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For those of you with forged internals, how reliable has your engine been? I ask because i need a rebuild but i am weary of putting forged pistons and rods in it. I have seen 4 built engines eat themselves in the past week (they were subaru engines though). The car is a weekend/nice day car with an occasional trip to the strip.

Thanks,

Brandon

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Got my engine rebuilt completed in November 2004 (rb25det), 33000kms after it still runs healthy no problems at all this is running 1.0bar of boost for circuit/street 1.30bar of boost for drags. Get below 20 knock on my pfc hand controller with the occasionally 25knock.

CP Forged Pistons

THICK metal head gasket (lower compression, i regret doing this)

Shot-peened and leenished, crack tested rb25 conrods

For those of you with forged internals, how reliable has your engine been? I ask because i need a rebuild but i am weary of putting forged pistons and rods in it. I have seen 4 built engines eat themselves in the past week (they were subaru engines though). The car is a weekend/nice day car with an occasional trip to the strip.

Thanks,

Brandon

Hey

R32 GTR rebuilt 2 years ago (20,000klm)

Wysco forged pistons

N1 Bearings

shot peen / balanced blah blah blah

Tomei head gasket - std thickness (a good thing)

running 1.2 bar all day every day (with N1 turbos)

Only problem I have is my knock readings can get up to 60 - but it's NOT pinging - this may be the wyscos, or high clearances - not sure which

light tune GTSt running around 200rwkw most days... rebuilt about 20,000km ago and have done about 4 motorkhanas and 3 track days (60+laps) with no problems... running Arias forged pistons and prepped/tested stock rods...

the knock sensors go crazy on mine but I have been told the Apexi stuff is really sensitive and due to the rather large piston to bore clearances (as spec by Arias...you could probably go closer but meh)...

on cold mornings there is audible piston slap and it generally idles a bit rougher than stock but I have a/m cams so that doesn't help

it all depends on what you want in the future... if you have no plans for major power upgrades I would just run standard pistons, they are generally lighter and quieter than forgies

I have done 8,000 kms on my GTR engine since it was built in Sept 05.

I use CP pistons and the engine is absolutely perfect - The only problem I have had since the build is a faulty CAS which I replaced with a brand new item.

Thanks for the replies guys, makes me feel better about putting some quality components in there. I noticed that you all are running CP, wiseco, or arias pistons. Anyone had any experience with JE pistons for the 26? I ask only because i can get a set of JE's with rings and Eagle H beam rods for $1040 U.S.

they dont all do it...my acls dont do it...i ran tighter then spec clearances both piston to bore and ring end gap and i dont get any slap. You get slap if you do it to the manufacturers spec...but it does depend on the application to which your running the motor as to what clearances you run.

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