Rb22 400hp+

[sly32]

Hey,

I have a RB20 sitting at home, so i have decided to turn it into a RB22 not 24 because i will need to change the crank and stuff for a rb24 so ive heard, i will have custom exhaust and intake plenum with a 35/40 strapped on to in and alot of other stuff, but i need to know about the cam shafts, how much lift and what degree should i get? do i hav eboth exhaust and intake the same degree? also i would like this to make over 400HP safely and still have good response as in hit hight boost by 4500 latest by 5000, any1 who can help would b sweet,

cheers JV

[Simon-S14]

cant help on cam choice, but are you planning on getting some head word done? If not i would seriously consider a decent port and polish, along with matching both the intake and exhaust manifolds to the head. RB20 heads really need help in this area

[Roy]

I think it woupd pay to sit down and speak to an engiine builderonce you have purxhased your turbo. 400hp+??? HOw + is the + and is that at the engine or the wheels?

I would think a 3540 is too big for 420hp, be it at the wheels (GT30R would be better) or at the engine (2835/TD06-20G etc) But once you have your turbo in hand sit down with youir builder and discuss compression ratio, match porting and cams etc. Gut feel, dont forget the RB20 is only a little 2L so dont go too crazy with duration, the RB20 has almost as much duration as an RB26 std so they are not wanting for cam duration fromn the factory. Lift, i suppose sneek a little bit more in there....if i ever try another set of cams its going to be something around the 254/8.5mm lift.

cant help on cam choice, but are you planning on getting some head word done? If not i would seriously consider a decent port and polish, along with matching both the intake and exhaust manifolds to the head. RB20 heads really need help in this area

Ppl talk of the poor flow of the RB20, they are only small pots so if the valves and ports/runners were the same size as the larhger RB engines you would end up with low velocity and poor turbo response. Compare the valve size per cylinder cc to somehting like an SR20 and the RB20 has more valve area and i suspect better flow. So unless the builder has years of experience with the RB20 and porting, then i would stick with just a simple clean up and match porting. They raced Rb20s in ther R31 GTSR and the race engines were lacking exotic mods/builds to punch out good power and reliability. 420-450hp is what they raced with, and that was made with only 2L and old school turbo. The extra 200cc and keeping some compression in the motor will make it a pretty good thing.

My fear with the RB20 is when you start complicating things with aftermarket inlet manifolds, cams, headwork etc etc...well all that money nets you maybe a few more hp etc, and the cost of a bigger engine gets blurred as an RB25 or RB30 building blocks are so cheap...with know good results.

But, im about to start ripping some engines apart to see if i can get a budget 20 together as i want to have a go at building an engine

[sly32]

hey, yeah i plan on doing everything like port polish, acid dip, getting a higher flow oil pump from greenline.jp costing me a shitload, money isnt a issue really, i mean sure we have limits but every1 is saying do a rb25, the problem with that is i would like something not every1 is doing and make it faster then theres , its not to late on the turbo i can always change it to a 30/40 or something a bit smaller, cams i have been told to keep the same degree cams on both intake and exhaust, but i will be talking to a builder to find out what he thinks, i would prefer not to use over 18psi to keep this engine in real good nick,

cheers for your help JV