Front Facing Plenum + 100mm Tb

[Finny]

Hi guys,

This just turned up from Japan (NOT TAIWAN).

So far it doesn't look like I need to modify much, Fuel rail and my 940cc injectors went on nicely, idler and TPS went on fine.

The 100mm TB eats the stock TB like something cronic.

Any one had any experience with big RBs and 100mm throttle bodies... donno how it will effect drivability.

Sorry for the crappy quality, I took the photos on my phone.

Edited June 12, 2008 by Finny

[DJRIFT]

that is very nice indeed. do you mind if i ask where you sourced it? and how much?

i belive that Rob runs a 100mm on his setup and he has it for quite some time i belive amybe from as far back as when he was still single turboed.

i rember them saying it made a much bigger difference than they ever expected.

[Shane_954]

No, rob has an 85mm hypertune. I fitted that when the twins went on so cant really give you an idea of what difference it made.

Are you going to run that dirty old rb20 rail?

Edited June 12, 2008 by shane_180sx

[Finny]

My RB30DET runs an R32 RB25DE head which is basiclly an RB20DET head but with the larger bore so you dont have to modify the hell out of it like RB20 heads to fit RB30E block.

Due to this I had an RB20 intake manifold so this intake manifold it to suit an RB20 head which is extreamly hard to find.

I think I will buy a new rail but I will have to get one to suit and RB20 which I guess is harder to find than RB25.

The intake manifold + TB was $750 US (~$830AU) delivered from JAPAN.

ku_engineering was the user name on EBAY, I messaged him and asked for a custom one to suit RB20 head and to suit a 100mm TB and also including a 100mm TB. For an RB25 you may be able to get them cheaper as they are more common.

Edited June 12, 2008 by Finny

[Dahtone Racing]

RB26 rail will also fit

[Finny]

Cheers, will probably get one soon.

[DJRIFT]

i currently run a rb25de + t engine in my car and have just brought a rb30 bottom end.

what mods did you have to do finny to get it to all bolt up? i have heard that there isnt much to do to get the rb25 de and rb20 to mate up.

i belive hypertune still make and sell a plenum that looks identical to that one for i think $1000. a bloke of NS.com had one for sale a while back and i am kicking myself i didnt buy it. another local blok has just brought and fitted one to an rb20 off hypertune.

[Finny]

Ok......

Correct me if I am wrong but...

R33 RB25DE head is the same as an RB25DET head but I think the cam timing is different.

R32 RB25DE head is the easyest head to use in an RB30DET conversion.

R32 RB20 head... don't bother in Tasmania, there isn't really any engeneers who are good enough to modify it to suit RB30E block.

RB25's and RB30's run an 86mm bore but RB20s are smaller.

R33 RB25 head has VVT were as R32 RB25 head doesn't. This is the main issue with the conversion, you need to tap in oil lines to feel oil to and from the VVT. There is heaps of info on this site on how to do this. From memory you have to T piece the return into your turbo oil drain and tap a hole in the block to run an external oil line to the VVT (have to tap an oil pipe into this as well) you then need to weld up the hole in the head which feeds the VVT.

so basiclly RB25DET block has an oil gallery to feet the VVT but RB30E block doesn't have this so you have to run an external line.

Final task is to fit another tentioner pully to the block. There is also heaps of info on how to do this.

edit:

ofcourse with my R32 RB25DE head bolted strait up it just required the pully to be drilled in, So mine was very easy to do. And who needs VVT any way

edit again:

ok, I just read your "Car(s): R32 GTS-t 4door". If you are running an R32 RB25DE+T your pretty much have the perfect engine for this, litterlly bolts strait up with no modifications, then all you need to do is buy a longer timing belt and drill a new pully in.

I actually have done mine different to how every one has said how to do this because my timing belt kept comming off. Luckely my engine is non-inteference.

Edited June 13, 2008 by Finny

[Shane_954]

If you cant find a rail then build your own, thats what we did on robs car.

[Finny]

my rail is perfectly fine... its just dirty....

[DJRIFT]

Ok......

Correct me if I am wrong but...

R33 RB25DE head is the same as an RB25DET head but I think the cam timing is different.

R32 RB25DE head is the easyest head to use in an RB30DET conversion.

R32 RB20 head... don't bother in Tasmania, there isn't really any engeneers who are good enough to modify it to suit RB30E block.

RB25's and RB30's run an 86mm bore but RB20s are smaller.

