Car - R33 gtst RB25DET 95,000km
Problem - noise in no.1 cylinder when hot at idle, goes away above idle or under load
Cause - bent No1 conrod causing the piston skirt to hit on the oil squirter that hangs into the bore to lube/cool the underside of the piston.
Tune - std engine internals with hi-flow ball bearinged std housing turbo running 12 psi, front mount cooler, full turbo back 3" to 4" exhaust, Wolf 3d computer.
This happened while the car was on the dyno getting the wolf rutuned after the turbo was installed.
Oil was castrol fmx gt3 (or something like that) changed every 5000km with a filter
All the rest of the engine was spot on eg, bearings and pistons
It is still unclear as to what actually caused the problem
Now - due to this little problem the engine now sports rb26 crank and rods with arp rod bolts, oversized venolia forged pistons with genuine nissan N1 rings and bearings. The only mechaning needed for this combo to fit in was a rebore for the oversized pistons. everything else bolted up. You have to love nissan for their thinking with the rb series as so much is interchangeable