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Running 270 Degree Cams On Rb25 Turbo

Bliksem

By Bliksem,
in Engines & Forced Induction

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Bliksem Veteran

Bliksem

Posted
Posted (edited)

I have an opportunity to pick up some aftermarket cams for RB25DET rated at 270 degree's duration and 8.9mm lift. Problem is i dont have an aftermarket turbo yet, but plan to get something along the lines of an AX53B70 P25 (375hp) in the future.

What would be the effects of using these on the stock turbo until i uprade?

Edited by MintR33
Warpspeed Experienced

Warpspeed

Posted
Posted

You absolutely MUST have a very large turbo and very free flowing exhaust for those big cams to work.

With stock turbo and exhaust, back pressure in the exhaust manifold is going to cause massive reversion with so much valve overlap.

It will be cranky and gutless down low, will feel reasonably good at very small throttle openings at higher Rpm, and will die in the bum completely when you floor it.

As Nismoid says, it will throw the air fuel ratios completely out. I don't think you are going to be terribly happy with it.

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