R33 Rb30 Conversion

[Ender]

Alright, has anyone in melbourne done this mod and conversion in Melbourne who would let me come over and have a quick look and chat about it......

Thanks if you can spare the time.

Cheers,

Russ

[Skyrine-Dave]

what are those of you with R32's or R31's doing for a gearbox?

is anyone going to keep the Rb20 box or is the only alternative to fork out the cash for the RB25 box?

[lowlux]

im keeping my rb20 gearbox in till it dies

[Skyrine-Dave]

i read somewhere that twin plate clutches? plus Rb20's = instant problems ... is this true

what sort of clutch would be good to use with the RB20 box to handle the extra power?

thanks

Dave

[Clint32]

some power plus some grippy tyres= destroyed RB20 gearbox

Any decent clutch will see out a rb20 gearbox, i have been running a extreme h/d with ceramic clutch plate for along time with 234rwkw and it had handled the power well. I recently fitted a GTR mechanical LSD to the rear of my car and took it too the drags after i put some decent tyres on the rear the gearbox has almost killed itself.

My conclusion is 200+rwkw rb25 gearbox and over 250rwkw twin plate clutch should be used. Will be picking up my rb25 box tomorrow for $1200.

[Steve]

Originally posted by Skyrine-Dave

what sort of clutch would be good to use with the RB20 box to handle the extra power?

One that slips..hehehe. Power always looks for the weak link, upgrade the clutch and it will move down the drive line. I would say in Clints case it was probably the tyres, therefore when the new tyres went on, the gearbox took pole position.

[Cubes]

Apparently even with 200rwkw even if you slap a set of nitto's or even slicks a standard RB20DET gearbox will pop.

Keep the tyres nice on the street and it should be fine for a little while.

[B-Man]

Hey Guys,

I'm thinking more seriously about the RB30 block for my immanent re-build.

My concern tho is the height added by the RB30 block, as I read previously in this thread, the bonnet just closes.

I have a custom plenum on my car, and we had to manufacture a bit of a hole in the sound proofing stuff on the underneath of the bonnet, so the plenum wouldn't rub. So if the RB30 block raises the whole height of the engine, I think I would have a bit of a problem ??? What do ya reckon ??

(The bit that rubs is the throttle body <-> plenum flange)

[Steve]

you could try putting a 30mm thick piece of polystyrene foam on top of the plenum - that will give you a good idea of where the problems may be?

[Cubes]

If the strut brace fits then so will the extra 30mm deck height. However with the RB30DET motor the strut brace will have to be removed permanently.

[TasGTR]

Ender

Try here for some more info. May help.

http://trinity.frontierisp.net.au/~rowan/twincam.htm

[Guilt-Toy]

Ok.

I want to do it cheaply also.

So when will we be able to see pics of the parts / setup to get VCT working & get the cam the oil it needs at the same time?

You guys are talking about rb25DE heads what about a R33 gts25t converstion ? what compression ratio will a RB25DET head on a RB30 block with standard NA pistons be ?? what will it be ? will it work ??

If you buy a good RB30 NA could you get away without rebuilding it ? Why does it have to be rebuilt when these engines go for half a million k's without any troubles ?!?

Will the oil lines / water lines off the turbo have to be modified because of the difference in the block lenth ? and how much longer is it actually ?

I wonder if my Nizmo strut brace will fit..... Anyway are we working on a full guide for this conversion using standard R33 bits ??

[Sydneykid]

Hi Guilt-Toy, You asked .................

**what compression ratio will a RB25DET head on a RB30 block with standard NA pistons be ?? What will it be ?

Compression ratio will be 8.3 to 1

***will it work ??

Yes, did it 5 years ago, made 475 BHP on a small turbo.

***If you buy a good RB30 NA could you get away without rebuilding it ?"

Shoot, for a few hundred bucks for a set of rings and bearings and a balance, why the heck wouldn't you?

***Why does it have to be rebuilt when these engines go for half a million k's without any troubles ?

Is it worth the risk, spend a few hundy refreshing it and feel safe. Or spend a few hundy pulling the engine back out again when something is wrong.

