EJ25 - PLATINUM SERIES TURBO TUFF PISTONS 
 
57cc B25 Casting (04-06 USDM STi)      57cc chamber.
51cc D25 Casting (06-07 USDM WRX)   50cc chamber.
S20 casting (02-05 USDM WRX)   49.5cc chamber.
 
The best aftermarket Subaru piston company just got even better with our new Turbo Tuff lineup targeted specifically for EJ25 engines. By incorporating proven design enhancements from our "Formula-Won" piston forging, we've created the ultimate Subi piston to withstand the rigors of the highest boosted and stressed applications yet still run "quietly" and trouble-free for the daily driver. Like all Manley Subaru pistons, these are made from 2618 alloy, utilize an offset wrist pin design, are skirt coated and include our standard 2.500" x .180" wall premium chrome moly wrist pin (P/N 42346). 9310 alloy .250" wall pin upgrades are available. Simply order the EXTREME DUTY part number in the column below. These come equipped with the 9310 pins (P/N 42547). Premium steel top rings with Napier style second rings and higher tension oil rings for ultimate oil control are included with each set along with round wire locks. Recommended clearance: .003" for mildly boosted and .0035" for highly boosted measured .850" (79/83mm Strokes) and 1.100" (75mm Stroke) from the bottom of the oil ring groove.
Manley Subaru EJ257 pistons now include Napier style second rings and higher tension oil rings (by Total Seal) for superior oil control.