RB25DET forged internals...

Thread in 'Technical Questions' started by Simon Skyline, Jun 20, 2014.

  1. Simon Skyline

    Simon Skyline Member

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    1) Any recommendations on the best brand for forged internals? :thumbs:

    2) Are there any special requirements for high boost? :smokin:

    3) How do I tell how much (or where do I find out) the max lbs / bhp of the pistons & rods, etc? :confused:

    4) Is it really worth increasing the capacity or just knife-edge, nitride & balance the crank? :cool:
     
  2. Stavros

    Stavros Active Member

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    1- They're all good. I ran Supertech pistons on my RB20, but all good. Unless you going spastic power they will all cope.

    2- Depends what you mean by high boost. But the correct compression ratio, decent HG and bolts, correct ring gap, removal of potential hot spots, and even mods to the block etc are all things that is used for REALLY high boost.

    3- Any aftermarket pistons/rods will easily be capable of 250bhp+ per litre if the engine is done right.

    4- 2.5 is fine, there much bigger things to worry about.
     
  3. Simon Skyline

    Simon Skyline Member

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    Thanks for the info mate... :thumbs:

    Not thinking MEGA boost but would like 2+ bar. :cool:

    When you say "bigger things to worry about" are you referring to fuelling or the usual oil control, oil pump & crank collar, etc? Is there anything else I should be aware of? :confused:
     
  4. Stavros

    Stavros Active Member

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    2bar and 8.5:1 should be safe on pump fuel if stuff is done right. Pushing it beyond that though on pump really.
    And considering most in the Jap car scene in the UK don't even run 1.5, 2bar is mega boost to most.
    I like big boost though, so I agree with your wants lol.

    I meant yeah, that usual stuff. But mostly, the money you'd spend increasing the capacity, spend instead using GOOD parts. Reliability and performance is not usually how many parts are modded, but how good the modded parts are.
    A proper twin scroll setup, an exhaust at least 3.5in from turbo back, an equal flow inlet plenum, proper oil setup (inc head oil drain), decent engine management mapped by someone who's actually good, etc etc etc.
    A well done engine pisses on a highly modified engine every time.

    And with the right turbo/cam/manifolds/etc etc setup, with 2bar+ boost, you will piss on 99% of cars with much bigger capacity and probably have far far more torque too.
     

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