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Findings On Damaged Rb25Det

MJTru

By MJTru,
in Engines & Forced Induction

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MJTru Mentor

MJTru

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Posted

Hi Mate

I would like to share my findings, after i pulled my motor apart last month.

First off i should tell you the specs of the motor.

1. it has a built the block, has arp main studs, N1 oil and water pump, Eagle rods with wisco pistons, Bore 1mm over (87mm bore) ,6boost top mount manifold (t3) ,44 tial waste gate, AMS GT950R turbo, power fc, Custom intake with top mount fuel rail, 100mm tb, FMIC, external fuel pump, External fuel regulator, 800cc Sard injectors, Stock rebuilt head, MLS head gasket, ARP head studs.

After opening up the motor the first thing i noticed was damaged pistons, it looks to be like detanation, But this could be because i used a 86mm MLS head gasket on a bored block. Stock bore size is 86mm and i bored it to 87mm,but used a 86mm bore gasket ,opp's second misstake. Next was the crank collar was the short one, but it was still in good shape, next i had no oil restrictors in the block. Next i never installed a head oil return, and other that running 25psi on pump gas. Thats all i found that was wrong with the car. Well for most part the pistons were really bad and it caused the head to get damaged, cause peace piston ring broke off and hit the head.Plus the head looked like it had small hole in the parts that were in the combustion chamber. so again i think that was detanation.

The biggest thing i feel that cause or even aided the damage was the gasket. A 1mm peace of gasket like a round ring (looks like a piston ring 1mm round) fell in the combustion chamber. I feel this would have aided the detanation process. These small amounts of gasket can cause hot spots causeing preignition or detination. ???????

Well on my new motor (build 2 of them) Has all these things rectified.

If you would like to see the new setup check the link out mate.

its not much, but i do my own work. This is one of the 2 motors that i'm building.

cheers

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