R33 Rb30 Conversion

[CEF11E]

Thanks Cubes, I will be limited to around 17psi with a slide hiflow due to the high shaft speed it will be spinning at to supply the 30det. I don't really want to run much higher boost for a street driven car anyway. mind you I would be pissed if it waa goes together and I am limited to 14psi. I want to be able to run the turbo at maximum efficiency. so it looks like I will have to do something.

I am hoping the hiflow will produce 250~260rwkw on the 30det as it would make 241rwkw on the 20det.

A turbo upgrade will be on the cards in 6 months but I don't really like running super high boost.

[Scooby]

much more accurate description than mine . Looking at the standard RB26 map, the AFR's would be 10:1 if using an RB30 bottom end and putting your foot down at 2400rpm.

Thanks Sydneykid and Nic, I've found a PFC to borrow and will be addressing the issue as soon as I can get it tuned. Luckily there hasn't been that much 'running in' yet. In the meantime you might be interested in this:

http://home.aanet.com.au/nistune/docs/NISt...Quick_Start.pdf

http://home.aanet.com.au/nistune/docs/NIStune_FAQ.pdf

Cheers

[122]

hey guys,

go easy on me im a newby here.

ok first post. Is doing the rb30/25-26 conversion the best RB combo. I can see how the extra capacity helps and that it might be an advantage for an rb25, but is it worth doing this to an rb26 engine. i would have thought that having a rb26 block & head would be better considering they came out on the gt-r, and if they wernt that special then wy didnt they make them a 3 litre block form the begining.

What i am trying to get at here is, would it be better having a RB26 complete block and head or a RB30/25/26 combo??

sorry for the question but its puzzled me for a while now to the point where i actually joined the forum and am asking this lol, also has anyone got any pics of there setups i wouldnt mind seeing some.

cheers.

[shanef]

hey guys,

go easy on me im a newby here.

ok first post. Is doing the rb30/25-26 conversion the best RB combo. I can see how the extra capacity helps and that it might be an advantage for an rb25, but is it worth doing this to an rb26 engine. i would have thought that having a rb26 block & head would be better considering they came out on the gt-r, and if they wernt that special then wy didnt they make them a 3 litre block form the begining.

What i am trying to get at here is, would it be better having a RB26 complete block and head or a RB30/25/26 combo??

sorry for the question but its puzzled me for a while now to the point where i actually joined the forum and am asking this lol, also has anyone got any pics of there setups i wouldnt mind seeing some.

cheers.

atleast read the pdf that has been created (its at the very beginning of the thread)

also this question has been asked & answered HEAPS of times before, so please do a search

[linedup33]

122 - i reckon a 3 litre gtr would b beta than 2.6 litre gtr

Edited August 2, 2007 by linedup33

[Al]

Thanks Cubes, I will be limited to around 17psi with a slide hiflow due to the high shaft speed it will be spinning at to supply the 30det. I don't really want to run much higher boost for a street driven car anyway. mind you I would be pissed if it waa goes together and I am limited to 14psi. I want to be able to run the turbo at maximum efficiency. so it looks like I will have to do something.

I am hoping the hiflow will produce 250~260rwkw on the 30det as it would make 241rwkw on the 20det.

A turbo upgrade will be on the cards in 6 months but I don't really like running super high boost.

With any hi-flow you'll be choking the engine at about 5500rpm and the power will drop rapidly; as the turbo can not flow enough gases. Just letting you know, in case you wanted to rev the engine to 7500rpm .

[122]

thanks linedup33, do the timing covers fit on the rb30/26 i ask becuase ive seen a couple of these combos but none have the timing cover on for some reason?

shanef - also i am still slowly getting through this thread and i cant find the pdf u are referring to but i am still looking, thanks.

[shanef]

thanks linedup33, do the timing covers fit on the rb30/26 i ask becuase ive seen a couple of these combos but none have the timing cover on for some reason?

shanef - also i am still slowly getting through this thread and i cant find the pdf u are referring to but i am still looking, thanks.

sigh

[122]

thanks shane

[WPN-O33]

Hey guys a quick Q my mate has just bought a N1 oil pump for his RB26/30engine build & is getting some bad feedback from his workshop saying a few of these hav let go. Just quickly he rang & asked if i knew anything. What do u guys think any recommendations? or is this a good option???

Anybody??????

[BAMR33]

Hey guys a quick Q my mate has just bought a N1 oil pump for his RB26/30engine build & is getting some bad feedback from his workshop saying a few of these hav let go. Just quickly he rang & asked if i knew anything. What do u guys think any recommendations? or is this a good option???

Anybody??????

Read the frickn thread, this covered just three pages ago.

Quote GT-RGeoff:

Not a fan because the N1 is a much more brittle material so doesn't have much residual toughness for things like bouncing off the limiter, but that does happen even if you don't want it to.

Also there is no real justification for much higher oil pressure/flow. All it will do is deposit more oil in the head which you then have to get back to the sump for pickup. Oil system function and efficiency is not based upon the amount of flow or delivery pressure, but the maintenance of the thin film of oil between moving metal components. Oil pressure does not provide lubrication; oil presence and viscosity does it. Some systems use the natural viscosity to pull the oil through without a pump.

It would be great to know that the flow is moving the oil through to prevent overheating and molecular breakdown, but pressure is always a measure of restriction when it comes down to the final analysis so a high flow pump giving greater pressure head is simply showing the restrictions present, and therefore the lack of ability of the high flow pump to really make any discernible impact.

[GTRgeoff]

Caleb, I assume you haven't driven a GTR then. They are a particularly lazy engine and take a little while to make power when off boost. I guess the lower compression compared to a GTSt is the difference, as well as having to crank up 2 turbos that make more than the GTSt singles.

