Jump to content
SAU Community

Recommended Posts

now ive beer reading this thread for about 3 months and looking at what u have been doing.

i have a vlt with 250 rwkw just a rb30et

and a r31 with a rb25de 119.7rwkw

i did all the work my self.i have another rb25de coming from just jap and was wondering ifd its worth the hastle of converting to dohc for my vl.

like how easy is it to make lotsa power cos i would want more than 300 rwkw due to the power my curent setup. now is is posible with na cams?

also if i replace the cams do i just have to replace just the shims.what lifts do u get and what kind of overlap do u have with the tommi camshafts.

my vlt is fairly lumpy and i like the sound of a engine that has afair duration camshafts, i know the vvt wil be a issue but is there anyway around this.

Link to comment
Share on other sites

Sydney Kid What exhaust houseing size on the gt35/40 did you use in the following setup? and have u got any dyno pics?

Cheers

Jon

[There were very few "brand" name parts used;

Standard RB30 block, crank, water pump, oil pump and balancer

Balanced up & down and round & round bits

O'ringed block and double annealed copper head gasket

ACL Race Series pistons, rings and bearings

Pistons were ceramic coated on the crowns and oil retention coated on the skirts

Argo I beam rods with ARP rod bolts

Std VL RB30 Commondoor gaskets and seals

Fabricated sump with wings and baffles

ARP studs for cylinder head and main bearings

Std RB26 Camshafts, valves, retainers and followers

Performance brand valve springs

Adj camshaft pulleys (no name brand, early Jun style)

Gates cambelt

Ported head with polished and matched combustion chambers

GT35R on a no name high mount manifold with a no name (HKS copy) wastegate

850 cc Cosmo injectors

Bosch 044 fuel pump

Nismo regulator on the standard fuel rail

Power FC

PWR intercooler

Q45 AFM

Run in on the dyno for around 1 hour all up, change oil and filter and get into it.

Calcs..........

632 bhp = 472 kw less ~60 kw (2wd) = 412 rwkw

The average power from 4,000 rpm to 7,000 rpm is massive and it's not straining at all. A/F ratios are not over 12 to 1 anywhere and the knock is less than 20. Cams and a bit more airflow (no more boost required) it would make 500 rwkw easily]

Edited by kastin
Link to comment
Share on other sites

Heyall just about got through the hole 199 pgs of this topic and by the look's of it there is a hole lot of different combo's you can do with different yr head's and so on. I'm looking to put a 3 ltr in my 91 R32 GTR. Will it work??? And is it worth it. ??? The car is currently making about 250 rwkw. It goes alright but more power is always better. (My Stinking old Falcon ute goes Harder).

I'm looking at hopefully getting up around the 550 600hp mark. Am I dreaming or not??? Where is the best place to start. (Apart from getting the engine).

Any feed back would be great.

Link to comment
Share on other sites

It will work fine. You will need a 4wd sump adaptor.

I think its worth it, with a set of nice rods, pistons, full crank snout and possibly if you can stretch an aftermarket harmonic balancer it will rev like buggery and reliably.

A balancer 'may' not be needed for reliability at high rpm (7500rpm+ or there abouts) providing you run the full oil pump drive crank collar. I don't really know to be honest, maybe some one else who has played can enlighten us.

Best place to start... Finding a good rebuilder that has had plenty to do with the rb30's in the past; the rebuild is likely to be cheaper and more reliable.

Pick up the phone and start making a few phone calls. :D

Link to comment
Share on other sites

It really depends what you want out of the car and its one of those things where you really need to feel how the 3ltr transforms the car. The mid range is simply awesome and mate that with 4wd, its unreal. I could never go back.....

To put it in perspective.

A stock rb25det making 190rwkw odd (12psi) running the usual pfc, fmic, exhaust.

An rb30det running a gt35r .82 (18psi) at no point makes less power anywhere down low (2500-3500rpm) than a rb25det even though the rb25det still runs its stock small quick spooling turbo. :D

So essentially it lunges off idle better than an rb25 then feels like an rb25 from 2500-3500rpm then it snaps and turns in to a monster. Pretty damn good for such a big turbo.

Link to comment
Share on other sites

for 550rwhp i'd be sticking with the 2.6ltr.

No need to go to the addes cost/effort when the 2.6ltr already does an exceptional job with lowmounts

Just my thoughts though :)

I have considered sticking with the 2.6 but I'm a little bit old school and have alway worked with if you want more power/torque, you need more cube's. I also don't really want to blow the origianl block up. 3 ltr block's are a dime a dozen so you can keep busting them and it's not really a huge problem.

