick 455/Stage 1 Conversion

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There were so many different iterations in those years, that I would refer you to the experts to answer your questions.....
TA Performance Products Inc. - Your Leader in Buick Automotive Parts and Accessories

I will help you with some of the terms so that you are on the same page with these guys.....

BLOCK DECK HEIGHT....The measured distance from the centerline of the main bearing bore to the flat part of the block where the heads bolt on.

PISTON COMPRESSION HEIGHT....The measured distance from the centerline of the piston wrist pin to the crown (flat part) of the piston just above the top piston ring.

PISTON DECK HEIGHT.... The measured distance from the crown of the piston to the deck of the cylinder block with the piston at top dead center. Piston deck height is added to the compressed thickness of the head gasket to determine squish (called quench by some, although quench normally refers to the cooling effect of the piston by transferring heat to the water jacket of the cylinder head when the piston is at or close to top dead center and close to the underside of the head). Squish refers to the "squishing" or "jetting" of the air/fuel mixture across the chamber as the piston closes in on the underside of the head. Squish tends to homogenize the air/fuel mixture so that you get a more complete burn of the mixture, thereby helping to prevent detonation.

As you study the 70's engines, you will find that the manufacturers lowered static compression ratio down into the 7's to help prevent detonation due to lack of squish being built into the motors.

DISH/DOME.... Pistons can be manufactured with a flat top (with valve reliefs) or with a dish to lower static compression ratio or with a dome to raise static compression ratio.

Buick played with differing sizes of dishes and piston compression heights in the 70's.

Here's some hard data.....
https://www.teambuick.com/forums/vie...5_engine_specs

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