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Also I remember someone saying the RB20 has to rev more than a 4 cyl???

Maybe more agressive cams might suit RB20???

ok here we go this is my knowledge

the bigger duration you have in a cam the higher you move the power band in the revs, using a small turbo (stock rb25) you would be going backwards by doing that as it will make its most useable power down low in the rev range befor dropping off. by reving the titts off it (mainly cos it can) is a tottal waste of time as your making the power drop off even higher in the rev range.

but if you run a larger turbo lets say a gt30r as i am, it wont make incredible down low power but it will peak half way through the revs and keep climbing, so you use your cams to take full advantage of that range and make more power or bring it on slightly earlier with adjusting where the cam takes in its full efect.

so to answer mikes question no you dont need stiffer valve springs for the cams, but in your application of turbo its almost a waste installing them as your gonna make the motor work in a way the turbo cant support

Edited by AD4M
Now looking at the difference in displacement etc then you can start to appreciate that the cams in the RB20 are not exactly small to start with. They have same/similar duration as bigger RBs and only a little less lift then the RB26.

So you then consider that the RB20 has smaller ports, runners and valves. But it has to because it only displaces 2L, if it had runners and valves the same size as an RB25 then its gas velocity would suck and would not be able to spool the std turbo let alone an aftermarket one.

I think along the same lines UNTIL you start making similar power levels of the rb25/26 etc.

An rb20 making its peak power at 6500rpm compared to an rb25 making peak power at 6500rpm is moving the same amount of air through the motor. The problem is the rb20 has smaller valves so it needs the larger cams/lift to allow the same amount of air to move before the restriction increases. of which results in higher boost levels.

But you are right comparing the rb20 to the sr20 I really think the rb20 has a huge advantage. 6pots with 30mm inlet valves vs 4pots with 34-35mm inlet valves.

What was interesting is that 11sec RB20DET with stock cams, that had a custom

intake plenum, bigger turbo on stock exhaust manifold.

When you look at what he went through with his build, it's just simple, fast -

http://www.cardomain.com/ride/630659/3

I think he posted his 1/4 time, etc on SAU forum somewhere. The above link has the time slip and I think videoclip of run, etc.

Here's videoclip link -

http://www.cardomain.com/ride/630659/7

Edited by SKYPER
  • 3 months later...

Bump to an old thread:

I am looking at a set of these from HKS

IN 264 9.0

P/N: 2202-RN174

EX 256 8.8

P/N: 2202-RN171

OR

EX 264 9.0

P/N: 2202-RN175

The pair of 264's with my TD06-L2 I think would be a winner.

I just want to fatten the power curve I have to get boost on a tiny bit earlier and fatten up the power curve from around 4,200 to 5K, after the L2 takes care of things, however the cams I suspect will also half bring up the power from the time they "kick in" so to speak to redline.

However I am unsure if I should do cam gears at the same time?

OR

Is it worth doing gears then cams later on?

I would rather do it all in one hit, but for sake of R&D maybe just gears? (I have a set sitting at my other work calling my name) :D

Thoughts...

Cheers

-Jez

Will be interesting as i have a set of the 264 HKS cams for my engine as well. Not sure if i should bother as they are very similar to the Apexi cams i had which i removed. Hoping that the ramp rates etc work a little better in the RB20 but if i were you no matter what way you go, get cam gears and have a play with the std cams, you may bag what you are looking for just with cam tweaking

Hello

I am going to put HKS 272 with 8.5 lift camshafts into my R32 GTS-T with a RB25 turbo, upgraded fuel pump and injectors(They are RB20 camshafts). I read the HKS website and it said that their camshafts are direct replacements and are made to fit stock valve train components. Does this mean that I can put them in without tuning? Also since they are stock lift, do I have to change the lifters to solid lifters?

Please help

HKS don't make 272 camshafts for the RB20 and haven't for as long as I've been selling them.

So are you attempting to use RB26 camshafts instead? If yes then don't forget they are made for solid lifters and have a different profile to suit.

Stick to the correct camshaft for the application will be easier.

Cheers

Marty

definatly do gears at the same time!

when i installed my hks 264s and tuned the car, we adjusted the inlet cam 3 degres advance and it moved the power curve foward a fair bit. if we had of retarded the exh cam we think it would have made even more improvements

  • 1 month later...

ahhh dont you just love reading old threads...

no in all this no cams, yes cams business.... has anybody considered wank factor into anything?? the first mods anybody should do is bee r rev limiter and some cams... just for the sheer fun and shits and giggles of having a lumpy idle and dumping flames

with everyone talking about power curves, and flow testing, and comparing the rb20 to an rb26... noone has considered the enjoyment and the sound of hearing a lumpy arse rb engine.. barely idling away and shaking the whole car.. maybe the cams are a waste of money power wise.. but who really cares.. will it drop in power?? i know people that have spent $700 on the hks metal flow air filter when it first came out years ago... it made bugger all difference over the super power flow it replaced, but the sucking sound was more audible, hence making it more fun, hence not such a waste of money

at the end of the day... cars should not be measured by a dyno sheet... a 400m time... a lap time... or (if you drive a lancer) an spl reading... cars should be measured by the smile on the owners face.. thats what counts.

cams are awesome and there should be more of em.

cheers

Linton

I got some Tomie 270 cams for my RB20. I'm running a big T3/T4E (SC61) so I'm not going to have much bottom end but who cares it's a 2.0 for crying out loud. I wish I knew how the car ran with them lol still waiting on my 02 housing to built so I can bolt everything up.

newsetup1.jpg

  • 7 months later...

Hey, i got a 32 with a rb20, its got GTR injectors, fuelrail, cooler, recirulating valve on it. its got a HKS 33/45 turbo with a 3inch system and it runs 14psi everyday (can run 18 safely) any advice on which cam would be best suited to the car i was looking at the HKS 264s but im bit unsure any advice?

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