Edited by GTROB
Link to comment
Share on other sites

Sydney Kid What exhaust houseing size on the gt35/40 did you use in the following setup? and have u got any dyno pics?

Cheers

Jon

[There were very few "brand" name parts used;

Standard RB30 block, crank, water pump, oil pump and balancer

Balanced up & down and round & round bits

O'ringed block and double annealed copper head gasket

ACL Race Series pistons, rings and bearings

Pistons were ceramic coated on the crowns and oil retention coated on the skirts

Argo I beam rods with ARP rod bolts

Std VL RB30 Commondoor gaskets and seals

Fabricated sump with wings and baffles

ARP studs for cylinder head and main bearings

Std RB26 Camshafts, valves, retainers and followers

Performance brand valve springs

Adj camshaft pulleys (no name brand, early Jun style)

Gates cambelt

Ported head with polished and matched combustion chambers

GT35R on a no name high mount manifold with a no name (HKS copy) wastegate

850 cc Cosmo injectors

Bosch 044 fuel pump

Nismo regulator on the standard fuel rail

Power FC

PWR intercooler

Q45 AFM

Run in on the dyno for around 1 hour all up, change oil and filter and get into it.

Calcs..........

632 bhp = 472 kw less ~60 kw (2wd) = 412 rwkw

The average power from 4,000 rpm to 7,000 rpm is massive and it's not straining at all. A/F ratios are not over 12 to 1 anywhere and the knock is less than 20. Cams and a bit more airflow (no more boost required) it would make 500 rwkw easily]

Ah the old RB30, used it in the car once and then someone paid me enough for it so I could build a bigger and better RB31DET. The GT35R had a 1.06 A/R turbine, with the T4 flange. The compressor A/R was 0.70. Boost was ~1.7 bar (25 psi), the dyno graphs went with the engine as part of the sale.

The limiting factor with that engine were the camshafts, it really needed something bigger than the standard RB26 cams. Then I could have ported it a little better and run a slightly higher compression ratio. The RB31DET has more capacity, JE pistons, gapless rings, 272/10.3mm Jun cams, Jun camshaft pulleys, Jun valve springs, N1 oil pump with crankshaft collar, ½ mm bigger head studs and a GCG T04Z “special” turbo with a Tial wastegate. The sump on the old engine was a “recycled” bottom half, adapted to the RB30 standard sump upper half. It only had 2 one way doors, smaller wings and a rough windage tray. The RB31DET has a brand new High Energy full circuit race sump, with large wings, baffles, 4 one way doors and a proper directional screen windage tray.

I am not looking for any more max power, just lower boost and more throttle response plus another 500 rpm on the useable rpm range. Best part is it’s nearly finished, we have a race meeting this weekend then next week I am into finishing it.

:) cheers :)

Edited by Sydneykid
Link to comment
Share on other sites

for 550rwhp i'd be sticking with the 2.6ltr.

No need to go to the addes cost/effort when the 2.6ltr already does an exceptional job with lowmounts

Just my thoughts though :whistling:

Except when you kill the crank in your RB26 and have to fork out for the new one etc...

I like the RB30 bottom end for how cheap the parts are while making good power.

Link to comment
Share on other sites

so what turbo would be beter on a rb25/30 a, gt 35r .82 or a gt 35/40 .86 (i think) im chasing 350 rwkw or so and am leaning towards the 35r but im a bit unsure.

what are ppls experiances with them. i know that off boost responce will suffer abit but this is not an issue, has any1 else got either of these turbos on there cars and what results do u have, like what revs do they spool and what inlet manifold are u using with them

does any1 have a g-ready plenmum with either of these tubos, and if they do did they notice any diference in spool time between the std long runner inlet manifold and the short g-redy1.

thanks

Link to comment
Share on other sites

I do gt35 .82ar & Greddy Plenum...and i dont think the manifold makes any real world difference. However it makes changing spark plugs easier, unclutters the bay, makes fitting the rb30det so much easier, as there is no worries with height issues:)

I maybe wrong but i think those two turbos are the samething arent they, just people use the two different names to describe that particular turbo. Ones a old name and the other is the new name??

Link to comment
Share on other sites

I am rebuild my motor as some of you might remember and I am going to put an rb30 block on an rb25 head. Anyway, I am getting everything done and I am curious to find out what are the best parts to put in her.

