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In what order would you recomend moding an RB25DET and what increase would each mod make?

I would like to get to about 350 - 400BH.

The engine is out of the car at present and being stripped as it needs a re-bore. I was thinking about lower comp forged pistons and possibly steel rods (pauter or another make) or would the standard rods cope with that power?

Any advice appreciated.

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Thanks Jim,

So the internals will cope with what I want from the engine over all. I will be using the car every day, I'm not in to drag starts all the time but love mid range and top end power. This is probably due to being impatient so whenever there's a gap I take it.

How do I get the engine to develop 350 - 400 HP?

What does the standard clutch bomb out at or will this take 450HP too?

Cheers

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350hp can be done on the standard turbo. Much higher than that and you'll probably need to get it highflowed or replaced with a bigger unit.

Other usual mods which should probably come before this are 3 to 3.5" exhaust, upgraded ECU (S-AFC or PowerFC for example), upgraded boost via bleed valve or electronic boost controller, bigger fuel pump, umm that'll probably do it actually. A frount mount intercooler will also probably help.

I've heard mixed reports about the standard clutch. Some say it needs upgrading at around 300hp, others say it holds over 400hp. Best off just see how you go, and replace it when it starts slipping. If the engine's already out and you're replacing it anyway, then definitely go for something beefier.

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Over 200rwkw and you will need to replace the factory clutch with a grippier one - 5 puck kevlar or twin plate.

I haven't seen too many Skylines pulling more than 200rwkw with standard turbo.

To get more than 300 rwkw i reckon you will need big turbo with ext. gate for sure.

Re Rods - I have heard it it a lucky dip - some std ones are good some are ordinary - Replacing rods with forged ones is expensive - maybe just check yours out and get strenghened Linishesd, SHot peened, cryo tempered - should be cheaper then new rods and OK for 350-400HP no probs.

Get a good ECU - a proven one - ie PFC

Most important though - is the tune . Make sure you take it to someone who knows what they are doing - Lots of people will say yeah, yeah - easy easy - But ensure your tuner is professional, no bullshit , experienced.

Remember - you get what you pay for - don't skimp on a cheap tune !

Hope that helps !

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