Rb20, Rb25, Rb26, Rb30..... ?

[grigor]

Rb26/30

Sure the Rb26 head bolts up to the Rb30 block, bit of head stud work. But why bother. The Rb25 head flows beautifully, has hydraulic lash adjustment, later models have VVt which you can get to work on the Rb30 block.
The Rb26 head has bucket and shim valve adjustment, great for big RPM, but the stock Rb30 crank isn't happy after 6500 and you simply don't need to rev it anyway to make the power.
Plenum on the 26 is the duck's nuts but the 25's still works very well.
I love the idea of 2-turbos, but on someone else's car. It's bloody crowded down there.
Modern single installations have bugger all lag and more power than 2WD can get to the ground.
For some info on just what stock Nissan block, pistons etc can handle, check out RIPS at Skylines Downunder.

 

[Marco-EFIVL]

Well I'm not thinking of forced induction here, but I'm sure twin cam and 4 - valves would make my RB30 motor a hellava lot more efficient. Btw, if the RB30 crank isn't happy beyond 6500 rpm, I'm guessing I could use one from a different motor, I wouldn't need to get a new one machined would I?

 

[4PLAYN]

The RB 26 crank probably will not fit into the RB30, if you are after a good crank thats good after 6500 go for an aftermarket one and place it in there. Make sure that the crank will get over 6500 and still be happy BEFORE you buy it ... (i cannot think of any cranks off hand)

Of course the 2 litre isnt as torquey as the RB30 ... but the RB25DET is by far the best engine for money and has the power and torque. the RB26 is by far a dearer engine to purchase but would happiley pull the VL to a quicker time than the 'RB30DE' or 'RB30DET' that your planning to build,

If your still wanting to build the engine 'RB30DET'
The RB25DET head would and should bolt straight upto it with a few mods to the block (as stated in previous posts from respected members), but to gain a decent amount of power u would need a fairly large turbo.

There are a few ways to look at engines and with each subject has its good engines and its bad engines

Emissions - RB25DET
Power and Torque - RB26DETT
Revs - RB20DET, RB26DETT
N/A - RB30
Economy - All of them depending on how you drive ...

You could also try and be different by going the RB30DE or RB30DET and doing basic performance mods (pod filter, intercooler, exhaust, ect ect) and a bigger displacement block with a smaller displacement head (raising the pressure in the engine a bit) and still have roughly the same power and toque as the RB25DET.

I am going RB20 but creating a RB24 :thumbsup: and doing everything needed for it ... it will be costly but it'll be different so its possible to do anything ... just the cost thats involved that stops most people doing it ...

PS: all in all its your engine, either you like 2.5 litre or 3 litre ... the cost of the RB25 head and the mods to the block and all the stuff needed would be a cheaper option to buying a full front clip to a R33 and going from there ... just depends on how close you are to engineers and how much information you can gain about the converion (RB25 head on the RB30 block)

I hope this helps a little bit ...

Adam

 

[grigor]

Rb's

By the way, you need an Rb25de head(N/A), not a det(turbo) or the compression ratio is way too low.
I think you should go for a drive in some Skylines before you start an engine build.
If it's revs you want, get in an R32 with an Rb20det. You'll soon get sick of changing gears.
Then try a R33 with an Rb25det. The extra low RPM torque is immediately obvious due to it's extra 500cc but mainly to the variable valve timing. You can drive around at 60 in 5th and still pull away in traffic.
You'd be lucky to drive an Rb25/30 but any engine that can make 100rwkw by 2000RPM is pretty cool, and it will then pull away to an easy 300rwkw.
If you want a N/A Rb30, leave it as a single cam and spend $$$ on power porting.

 

[bangers]

Well I'm not thinking of forced induction here, but I'm sure twin cam and 4 - valves would make my RB30 motor a hellava lot more efficient. Btw, if the RB30 crank isn't happy beyond 6500 rpm, I'm guessing I could use one from a different motor, I wouldn't need to get a new one machined would I?

why would you want to take it beyond 6500rpm?

 

[Marco-EFIVL]

I get the impression that a stock Rb-30 is as sluggish as **** untill it goes past 3,000 rpm. With a twin cam, 4 valve head on it, it would breathe better at those revs hence it would make even more power up top, not to mention fiddling with the cam timing, she'd run very well. I seriously don't think this is gonna happen though...

 

[Alex Moretti]

How you going mate,
just letting you know that the VL 3litres are identical to the RB30 3litre engines and the only difference is that holden had faulty heads because they made there heads from recycled metal and to save the owner of the VL money the owner of there VL would just chuck on a NISSAN RB30 head....

 

[4PLAYN]

Alex Moretti .... hate to say it but the VL 3 litre inline 6 IS a RB30E lol ...

The VL engine is the RB30E and the RB30E head goes on the vl engine as they are EXACTLY the same lol ....

recycled metal ... i thought the head was made out of alloy ....

Holden couldnt make the V6 engine fast enough so they did a partnership deal with Nissan to use their engines in the VL model. the V6 was originally ment for the VL (or so i been told, correct me if im wrong please)

The VL Commodore has the basic styling of an R30-R31 skyline ... (except the 2 door version ofcourse)

still correct me if im wrong ... always room to learn ... im only telling it as i heard ...

 

[Grantis1976]

The mistake holden made was the position / height of the radiator. It sits too low, therfore, if you dont bleed the air out of the system when filling up, she gets a hot spot, and when the coolant finaly hits it.......CRACK !

There is a number of ways around this, the easiest, is to fit a modified top hose, that has a radiator cap. This way, you top up from there, and because it is the highest point in the cooling system, problem solved.

 

[LthlThrt]

now i know that these engines are for lightweight cars but how would they go in a VT Commodore, as i was looking round to get a bit quicker without going V8 jus yet, because i am still on my p plates.

cheers