I am not out to buy the most expensive brand named parts simply cause of their label, I just want something that is affordable and that will work. I have tried looking on SAU but being new to the game I am a bit lost. The motor I want to be good for around 600hp at the fly.

Do you know what parts I should get for this amount of power? I have a mechanic getting a quote for me but I want to be able to know what he is on about. I only know the main parts that need replacing.

Pistons =

Rods =

Cams =

Oil pump =

Fuel pump =

Injectors =

Also ARP rod bolts, ARP main bolts, ARP head studs.

Should I be getting more springs/valves etc for that amount of hp? Sorry, but I am new to this and don't even know if I am making any sense, let alone an ass of myself.

Phee

Link to comment
Share on other sites

Alrighty phee your on the right track, but i hope i can help you some more. Also read the RB30 DOHC Guide, found at the bottom of Cubes's post.

First the bottom end. For that sort of HP, i was told to go for argo rods. This being they can and will stand up to the HP ur looking for, and also the torque you will get form the rb30 bottom end. Next is bearings, all you need is the ACL Race Series bearings. Pistons, i cant remember what ones were the "best" but will update when i can find that out. Also yep, ARP rod bolts, ARP crank stud bolts (AKA main bolts) ARP head studs.

Oil & water pump, SydneyKid said to use the gtr N1 oil & water pumps, & the JUN oil collar adapter for the oil pump.

Depends on the use of the car will determine the type of cams you go for, and this will also determine if you need to go to aftermarket springs. As an example, for my car (rb26/30 in 32 gtr) i'm using it for circuit work and am using JUN 264 duration 9.25mm lift IN, JUN 272 9.25mm lift EX. Thus i dont need to upgrade the valvetrain because im not running lift over 10.5mm.

Fuel pump wise i did some research and was scared by the amount of failures of one pump and then that causing the engine to lean out ending in a rebuild with the use of 2 or more inline pumps. So i went for a single SX 1000hp pump.

Injectors, 750cc's be enough? or to be safe, just get some 800cc's.

You'll also need to look at the machining side of things. Work i'm getting done is the exhaust port is getting re-profiled, manifolds getting match ported to the head, external oil return to the sump (from back of head from one of the welsh plugs, into the sump) and the oil galleries modified (dont ask to what extent, caus i dont know :D).

Now that should give you a bit more of an idea of what ur up against.

Hope you have fun with it, and if you need to know more, dont hesitate to ask.

cheers

Shane

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Much less twat-tastic. CF wheels are too garish for civilised use.
    • From there, as the manual says....assembly is the reverse of disassembly, no tricks worth mentioning Much better (for me)
    • In my case, the standard wheel I had was in good condition but the buttons had more wear, so I swapped them across from the original wheel from the car. The plastic rear cover is held on by 4 tabs, and once the wiring is removed you can get access to 2 screws on each side the hold the buttons in From there I just swapped the wiring over. What was interesting is the standard style wheel is 2.0kg but the carbon fibre one is 50% heavier at 2.9kg. It even has a weight inside the wheel at the top to make up for some sort of imbalance in the design. weird
    • Once the airbag is off, to remove the steering wheel.... Undo the 2 plugs into the clock spring, and the horn connector from it's clip. Hit the 19mm nut with a rattle gun (preferably) or if you don't' have one, you probably want an assistant to hold the wheel in place while you use a breaker bar to undo the nut Then, screw the nut back on 3 turns, and pull the wheel sharply towards you. If that doesn't work hit it medium force with a rubber mallet on either side, or possible behind if you can get there. If that all fails (it shouldn't!) you might need a steering wheel puller
    • So, to next task....the carbon fibre steering wheel was either an expensive factory option or a chinesium special. Either way, I don't like either the flat bottom or thick ring style, so it had to go So...to remove the steering wheel.... First, disconnect battery negative and stomp on the brake pedal for a few seconds. Then, remove the small circular covers on each side of the wheel's rear surround to uncover the airbag clips. You need to push something like a flat bladed screw driver through, to push the steel clip inwards and pull the side of the airbag forward. Once you've done the easy side, same on the centre console side. You can see the tab you are shooting for circled in red Then, disconnect the horn spade connector and for the yellow airbag plug you need to get something small under the black locking tab to pop it out, then the connector releases......airbag is off  
×
×
  • Create New...