Volume of valve reliefs in stock pistons
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From: Tucson - MdFormula350 = Post uberWhore
Car: Sexy
Engine: Stock
Transmission: Slipping
Volume of valve reliefs in stock pistons
I'm trying to figure out compression ratio of a set of AFR's I'm looking at and I need to know the volume of the valve reliefs in the stock pistons for a 1990 L98 engine. I've heard 4ccs and also 6ccs.
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From: Houston, Texas
Car: 1989 GTA Nighthawk
Engine: 389 CID TPI
Transmission: TCI 700R4
Axle/Gears: 9 bolt 3.23
It shouldn't matter. If you are putting heads on with the same combustion chamber cc then the compression ratio remains the same. If not just compensate for the difference in chamber volume and any difference in head gasket thickness.
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The stock 350 pistons I have measured (syringe and trans oil) have netted 4.5cc for all four flycut valve depressions, or about 1cc each. The dished pistons only have about 2cc total for all four depressions, but they are not cut as far below the piston top due to the dish.
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