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Hi Zdenko, put a set of Tomei's 256's in an R34 GTST and made 240 rwkw with a hi flowed R34 GTST turbo. That was 12 rwkw more maximum horsepower than the standard cams, but 20 rwkw more in the mid range. Result 0.4 sec 1/4 improvement.

This was the last mod we did, it already had HKS I/C, hi flow turbo, panel filter, alloy inlet tube, adj exhaust camshaft pulley, split dump pipe, hi flow cat, 3" exhaust and Power FC.

I would not recommend changing the cams until you have done the above. Better bang for your buck in these bits.

Hope that helps

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I have done some research, GTS-t VSPEC (SAU) and SydneyKid (SDU) both given useful information, however cams setup will varies from turbo / setup..even same turbo on two different cars..

Also different degree (mine is 264...tomei makes 256, 264, 272) duration will shift the boost early or after...but fatter the power band is what I chasing for..

PM me for the price..

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I agree with what your all saying, cams should be chosen with a turbo upgrade to maximise the power output, but midrange is just as important. If you go for really wild cams then you will loose power down low, so many are only good for drag racing. I think the 256's or 264's give you a nice usable street setup, and will certainly improve 1/4 mile times.

See'ya:burnout:

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Guest Peewee

dear zdenko i believe the cams that are in the R33 are already too ****en big but un fortuanatly the complete **** up that nissan call the rb25 head is so grossely inefficiant that chasing decent midrange is pretty much out of the question so you may as well try and get it all up top than try to get a bit back in the middle where the cams will be efficient to 5000rpm and the head start being efficient at 4500rpm (for example) you may aswell do the best with what you got and aim for it up top!!

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Peewee, I would have to disagree with you on the RB25 head and cams, yes it is quite easy to make a balls-up of choosing cams, so that you only get top-end power, but I have seen many RB25's with very good mid-range.

The head is far from inefficient, and there are examples of many making big (500+) hp.

See'ya:burnout:

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I'm with GTS-t VSPEC, the RB25 head is the same casting as the RB26 head. I have seen a mildly ported RB26 head make almost 1,000 bhp on the engine dyno and that's hardly an inefficient design. I have also seen an almost standard RB25 cylinder head on an RB30 bottom end do a 9.9 standing 1/4, that's hardly a inefficient design. I had a stock standard RB25 headed RB30 that made 550 ft lbs of torque at 5,200 rpm, that's hardly an inefficient design.

If you have previously had experiences with mismatched components, that is not really an indicator of inefficiencies or deficiencies in the design of the head. That's just poor selection criteria.

The end result is the sum of the parts, not the fault of one.

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I'd sugest either a set of 256's or 264's, both can be made to produce a smooth idle.

The 264's will provide more power, but don't go for too high a lift as you have hydraulic lifters.

Most of the manufacturers like HKS, Trust and Tomei produce excellent camshafts.

See'ya:burnout:

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