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254 Or 265 Cams. :s

Cubes

By Cubes,
in Engines & Forced Induction

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Cubes Grand Master

Cubes

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Hey ppls,

Thought I'd throw this out to some of you that have had a bit of experience playing with cams.

Deciding on cams for the car; hope to have them in within a couple of weeks.

1. 254duration 8.5mm lift of which I've seen pick up 26rwkw on 1psi less boost up with power up around 250rwkw and it lost no bottom end, holds power after peak much better and interestingly an improvement in fuel economy.

2. 265duration 8.9mm lift cams.

Its an RB30DET, GT30r .82. The heads had a little work done to it, usual port polish/multi angle valve jobs, valve deshroud and is currently making close to 270rwkw on 1bar. Std inlet manifold, std exhaust manifold of which I wish to retain.

The car is daily driven as I wish to enjoy it daily. Currently returns 450km's to a tank of juice and scrapes 400km's if I give it a bit of stick.

The bloke tuning the car has said 265duration FTW as its a 3ltr and it will soak it up fine. I've seen the 254's return good gains so Im in two minds if I should or not as I wish to retain the std exh manifold and later down the track drop a WMI kit on it to see what I can squeeze out of it for a stock looking motor.

So who's had a play with similiar cam specs?

What were the gains/losses fuel economy idle quality etc? I wouldn't mind a bit of that horn RB lope. :P

Any of you have rough comparison dyno runs before/after the cams?

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STATUS Grand Master

STATUS

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increased capacity and static comp tend to tame cams, but if youve decreased the comp and increased the capacity you may well be back where you started. what comp you using? what boost do you run? Honestley a split setup works very well 256/264 for most mild setups and most of the new profiles of late seem to be this split type.

Cubes Grand Master

Cubes

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Cheers.

Static comp is up near 9:1; currently running 1bar and making 268rwkw. As I said above its had a little head work so compared to others on the same dyno with the same/similiar turbo it seems to be making 10-20rwkw more. Possibly the slightly higher comp is the helper.

Hrmm so 256/264. Might definitely have to consider that as the rb25 heads to tend to suffer a little on the exhaust side of things.

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