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Hey guys,

I was wondering if people could help me out and explain what the cam specifics (degrees/lift) mean and how they affect the car?

Currently running a gt35r with a rb26/30 head. Most people advise 260s with 9.15lift as they are the maximum you can get without modifying the head. ive had a look around and found some of the following pon cams

Duration: IN 260, EX 260 Lift: IN,EX 9.15mm

Duration IN 260, EX 252, Lift: IN,EX 9.15mm

Can someone explain to me what the degrees affects by lowering or increasing it? and what happens when you have a higher or lower inlet or exhaust lift? What are the consequences when doing either or?

Thanks guys

Edited by Jap_Muscle

ks for that ash. was a good read. I guess my questions now are.

how does having a bigger IN duration compared to a bigger EX duration affect things?

how does one determine what cams to choose based on an ideal rev range? eg if I want the action to be around 4-6000rpm, what do I look at?

i prefer to use larger exhaust cams on sr's @ around 300rwkw 264 inl 272 exh.

on the rb's its all about the capacity, 3l will take a big cam without any loss whereas a 20 withe the same cam will be a dog.

On your 26/30 i would go 260 in and exhaust.

look up the t67 on stagea thread a few posts down, i just did a back to back on a rb25 with cams and t67 dyno results are there.

it seems everyone does agree with you trent. 260s are the way to go i guess.

as i mentioned before my redline is currently at 7000. what can i do to increase it safely? do i need a new crank? would it be worth it even as i hear shifting to the next gear would give me more power anyway? it seems the rb30s run a bit out of puff in the high revrange.

RIPS rb30s consistantly rev to 9500rpm all day though =[

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