Camshaft selection (RB25DE head/RB30 bottom)

[InterC00l]

Looking for cams for this engine setup. Preferably HKS's. Here in the US, it's impossible to find ANYTHING for the RB series. Are all RB series cams the same (critical dimensions, not lift/duration)? What I'm asking is, are cams for a RB20 head compatible with a 25 head? What about cams for a 26 head? Also, does the VCT affect anything as far as compatibility? I hope I'm not confusing you all too much, I'm new to the RB series. Also, if you could suggest shops that I could get these parts through, or even just part numbers to cams that will work (pref. HKS). Thanks

-InterC00l

[Steve]

Hi, might be able to help with a couple of things,

HKS step one cams are compatible with NVCS, and will bolt straight up without any mods to the heads.

I am having fitted 256/8.8mm in and 264/9.0mm exh (both step one), which appears to be a good combo for the street and track, also will be fitting an adj exh cam gear to dial it in.

If you want to retain the NVCS, you cannot fit an adjustable cam gear to the inlet side.

HKS cams can be bought through www.greenline.jp at quite reasonable prices, but the us has HKS dealers, cant they order them in for you?

Sorry about part numbers, my cam boxes are in the workshop as my cams are being fitted and I am at home. I will try to remeber to get them next time I am down there.

RB26 cams are not compatible with NVCS also they are solid lifter, RB25 is hydraulic.

RB20 cams - I know nothing:).

[Sydneykid]

Hi Intercool, Steve covered most of it. RB20's are the same as RB25's except they don't have VVT. So you can use GTR cams in RB20's. Keep the lift under 9 mm and you won't have any trouble with using solid cams with the hydraulic lifters.

Our preferred camshafts for RB25DET are Tomei Poncams, they work very well with the VVT. There are accurately timed so we have found no advantage from using an adjustable camshaft pulley on the exhaust camshaft.

Hope that helps

[Bl4cK32]

Yeah, and the R32 RB25de doesn't have VVT.

[InterC00l]

What about a solid lifter conversion? I believe Tomei makes one. Also, is it just the R32 RB25DE head that does not have VCT, or do all naturally aspirated RB25 heads lack VCT. I would rather run without the VCT.

As far as getting these in the US, I have people that can, but finding documentation on such items is dificult.

-InterC00l

[Steve]

RB25DE from R32 does not have NVCS, from R33 it does.

If you want solid lifters and no NVCS, why not just use an RB26 head on your 3L bottom end. Probably easier and cheaper, plus you get the nice 6 throttle body plenum.

RB cams/NVCS specs are here: http://www.tomei-p.co.jp/_2003web-catalogu...haft-specs.html

[rb20-calais]

Sorry just to confirm if I buy cams from an RB26 they will work in an RB20? As I understood what Sydneykid said this is true but I just want to make sure.

Evan

[InterC00l]

Thanks for the info, helps a lot. Now, any idea how much an RB26 head is going to cost me?

-InterC00l