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Considering changing the cams in my new GTR engine:

Current Spec

RB26 Head

RB30 Bottom End (9.0:1 CR)

Forged Pistons

Forged Rods

Copper Head Gasket

O-Ringed Block

Twin 3240 Turbo setup

HKS 272 Step 1 Cams IN/EX

800cc Sard Injectors

Twin Bosch 044 Pumps (Feed)

I am to make ~450awkw on Optimax Extreme without pushing the engine past 7500rpm.

The reason I ask is i was told that shorted duration but higher lift cams will make better power than the current cams.

Ive seen that Apexi make a set of INLET-260/11.2 EXHAUST-260/11.2 and im thinking if these would be a better option?

Any advice would be appreciated

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twin GT3240's for 450awkw? sounds like a bit of over kill if you ask me why not go something more sensible for that power.. t04z maybe? there capable of making 460rwkw.. not sure how much power you'd loose thru awd system.. of maybe even t51r kai?.. you've got the engine size to take it

well to use those 2 turbos to there maximum.. i reckon you'd need a rev limit of lot more than 7500rpm.. even tho it is a 3litre.. but it'd probaly be better to go with something along the lines of 270's with 10.8mm lift.. send sydney kit a message.. just remember.. the amount of work that has to go with such big lift cams in these motors

while the head is off I would be doing some extensive porting along side the upgraded valve springs you'll need. Consider larger valves as well. If you are local to Brisbane I only recommend John White Race Engines for porting on the RB's. He is located in Holden ST Woolloongabba.

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