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hey guys,,, really was in some need of experienced SAU advice on my cam issue,, i am currently running stock cams on my rb20 with cam gears not really using much adjustment,, running 210kw atw highflowed 25 turbo , 550cc , z32 bosch 044 remapp comp , fmic , superspark coilpacks , full exhaust ,, this is great atm

But i am currently now ,, getting new piggy back ecu , changing actuator rear housign and centre not sure to specs but will be about 450hp rated and putting a more intense tune eg 17 - 19 pound of boost more lean,,, i need some cams i could very well go buy some poncams for 1000$ and then some valve springs for liek 300$ ish roughly ,, but was wonderign what rb26 cams and springs would be like??? anyone done this what are the pros / cons compared to stock cams will be run with adjustable cam gears....?? or does anyoen know if you can regrind stock cams??? will aparently be pushing a very laggy 270rwkw with stock cams some experienced imput would be greatly appreciated or even some 2nd hand cams if someone has any in SA!!!!

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I really think that the 20 head doesnt benifit from cams as much as a SR or RB25 etc does. mainly due to the smaller size of the runners and so on. If you ported a RB20 head and spent some time on it. then doing a cam upgrade would start to see some gains.

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yeah tru will be getting some before and after dyno readouts on cam and other bits and pieces and post it up on here for everyone else

Thing is, dyno results are not the be all and end all, so i hate to say it but you'll find it might be a big costly lessons for nothing.

Why go down the road someone else has travelled and turned around on?

Roy's car is circuit raced - that is where you truely tell if a modification is worth it or not.

Not on the dyno under nice controlled conditions :(

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...end result? went back to factory.

Yep, if you are using a 450hp turbo i would thin that its possible cams may help you out. I personally would not try anything bigger then 256/8.5mm Poncams.

I tried some 260/8.8mm cams and whilst it sounded so cool and tough, i lost power. Bascially killed the engine as it simply didnt have enough compression or cylinder filling and then when the cams would have finally come on at the higher revs all the gases were being choked by the little 8cm housing on my TD06-20G,

So in went the std cams, and got all the response and power back.

Dont forget that RB25s run more compression then the RB20 and they also hae VICS which is why they often get nice results with cams.

I am toying with the idea of again trying some cams in my new motor when/ if my std RB20 blows up. I will be just cleaning up the head (no porting i want to keep velocities high to get good cylinder filling) and bumping static compression up to 9.2:1 and then using 260/10.25mm cams which will effectivly lower dynamic compression of the motor. But to go with this i will also have a few cc more displacement courtesy of 4mm oversized pistons and a bigger turbo with less back pressure at high boost...and also a plenum that many clean up flow a little.

But for a std RB20, i would only try the 256/8.5mm cams with the std springs as i suspect they will be about as big as you want to go.

Just look at the std cams in the RB20, RB25 and RB26 and then consider the displacement and compression of the bigger engines and you will see that the RB20 runs decent sized cams std and unlike the SR20 which really needs some cams in the early to mid 200-250rwkw range...the RB20 seems happy with std camsa

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I've never considered the need for cams in my RB20, the standard engine is a great set up destined for boost from inception so the Nissan engineers spent quite a few hours getting it right :( go with their experience and leave em be

EDIT:

""Looking at your other posts, you want to move on from the RB20 anyway, so dont waste the cash.""

- i didnt read through em all.

Edited by abacusnow
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you dont need to change springs.

I have used hks 264 9mm cam's with good result's on my own motor, then my freind that purchased them off me had a back to back comparison and that saw around 500rpm quiker spool, and more power at less boost.

fit the adjustable cam gear's at the same time and you will see even better results.

If I were to do it all again, I would use camtech's

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thanks for all the insitefull info ,, i was looking at selling it but it is now off the market going on the path of wasting more money on it !!! i may have to check this camtech out ,, are they local australia or us or something???

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