R33 RB25 head has VVT were as R32 RB25 head doesn't. This is the main issue with the conversion, you need to tap in oil lines to feel oil to and from the VVT. There is heaps of info on this site on how to do this. From memory you have to T piece the return into your turbo oil drain and tap a hole in the block to run an external oil line to the VVT (have to tap an oil pipe into this as well) you then need to weld up the hole in the head which feeds the VVT.

so basiclly RB25DET block has an oil gallery to feet the VVT but RB30E block doesn't have this so you have to run an external line.

Final task is to fit another tentioner pully to the block. There is also heaps of info on how to do this.

edit:

ofcourse with my R32 RB25DE head bolted strait up it just required the pully to be drilled in, So mine was very easy to do. And who needs VVT any way

edit again:

ok, I just read your "Car(s): R32 GTS-t 4door". If you are running an R32 RB25DE+T your pretty much have the perfect engine for this, litterlly bolts strait up with no modifications, then all you need to do is buy a longer timing belt and drill a new pully in.

I actually have done mine different to how every one has said how to do this because my timing belt kept comming off. Luckely my engine is non-inteference.

yep thats all good.

yea the only reason i am going to do it is because i have the rb25de head off a non VVT model rb25. so basicly all i will have to do is fit up the extra pully mount.

plan is to biuld up the bottom end while still using the car then bolt it all together later.

oh and can i get your old throttle body?

[CATKICKER]

I have an RB26 rail if needed.

[Finny]

I have an RB25DET R33 and RB25DET R32 TB and yeah you can have it.

Its missing TPS though.

[WHITER33GTS-T]

Ive just had a 25/30 built for my 33. I used my 25det head and had to have some of the oil gallaries drilled and tapped in the front of the head. And the oil drains in the head opened up.

You will love the torque from the 30 bottem end. Mine is on boost @ 4000 with the twins. Combine that with a C4, 3800 stall and a 175hp shot of nos and i think it should go alright.

Am looking for a new turbo now. Maybe a GT42R or GT47

[SKiT_R31]

R32 RB20 head... don't bother in Tasmania, there isn't really any engeneers who are good enough to modify it to suit RB30E block.

There are plenty capable, just need to enlarge the combustion chamber etc, the problem is, there isn't much benefit over the 30e head with this modification, only one is the better electrics and twin cam capability (one cam adjustment etc) as standard they have about the same flow as the 30e! You could heavily port it and put in oversize valves etc, but by the time you pay for all that, its cost you way more than just buying an R33 RB25 spec head. You can also just not run the vct at all and use it with 20 electrics.

WHITER33GTS-T, haha pfft, you'll be lucky to pull a 14!

[TazzS13]

do the water pipes line up properly?

and the top radiator hose? you may also have problems with clearance on the thermostat housing at the bottom.

throttle cable long enough? if not source an r31 one

have you got a header tank to bleed air out now the standard bleed is gone which sat higher than the head?

then you just have to extend the wiring on your tps and you should be away.

also I dont know what power your after, but 100mm is a bit overkill

Just a few things to think about good luck with it.

[Finny]

do the water pipes line up properly? Yes

and the top radiator hose? you may also have problems with clearance on the thermostat housing at the bottom.

Nope no problems there

throttle cable long enough? if not source an r31 one

Yeah I need to get an R31 one

have you got a header tank to bleed air out now the standard bleed is gone which sat higher than the head?

Hmm not sure what I am going to do here.

then you just have to extend the wiring on your tps and you should be away.

Don't need to extend this, it plugged up fine :S

also I dont know what power your after, but 100mm is a bit overkill

My current turbo is only good for about 320RWKW TOPS, I am looking at getting this replaced and then going for 400RWKW.

My engine should hold up, my fuel system will support more than this, my Microtech LT12s should love it, gearbox and clutch hopes I don't break too many of them

Just a few things to think about good luck with it.

[WHITER33GTS-T]

There are plenty capable, just need to enlarge the combustion chamber etc, the problem is, there isn't much benefit over the 30e head with this modification, only one is the better electrics and twin cam capability (one cam adjustment etc) as standard they have about the same flow as the 30e! You could heavily port it and put in oversize valves etc, but by the time you pay for all that, its cost you way more than just buying an R33 RB25 spec head. You can also just not run the vct at all and use it with 20 electrics.

WHITER33GTS-T, haha pfft, you'll be lucky to pull a 14!

Yeah i might run a 14 if i back off at half track....

400rwkw is great fun on the street. Thats if you dont like your tyres

As for the clutch go for a Jim Berry race clutch mine held great and never slipped even with 3rd gear cooks (drop clutch in 3rd gear) and even clutch kicks in 4th gear @ 100kph. As for gearboxes I have a 25 box here if you want a spare.

Edited July 6, 2008 by WHITER33GTS-T