Rebuilding the RB25.

[DETurbine]

Well my rings are shot, so I am going to tear it apart over the winter and put some forged pistons in, metal head gasket, ARP head studs, and maybe cryo treat or shot peen the rods.

I am either going with JE pistons ($570 w/rings) or Wiseco ($660 w/rings).Just trying to figure out what the compression is on them, since it doesn't specify it in the sites I am looking at. Does anyone know?

Also which are better between the JE's and Wiseco?
Modified by DETurbine at 4:28 PM 9/9/2004

[Joe]

compression ratio is relative to many other thingscylinder volume, head gasket thickness, CC volume (wich is relative to the piston dish/dome), deck clearance. you need to find those before you get a TRUE CR number.

and what are the specs on both the JE and weisco's?

[DETurbine]

Headgasket is going to be a 1.5mm, and am hoping the head is in good shape so the hone won't be that agressive. Also I called JE and Wiseco and the JE's are the RB26 and are 8.5:1 and the Wiseco's are 8.1-8.4:1. Think I am going to go with the Wiseco.

[DSMs_Suck]

WHy does the heads condition have anything to do with the hone?

[JonPowell]

Stock RB25DET compression is 9.0:1Stock RB26DETT compression is 8.5:1

[goofynick6]

If you're getting forged units, I'd stick with the higher compression...it'll be more fun to drive, and take less boost to achieve a power level. Less boost= less heat and more compression = less lag..etc. If you've got the right parts, the higher compression is awesome.

Nick

[DETurbine]

Would love to keep the 9.0:1 compression, but for the money I am looking at spending on the pistons the only option I have are those two. The Wiseco's will be good. Lower compression, which means more boost with less worry. anyone know of a place that sells RB25 ARP head studs?

[Joe]

If you're getting forged units, I'd stick with the higher compression...it'll be more fun to drive, and take less boost to achieve a power level. Less boost= less heat and more compression = less lag..etc. If you've got the right parts, the higher compression is awesome.

Nick

higher compression also = more risk of detonation. i would run 9 or 8.5:1 on a RB engine with moderate boost.