Traum Forged Piston set for J series Engines. Includes Pistons, Rings, Wrist Pins, & Clips.

89mm is the standard size piston for all J32 & J35 blocks.

Here is the estimated compression ratio based on matching Crankshaft & Rods.
Dish Top
J32 Crank & Rods = 9.2
J35 Crank & Rods = 9.85
J37 Crank & Rods = 10.15

Flat Top
J32 Crank & Rods = 9.9
J35 Crank & Rods = 10.6
J37 Crank & Rods = 10.9

Dome Top
J32 Crank & Rods = 10.8
J35 Crank & Rods = 11.75
J37 Crank & Rods = 12.1

Tall Dome Top
J32 Crank & Rods = 11.5
J35 Crank & Rods = 12.4
J37 Crank & Rods = 12.75