**Will the oil lines / water lines off the turbo have to be modified because of the difference in the block lenth ?

The block is the same length, so they fit straight up.

**and how much longer is it actually ?

The block is the same length, it is around 30 mm taller though.

**Anyway are we working on a full guide for this conversion using standard R33 bits ??

You have got to be kidding. This is so simple. What I do is put an RB30E on one engine stand and an RB25DE (or DET) on another engine stand. I unbolt everything from the head gasket up on the RB30E and throw it away That leaves me with an RB30E bottom end.

I then unbolt everything from the head gasket up on the RB25 and bolt it onto the RB30E bottom end. I then bolt the RB25 oil pump, water pump, harmonic balancer and sump onto the RB30E block. Drill and tap the holes for the cambelt and tensioner and stick on the belt. Then bolt up the RB25 flywheel and clutch.

All finished, takes about 6 hours, and I'm slow.

Hope that helps

PS; My N1 strut brace fits fine.

[GiJOr33]

my understanding is that the RB25DE head is the same as the RB25DET head, but with different cams. It will work with the RB25DET head but it's cheaper to get an RB25DE, plus it means you can have the whole engine ready to swap into the car. You don't have to spend time taking apart the other engine. And if there is something wrong with the head, then your car is undrivable. The main reason for reabuilding is that you may as well while the engine is out of the car. Means that you know everything is in good order before you put it in the car. The water lines/oil lines may need to be modified, but that won't be a big deal. If you use an n/a RB30 then you will have to drill the holes and tap them.

I think the R32's are the only ones that have trouble with having the strut brace... but someone that's done the conversion will say for sure

I'm gonna be taking photo's of everything i do, and also documenting it all.

Edit: Looks like Sydneykid finished his explanation before me!!!

[JNR24]

**Anyway are we working on a full guide for this conversion using standard R33 bits ??

Yep coming allong VERY nicely! =)

Cause of all this good shit in here! so keep talking guys.

The guide so far covers:

-Heapes of comparison photos of RB30 vs RB25 vs RB26 parts. (oil pumps/water pumps/flywheels/cranks/flywheels etc)

-Compression Ratios with diffrent combination of pistons E.g (RB30 DET vs RB30NA)

-What belts & gaskets to buy

- how to retain VCT (step by step with photos)

- Price guide (everything broken down)

- Installation of the motor.

- Cooling comparisons (Stock Oil & water coolers) Effectiveness VS Cost

- Fuel system (Pumps/ injectors / rails/ regs)

- Computers (Best to suit this conversertion (availability, tunability & price all kept in mind)

- Photos photos & more photos!!!

Its practicly a picutre book!

7 rolls of film so far, only about %65 through the guide! =)

[Sydneykid]

Hi guys. Matlowth's at 320 rwkw is the most powerful I have heard off with a standard AFM. We usually see max voltage at 260 rwkw. Although the max voltage normally occurs at the max torque rpm first, not the max horsepower rpm. I would have no real problems tuning at airflow past max voltage, it just requires a bit of extrapolation of the RPM and TPS maps. It is more accurate (and safer) to have some resolution though.

The 320 rwkw would normally see us reaching max voltage on a Z32 AFM. In fact I have a rule of thumb that says if we are aiming for more than 300 rwkw, I go straight for the Q45 AFM.

Hope that helps

[Guilt-Toy]

OKay.. So now all i am waiting for is details to keep VCT & proper oil feed to the head.

Keep up the good work people!

Line on

[JNR24]

These Q45 AFM, were can you them from?

so far i have heard there as rare as rocking horse shite!, and when you do find them they cost big $$$

were do you get yours from?

What motor are they off of? is the motor aussie manufactured?

what car are they out of?

cheers,

Trev

are there any alternative AFMs you can use? besides the Z32 & q45?

[GiJOr33]

Q45 is from the Nissan Infinity 4.6??? litre V8. About the same cost as a Z32 AFM. If you have a Power FC, you can use any that are listed in the AFM Menu

[B-Man]

I have a Hi Flow GCG 500 HP turbo - How would this size go on with the RB30 block ?? Looking to run 18-20PSI