R33 Rb30 Conversion

[unique1]

who running a GT35R using speed flow fittings put a restrictor in the line to slow down the oil flow? Is this needed?

dont qoute me on this but i was told garrett turbos already have the restrictor built in and its only the hks ones that dont from what a local workshop told me.

[Godzilla33]

might give garrett a call n check it out from the horses mouth I spose, If anyone should know you would think they would. Thought id heard somewhere along the line that you needed to slow the flow down or they can be inclined to puff a bit of smoke.

[xsv_32]

Hey quick question, will an r32 gtr sandwich plate fit between an rb30 block and gearbox??

Any advice would be tops!

[fletch rb30]

Hey quick question, will an r32 gtr sandwich plate fit between an rb30 block and gearbox??

Any advice would be tops!

yep

[xsv_32]

Cool also need to no if rb26 valve springs will fit to the 25de head im using as the factory ones wont hold up with the boost.... Iv heard mixed opinions but i really need a straight answer if possible. If anyone could help me out it would be great

[Cubes]

R33 RB25DE head is a NO.

R32 RB25DE head is a YES.

The R32 rb25de head is very similar to the rb20det head but I have discovered another difference. The Lifters. I'm about to make a post in the FI section.

who running a GT35R using speed flow fittings put a restrictor in the line to slow down the oil flow? Is this needed?

The GT35 and GT30 cores are the same.

I run a restrictor upstream of the core.

Do note Nissan from factory run 2 restrictors; one at the block and one at the turbo.

I simply followed suit as do GCG.

No issues and I've covered around 10,000-15,000km's with the new turbo.

I used the standard nissan banjo that bolts to the block; had the bundy tune sweated off new bundy tube soldered; and then an appropriate 7/16 inverted flare fitting at the end that bolts to the turbo. Cost $38

[Highwayman]

Hi there, Alan is my name and I drive a RB30 "powered" GQ Patrol, circa 1992. In thread #6621 I think it was, the author stated that these engines were "quite old" and finished production in the 80's. Mine is a '92 and I think Nissan carried the RB30'S thru to at least '95. Were the engines in storage for 8-10 years? I, like most of you guys, am looking for more power from my RB30 and so far I am looking at doing a NA version of the twin cam idea. As the vehicle is currently carburetted, I know that I have quite a large project on my hands and an even steeper learning curve. I am enjoying this forum and in time, will more than likely be needing loads of advice. I thank you all in advance, Alan."Old" RB30's

[Godzilla33]

thanks cubes, I got speed flow fittings the other night so ill have to make an inline restrictor to suit, what size did you go for? bout 1mm should do it you reckon?

[Alf]

How much did the speed flow fittings cost?

[Cubes]

thanks cubes, I got speed flow fittings the other night so ill have to make an inline restrictor to suit, what size did you go for? bout 1mm should do it you reckon?

I used the stock nissan banjo but didn't have the tools required to measure it. It looked 1mm or so?

If you still have yours measure the sucker.

Also... GCG when they sell you a new BB GT turbo recommend using a 0.9-1mm restrictor.

Dangerman4 is another who has used a restrictor supplied by GCG with his GT35r .82. He's had his setup for longer than mine and no doubt done more kms as its his missus I mean his car.

[Godzilla33]

will do, think Ive got a mig welder tip that is about .9 - 1mm, just need to machine it to size. The speed flow fittings cost me $220. that was for braided line for oil n water, adapters, 45 & 90 degree oil fittings, three of 90 degree water fittings & a couple of other little adapters.

[daisu]

Hey guys, after doing a lot of reading I'm now seriously considering doing this conversion for my cefiro.

I'm not looking for massive power, but I am keen on making power efficiently, I haven't done any definite calculations but I think 250-300rwkw would be a good figure to aim for.

At first, I was intending on doing it as simple as possible, trying to keep costs down, as I said not looking for massive power. So the original plan was to buy a running RB30E and slap the R32 RB25DE head on. Cheap and simple.

But I figure for a bit of extra time, money and effort, using the R33 VCT head would increase performance and efficiency. So that's the current plan.

Also, in an effort to improve response/efficiency and power I'd like to run higher than the approx 8.5:1 compression ratio.

This either means aftermarket pistons, or decking of the block/head. I wouldn't mind getting aftermarket pistons/rods but from what I've read the standard RB30 bottom end is more than capable of the power output I am aiming for.

Is it even possible to deck the block/head to reach this compression ratio and is it cost effective when compared to aftermarket high compression pistons?

If decking is not an option, will I beable to use standard rods with aftermarket pistons?

What about the cost of replacement (new) standard rods? Is this an option and again is it cost effective?

Also, from the RB30 PDF guide on the front page, it mentions O-ringing the block, but I can't recall it being mentioned in any of the buildups in this thread. What are your thoughts on this?

Now to continue reading...

Edited June 26, 2008 by daisu

[GTRgeoff]

O rings are great for stock gaskets but there are plenty of good metal gaskets on the market now with the O ring design built in in a sense.

As for the rest, you will have to decide on the budget you want to keep. Brad (spoolup) can get you CP pistons to give 9:1 at a good price, plus rods if you decide to retire the Nissan ones.

[daisu]

Yeah I think I'll have to do a few cost estimates first before I decide what I can and can't afford.

At the moment I'm more interested to know if it's possible to deck the block to get 9:1 compression ratio with standard rods/pistons.

Edited June 26, 2008 by daisu

[Adriano]

You probably can deck the head/block to achieve the comp, but you will have to completely disassemble the motor to do so, however to do this, if you ever have head problems, you wont be able to machine the head again. Stock rb30 rods are fine for the power you are after.

[daisu]

Well I'd have the block disassembled anyway to do the bearings etc

What about if I just purchased aftermarket pistons and used them on the standard rods? Good idea/Bad idea?

[unique1]

another couple of quick questions for a rb30/26 setup. can u use the rb30 head bolts with the 26 head as the locating pins will keep the head in position wont they? i am only using stock 30 internals and aiming for low 400hp figures so im thinking it should be good enough? im also using a hks drag metal head gasket as well as i have a couple lying around. whats the stock head gasket thickness? these hks ones are 1.2mm is that too thick?

Edited June 26, 2008 by unique1

[Al]

Engine is now fully assembled and sitting in the car. Just need to wire it all up and run it on the dyno again. Hopefully should have it back next week.

[Roy]

YAY!

R33 RB25DE head is a NO.

R32 RB25DE head is a YES.

The R32 rb25de head is very similar to the rb20det head but I have discovered another difference. The Lifters. I'm about to make a post in the FI section.

So the R32 RB25DE uses what lifters? I have a complete RB26 head that i was going to strip down for its valves, springs and lifters. If i can confirm whether i use Tomei RB20, RB25 or RB26 solid lifters then i will just grab them and use them with the std valves and aftermarket springs.

The RB26 valve is sodium filled for better cooling, any idea what the RB25DE valves are?

[TiTAN]

So it will be out at the next deca?