Rb30, Realistic Na Power Figures

[Cubes]

Is the variable valve timing something I can use? BTW this is the one and only engine I intend to build for a 240z, so if it takes years I don't mind. With that in mind I'm intending to really go town, and I'm an electronics fan, so was thinking MoTec make the best ECUs? Probably get one of those, if I could get one with a switchable map that'd be great, that way I could map it for 99RON fuel and for 109RON fuel, I guess?

Are the RB cranks interchangeable? Does anyone know for a book that lists the component specs please? I have an L series tuning book that tells me all the crank dimensions, strokes, different piston dimensions and chamber ccs so I can figure out the right combination of parts. I need something for the RB.

The only way to make high power with a NA engine is high RPM with high compression, get the air in so you can make it.

Yes it is revs that kill a motor, light weight pistons and rods do wonders.

Use the link in my sig to dload the rb30 pdf.

[Russ_T]

Yes it is revs that kill a motor, light weight pistons and rods do wonders.

Use the link in my sig to dload the rb30 pdf.

Thank you! I just skimmed the pdf and am now printing it for my perusal, brilliant

http://www.automotiveforums.com/vbulletin/...d.php?p=4141983

That's another forum I've been chatting about this on. I wonder how you figure out your rev limit for an engine, or do use some informed guess work and hope for the best? I couldn't afford a destruction orientated development plan, and guess for the sake of not having to rebuild the engine regularly should err on the side of caution. If I could see 9500 rpm I'd be a happy chappy, apparently that's doable. 10k sounds better though, but probably both unrealistic, unless I can get some motorbike engine components into the equation.

Anyway will read the pdf, much appreciated.

[Cubes]

It really is only an estimate as to where others have broken oil pumps etc..

My self... I won't be taking mine past 6500-7000rpm but don't need to as I run turbo.

Bu5ter has the good bits, an ati balancer & full oil pump drive gear and takes his to 8500rpm.

I think realistically 8500rpm is pushing an RB to the very limit. Its proven even the ol' rb26 taking it regulary past 7000rpm drastically shortens its life (i.e bathurst)

[Nosmo]

Will an RB25/RB26 balancer fit the RB30 crank?

Does it make any difference to the harmonics problems over the standard 30 balancer?

[Cubes]

Will an RB25/RB26 balancer fit the RB30 crank?

Does it make any difference to the harmonics problems over the standard 30 balancer?

The rb's are all the same, the only difference is the extra deck height, everything is the same as the rb20/25/26 block.

So yes.. the balancers fit the standard rb30 crank.

Which is why I stated earlier, its been known for vlt's running around to break oil pump drive gears over 6500rpm, skylines, it appears to be some where over 7500rpm, when you look at any serious high rpm rb26 they too run aftermarket balancers so there is definitely something in it.

[BADR33]

im using rb25de oil pump. it was even worse when i was running 10w60 oil. now im running 10w30 so its a little better. its not that helpfull that i do rev the car out often.. it just revs so damn quick that you dont realise..

im using a 25 harmonic ballancer. i had all of my interanls ballanced from the clutch, flywheel, crank, rods and harmonic balancer. its a very smooth reving engine. once i get my exhaust fixed i will try either get a video or a sound recording of it. i have been trying to for 6months. but havnt had the time. or been that happy with the sound of the exhuast...

if you aim of reving over 7000rpm you might have to look at injectors and you will need an aftermarket ecu. i still need to get one for mine as power starts dying away just before 7ish. so you will also need some high lift and duration cams to still be making power up there. you would also probly be wanting to look at hex throttles to help with the breathing.

[Russ_T]

I'm going for aftermarket throttle bodies, injectors, entirely new valvetrain, ecu etc. I don't care if I have to replace everything, so long as the engine is a Nissan straight 6.

I know the Mines skyline was good to 8500rpm plus, and I'll need the revs to make the power NA.

I really need lightweight and strong rods and crank, with everything perfectly balanced and forged pistons.

Edited June 29, 2006 by Russ_T

[BADR33]

oh true. good luck man. ill be keen to see the results once its all done.

good on ya for building a high power NA. have you considerd the RB26 head much though? would save you a fair amount of $$ over time. and its easyer to make fit the block the a VVT head.

but yeah you will have a damn sexy sounding RB once its all done

[Sydneykid]

One day I will put one of these into a 240/260Z

RB30 block and crank

3.1 litres

13.5 to 1 compression ratio

Polished combustion chambers

272 duration 10.8 mm lift cams

Titanium retainers

Tome valve springs, 55 lbs at the seat

2 mm oversize inlet valves

1 mm oversize exhaust valves

Ported RB26 cylinder head

Ported RB26 inlet, multiple throttle bodies and plenum

Tuned, coned collector extractors

4” titanium exhaust

JE forged pistons

Carrillo rods and rod bolts

ARP main bearing studs

ARP head studs

ACL race series bearings

N1 oil pump, with wide flange drive crank collar

RB26 water pump

Elf LM fuel

Motec ECU

Motec CDI

Mercury outboard coils

WoooHooo……400 bhp here we come….and wouldn’t it sound good

cheers

[Russ_T]

BADR33: Thank you, I'll be sure to post my progress here (one day, buying a Z32 a the moment and finishing my other 240)

Sydney Kid: I love you, that is exactly what I need Sounds very much like what I imagined I'd need as well.

RB30 block and crank

3.1 litres

13.5 to 1 compression ratio

Is that 3.1 overbored? How did you get that compression ratio? I imagined the RB26 head had one of the bigger chambers (low compression), are you thinking of welding up and reshaping the head chamber, or is that a tall piston (extra weight?) or longer rods (better idea, good stroke/rod ratio for high revs), or a domed piston?? What crank?

Thanks all.

[culater]

MMMM VK56DE thats something i see in my fantasies....

Neways Naturally aspirated the only way to make power is REVS and lots of them, i was talking to Sydneykid quite some time ago about this and he said that the problem with high revving RB30's is they seem to get some wierd harmonics through which will eventually cause excesive wear on just about everything.... cant remember if he mentioned neways to eliminate this best u pm him i think, he's super friendly and like a nissan dictionary.

all six cylinder engines produce harmonics at revs.. they {and multiplr configs of 6 cyl..i.e. v12's} need a quality harmonic balancer to quench this.. 4 cyls and 8cyls dont even require a harmonic balancer if balanced correctly.. something to do with the 90degree firing cycle.

[Russ_T]

That's interesting.

One of these puppies then

http://www.atiperformanceproducts.com/prod...s/damnissan.htm

[Gav]

That's interesting.

One of these puppies then

http://www.atiperformanceproducts.com/prod...s/damnissan.htm

I'm running one of these on my RB28 - nice bit of kit but the 25% overdrive keeps shredding AC belts when I forget to turn off the AC switch (shouldn't be a problem for you 'tho).

[T04GTR]

theres still nothing like a hairy chested 3.1 L6 with tripple webbers and a cam so big it wont idle below 1500