Rb20 Limits

[RB ONEVIA]

What are the limits of the internals? how much kw can they handle and whats the most psi you can squeeze into a standard engine? theres a R32 in hpi thats 302rwkw on standard internals. i searched and the best thread was from 5 years ago....

http://www.skylinesaustralia.com/forums/st...=RB20DET+Limits

[kat_00seven]

hi, in regards to the countless people out there who think the RB25DET can't handle good hp on stock internals i have a Street Commodore magazine in front of me now with a VL calais in it with a RB25DET conversion, on stock internals with some very nice bolt on mods pushing 454.3RWHP / 339RWKW @ 18psi.

If thats possible from some holden nuts with half an idea (i say that as the other half that didn't have an idea did it all in a holden HAHAHA) then surely a couple skyline enthusiest's can do the same.

Street Commodore #140 (june 2008) page 60.

[RB ONEVIA]

i just got a bigger turbo and im aiming for around 250rwkw on 18-22psi. i was going to get a metal head gasket but if i dont have to i wont. just dont want to be blowing it up just yet. aparrently RB20s are stronger than RB25s but smaller capasity so takes more to get more out of them.

[N1GTR]

Speak to Roy

[RB ONEVIA]

who is this Roy you speak of??

[bubba]

Or speak to AD4M, he was making nearly 400rwhp out of a stock RB20 with cams and a GT30 I think..

[R31Nismoid]

hi, in regards to the countless people out there who think the RB25DET can't handle good hp on stock internals i have a Street Commodore magazine in front of me now with a VL calais in it with a RB25DET conversion, on stock internals with some very nice bolt on mods pushing 454.3RWHP / 339RWKW @ 18psi.

If thats possible from some holden nuts with half an idea (i say that as the other half that didn't have an idea did it all in a holden HAHAHA) then surely a couple skyline enthusiest's can do the same.

Street Commodore #140 (june 2008) page 60.

Sorry but that doesnt really prove a thing. Shows the power can be made and thats it. You can make 500rwkw on a stock RB26, seen it myelf.

Doesnt mean the motor is in one piece these days (it didnt last long).

It comes back to the age old question what do people define as handle/be reliable etc etc?

1 year? 3 years? 5 years?

20,000? 40,000? 100,000?

Does it get driven with 340rwkw HARD every day? (on the street, very hard to believe thats remotely true)

Does it run 250rwkw daily with adjustable boost? (as an example)

What was the condition of the motor beforehand?

There are so many variables, questions and related that go well on from just those above.

I would say reliable would be deemed with the following - at LEAST 5 years, and at LEAST 60,000kms , and driven reasonably hard a couple of times a month with the odd track day, odd drag meet each year (2 max)

So in taking the above variables, NO - the RB25 cannot hold decent horsepower (340rwkw example) reliably in my book at all. Can it MAKE the power? Ye of course. Is it reliable? No.

Longest was what, 18-24months before it destroyed itself, and it wasnt driven daily (from memory).

So as you can see, one magazine article is hardly anything to get excited about when you actually sit down and really look into it rather than the glossy pictures.

On the other hand (with things we actually know) Roy on the forums has run 250-260rwkw for a number of years through his RB20 and it has a number of track days under its belt. The car is pretty well looked after, isnt driven daily, and runs like a dream on the circuit and has for roughly 3-4 years now.

So you could say safely the RB20 could hold 250-260rwkw for a number of years if tuned and looked after in the appropriate manner.

Has every RB20 run for that long? Possibly not.

So you've gotta take everything on its own merit.

[Ronin 09]

[TTT]

who is this Roy you speak of??

Roy is what the "R" in RB20 stands for.

click vid in my sig to see what ROYB20det is like with 250rwkw on 20psi.

that is a $600 wrecker motor with bolted on bits.

[Wheezy]

277rwkw here on a stocker since july......driven once or twice a week relativley hard....

Hope to get some track days in and see it last a few years

[AD4M]

my first tubo setup on an internaly standerd motor,stock cams,stock inlet plenum & throttle body and just an std rb25 exhaust mani with the trust TD06 20G with a big 16c rear housing made 405rwhp on 26psi and ran a few low 12 second passes. i drove that setup every week for a year and it was always running 20psi or more

[RB ONEVIA]

its my daily so will be driven most days but not at maximum psi would like to go to the strip and crack 11s. just dont want to be getting blocks every couple of weeks. would it be wise to throw in a head gasket?

[iz32]

i concur!

i've been running 20psi constantly for the last 2 years and still going.

its not daily driven but every weekend it sure gets a good run.

as long as the tune is good the RB20 is good for it.

[RB ONEVIA]

my first tubo setup on an internaly standerd motor,stock cams,stock inlet plenum & throttle body and just an std rb25 exhaust mani with the trust TD06 20G with a big 16c rear housing made 405rwhp on 26psi and ran a few low 12 second passes. i drove that setup every week for a year and it was always running 20psi or more

i thought i recognised your car... its the one i was looking at in the latest HPI...

[AD4M]

i thought i recognised your car... its the one i was looking at in the latest HPI...

issue 99? thats the one with a full feature on it but dont think its out yet?

[RB ONEVIA]

yeah 99 came in the mail yesterday, should be out sometime next week...

[AD4M]

ohh awesome

8 months since it got shot, ive been waiting patiently haha

[RB ONEVIA]

8 months???? i would have thought 5 at most. have you changed much since then??

[AD4M]

i was told 6 at the most! but oh wells cant control these things

the motor let go the week the shoot was done (it was blowing bulk smoke out the breathers) and ive since sold all the turbo kit,cams,ecu and a few other bits. besides that its just sat in the garage waiting for its new motor but thats some time away yet

what you see in that feature is basicly my recomendation for the perfect 20, the car that the gt3040r turbo kit,ecu and injectors went into is making 300rwhp on a lazy 16psi and is just as responsive as the rb25 turbo that came off it!

Edited October 3, 2008 by AD4M

[Italiazr1]

in regards to the top question my car before i had it rebuit was set to 20psi running everyday pump fuel it let go a month later because the head gasket blew.

a few other things contributed too but anyway dont run over 20psi unless you got race fuel

pump fuel sucks dude you will blow your 20 pretty quick if youve just bolted up everything to a stocker

im making 241rwkw now after my expensive rebuild the engine pumped out a 260kw run but we detuned just in case somethin let go

i reckon my car is capable of 280 - 300 kw if i stick some boost in it and tuned it to race fuel for a couple of passes

my other question to adam was that ive got a gt30 in mine now but its bloody laggy 5000rpm starts to com on hard

did cams make a big difference in your car?

im gonna change my turbo to the 3071r same power less lag? what you reckon?