A 30 will have more torque at the same CR and benefit from the modern head for flow and response. In my case I have 9:1 CR so it should be even more torquey. It made 160rwkw as an NA with the turbos hanging off it and as I noticed today putting new cam gears on, one tooth out advanced on the inlet so has been particularly sluggish. More to follow when I get it running again btw guys.

As for a R34 GTt head, our mate Spoolup has one so look him up, plus source your cam gears/rods/CP pistons from him.

Oh and Shane, while you look and remind me of Ash (la Nismioda) , we really really only need one of him.....

[CEF11E]

Thanks Sydneykid and Nic, I've found a PFC to borrow and will be addressing the issue as soon as I can get it tuned. Luckily there hasn't been that much 'running in' yet. In the meantime you might be interested in this:

http://home.aanet.com.au/nistune/docs/NISt...Quick_Start.pdf

http://home.aanet.com.au/nistune/docs/NIStune_FAQ.pdf

Cheers

It's a really nice bit of kit and I have been following it's development for the past 12 months.

it is a really good alternative to a PFC. I helluva lot of work has gone into it.

[CEF11E]

With any hi-flow you'll be choking the engine at about 5500rpm and the power will drop rapidly; as the turbo can not flow enough gases. Just letting you know, in case you wanted to rev the engine to 7500rpm .

As expected tiny exhaust housing will do that. its a bit of an upgrade path. but thanks for the heads up, I am thinking 3040 or gt35r further down the track

[Al]

Fair enough.

I just bought a GT30R for my 25/30, as i like the response for motokhanas. But i just recently saw a graph of a 25/30 with a GT35R and i am starting to doubt my decision .

I someone (*cough* Joel *cough*) pulled his finger out, fitted their GT30R and posted the results, it may put my mind at ease .

Does anyone have a dyno graph of a rb25/30 fitted with a GT30R?

(Michael maybe?)

[Roy]

Im not sure about others but from what I've seen the big single makes all its boost at an earlier rpm than 2 similiar sized twins.

So thats lag.

Response; once there's enough exhaust gas to bring both the big single and twins up on to lets say 1bar.

Put the foot down; the 2 smaller twins with less inertia are able to spin quicker up to speed and accelerate off. More so noticable in the lower less load gears.

Thats my understanding behind why Nissan went twin parallel turbo's, offer the best response when accelerating out of corners.

Having gone for a ride in a fair few GT-SS or 2530 GTRs i can honestly say they feel a little boring. They ramp onto boost nice and soothly with no real big hit of torque. Singles makign the same power seem to make the same power, but the torque hits harder with a steeper gradient as it ramps onto boost. Im all for the singles myself as you get brother gate. But twins do seem to be the less nonsense solution ...well at least the cars i have been in . LOL i need ot move to SA to feel the single RB30 love

[r33_racer]

look around ive posted the dyno graph here before. Probably both...before WI it was 320rwkws...after was 370rwkws.

Imagine a nice 45 degree looking line pulling all the way to redline. Al just do a search for me or something its either in here or in the rb30 thread. Actually it will be in the rb30 power thread.

[CEF11E]

My head arrived today. complete RB25DE from R33 with VCT. 100% complete except for injectors and fuel rail.

I took the cam covers off and the head is a clean as a whistle.

Would someone be able to confirm a few things for me. please bear with me, I am 60 pages of the way there

I have taken a pic of the front of the head and highlighted the area I believe to be correct. Is it OK to tap a M8 or 10 thread and put a grub screw in here instead of welding? locktite would hold it in place. then drill in the front of the head that lines up with the gallery and tap a fitting in that will be supplied from the OPS. I have read the thread and am about to go ahead with these mods and just want 100% confirmation before I bugger the head

Also what to I do with the other gallery highlighted?

[Spoolup]

The R34 NEO head requires the same mods to the water and oil galleries as the R33 head. It doesnt however require any mods to the front cam bearing oil gallery as its internal gallery runs the full length of the head.

The comb chambers are smaller so piston choice is critical and limited to achieve a good compression ratio.

I too have a R34GT Four and plans are underway for a RB30 conversion using a Pro engines adaptor. They are a cheap 4wd option with all the mod cons - a cheap R34 GTR basically - after a few suspension mods :-).

Hi, like everyone has said bloody great thread, im only upto page 60 or so but give me a week and i'll be up to date

I've decided to jump to the last couple pages to see if anyone has discussed using the r34 neo head so i've just go a quick couple of questions. I've read the rb30 DOHC guide and it says that the water/oil galleries are different in the r34 head and the head has less cc's at only 50cc.

So...

1. Has anyone done a rb30 neo conversion?

2. How different are the galleries? What needs to be done compared to the r33 head?

3. What is the compression ratio with the r34 head like?

I have a r34 gt-four (you would of never of guessed with my user name haha) and this is looking very attractive, i also realise that an adapter needs to be bought to fit my sump onto the rb30, but its been done before with the r32 & 33 gts-4's so it shouldnt be to hard

thanks

[Craved]

My head arrived today. complete RB25DE from R33 with VCT. 100% complete except for injectors and fuel rail.

I took the cam covers off and the head is a clean as a whistle.

Would someone be able to confirm a few things for me. please bear with me, I am 60 pages of the way there

I have taken a pic of the front of the head and highlighted the area I believe to be correct. Is it OK to tap a M8 or 10 thread and put a grub screw in here instead of welding? locktite would hold it in place. then drill in the front of the head that lines up with the gallery and tap a fitting in that will be supplied from the OPS. I have read the thread and am about to go ahead with these mods and just want 100% confirmation before I bugger the head

Also what to I do with the other gallery highlighted?

I had my mechanic put in a grub screw in the vct oil feed. so yes you can do (though i havent assembled my rb30 this has worked for Majanals drift car)