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I replaced my stock RB25DET cams to a set of 260 degree/10.25 lift Tomei Procams and Tomei Cam pulleys.

My car got worst and even with dyno and road tuning im very disappointed with the upcome of the cams.

A few tuners were scratching heads on this particular set of cams. The power is okay from first few ks RPM.

It flattens out after 4200rpm @ 270whp and kept a straight power curve line after that.

One of the tuner said, my VTC is giving the problem and i got the VTC replaced. Later on, they were saying my

spark plugs and i got it replaced too. Till now no one is able to to figure out why and i replaced back my old cams.

After figuring out why... Im giving another try on the cams. I special order the Tomei Valve Springs (10.25mm)

and a set of Tomei Solid Lifters. I'll see whats the upcome after those parts are being installed. Kinda regretted

getting the cams but im not giving up.

Just wondering has anyone tried Procams or is it just mine that is giving problems? Need some input here.

Anyway im running a HKS GT2540, PFC, Walbro 255, Sard 550cc, Nismo reg and internals are dead stock!

Thanks!

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yeah, we have had a few rb25 with "soft" springs float quite badly, from memory those cams are not supposed to be used with STD springs and hyd lash adjusters either... im sure they are solid only :D i would be looking at the profiles to see if they are damaged due to bind or excessive float. Who fitted them????

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man those cams are too aggressive had them in mine and took them straight out again... on the advice of john for jhh.... He told to stay far far away from them.... you won't get much power gains from them better off with poncams especially if no other work has been done to the head.

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man those cams are too aggressive had them in mine and took them straight out again... on the advice of john for jhh.... He told to stay far far away from them.... you won't get much power gains from them better off with poncams especially if no other work has been done to the head.

HAHAH SOUNDS LIKE WE ALL AGREE!

mate those cams do not suit your application lets put it to you that way unless your running a bigger turbo and soild lifter arrangement like uras said which is rite and have done a lot of work on the head u have wasted your money even if u put soild lifters and harder springs i dont see u getting much out of them with that turbo ! u should of went poncams mate!

i think u ordered the wrong ones...try poncams 260--- 9.15lift and then compare your midrange to topend to what your using now...big difference

cheers

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With a 2540 (not the best turbo in the world to begin with) - you probably can get away without even spending money on cams!

I ran a stock head for oever 300rwkw and had as good response as everyone else around here with cams :P

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I know the RB is very sensitive to cam timing compared to say a SR20. My rb26 at 12 psi made 180 kw with a crappy power curve, I dialed in the cams with a dial indicator and then adjusted slightly on the dyno and with only 16 psi the car went 290 rwkw.

???? were they in 180degrees out :/

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not quite but probably in the best position if you want to make the least power possible!! ill show you a graph.

post-29334-1193368392_thumb.jpg

let me guess no-name cam gears? i have had a few ground way off!!! like 10-20 degrees!!!!!

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nah tomei cam gears with tomei cams, i was thinking maby the block has been decked or different size gasket moving the timing around a bit?

at the first dyno to last the cams were pretty much opposite to where they needed to be, so who ever built motor didnt have much idea, or didnt dial them in.

Edited by GTR1993
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  • 6 years later...

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