Durango Deuce Engine Parts VII
Piston weights
These are several 4" bore pistons that could be used in the 327.

The first one is the JE I plan on using; the second is a new TRW cast piston; the third is the production 327 piston (std.)  and the last is the "Bowling Ball" TRW forged piston originally selected.
The TRW pistons are commonly used in most "Hi-Po" rebuild kits. Durable, but heavy. Even though I had a block that was bored and honed for these, the added weight would be a disadvantage for road racing. The constant acceleration and de-acceleration favors a light weight reciprocating assembly.
I'm using 4.030" Forged JE Pistons with a 1.425" compression height. This piston is for a 350 engine with a 3.750" crank and 5.7" rods (Chevy 383)
This piston will also fit a 327 with a 5.94" to 6" rod as long as I pay close attention to block and deck height and gasket thickness selected.

DECK HEIGHT CALCULATION

((Stroke / 2) + rod length + compression height) - Block height  = Deck height

(3.25 / 2) + 6.000 + 1.425 = 9.05

9.025" - 9.05" = -.025" deck height (piston above the block deck)

Using a 6" rod would mean milling some material off the piston top and / or using a thick head gasket.

A 5.94"
L-99 rod (pn 10108697) would give us a +.026" deck height (Piston below the deck)
Milling .010" off the block and then using a .022" head gasket would be just about right with this rod. This rod is supposedly good for 450 hp, but would have to be bushed for the full floating piston pins.

Proper
Quench dimension is critical. Obviously we don't want to smack the pistons into the head, but we need to try to get the distance between the head and the piston at TDC in the  .035" to .045" range. This will help reduce any tendency to detonate and improve VE.

Head gaskets are available with compressed thickness from .016" to .051". Steel shim gaskets are available  (.016", .018" and .022") that can be used separately or stacked to get desired height.

I'll be mocking up the pistons, rods, gaskets and taking many measurements before making my final selections.

The piston was ordered with a 1/16", 1/16", 3/16" ring package to reduce drag. This is worth about 10 HP at 6,000 rpm. I plan on using
Total Seal rings to improve long term leak down.

These pistons are made from unique left and right forgings to minimize weight without sacrificing durability.  Compared to the TRW forged pistons, the JE will save 223.5 grams -
each.
Multiply by eight pistons and convert to pounds gives us a whopping 3.94 lbs removed from the reciprocating weight!
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