Help- Using Rb25det Head On Rb30

[sky30]

r31 nismoid, all the links in the old threads with the step by step pics of the vct no longer work, so can we leave this thread open as a dedicated rb25 head on rb30 thread. jarrod83 can confirm and also cant find required info on this topic.

Hi,

Have searched but cant find any firm advice on using the rb25det head on rb30 block, has anyone using this head left the water gallery that doesnt seal by much as standard and had it seal with no problems?

Also is it necessary to feed oil to the front cam journal if i DONT want to run VCT?

Any one got any pics of a head with external oil feed?

Cheers

[brent32]

This is probably not much use as its only hooked up at one end and the photo was taken on a mobile but anyways check it out.

[jarrod83]

yeh im having this problem aswell finding detailed information on how to do the rb30 conversion with a rb25det head, keeping the VCT working, ive read a good chunk of the big rb30 conversion thread and a lot of the little one n theres lots of brief descriptions on how to do it that arent that useful to me.. are there any detailed step by step instructions or a sequence of pictures that would better explain how its done, also it would seem that the allan reynolds twinvl big pond website that alot of people got their information from is no longer working

Cheers

Jarrod

[Guilt-Toy]

sky, you should move this to the New RB30DET area ?? might get more help there.

[R31Nismoid]

ye moved to the RB30 section.

I dont have time at the moment to find the information (moving house) but i know its there.

The whole cam/journal thing i remember clearly reading maybe 3-4 weeks ago

[nizmonut]

ok here's what ya do.

you will need a brass or stainless T piece with two female and one male entry points, the diameters and thread should match that of the thread and diameter on your oil pressure sender unit located under the intake.

you will need to 1/4 inch steel or similar hose fittings with the same thread and diameter.

a tap and die set with the tap to match the fittings you choose to use.

two hose clamps 1/4 inch

600mls of 1/4 highpressure hose....fuel line will do.

some gasket glue or thread tape.

number all your hydraulic lifters I1 I2 I3....I12 and E1 E2 E3...E12

pull them all out and turn your head up side down so you are looking at the face that bolts to the block.

stand at the front of the head , the exhaust ports should be on your left

the intake ports on your right.

at the front right of the head on the corner there is a water jacket and also a small round oil gallery very near each other.

you will note on the front left(intake side) of your rb30 block that there is no small oil gallery near the water jacket.....this is why at the momment the head is incompatible with the 30 block as these two overlap and will mix oil with water.

with the head still upside down and you standing at the front of it circle the small round oil gallery on the head's face, next to the front right water jacket with a pen and take it to a work shop and get them to tig weld up the hole.. ..

now when it is bolted to the rb30 block the oil and water gallery wont over lap.

you can now use a wider range of rb series head gaskets.

at this point you can choose to bolt the head on now leaving the VVL redundant or do what i did below.

whilst your head is still off now is the time to set up the head for a new oil input for the vvl hydraulic lifters.

if you look where the hydralic lifters sit there is a gallery that runs the lenght of the head on both sides

this feeds the hydraulic lifters, you need to feed this gallery again with oil.

with the head in the same position as above, you will note to the right of where the intake cam seal on the front of the head is there is a vertical rib running down from aforementioned welded hole on face to

just below the cam.

place the rear cam cover on(before you would put the cam pulleys on). this will give you a accurate estimate of how much space you have and at what angle the fitting needs to be at to clear everything.

take the brass T junction with two female and one male fittings with the same thread as your oil pressure sender unit.

you will also need two qauter inch hose fittings , one to fit the T piece and one to screw into the side of the head

screw the oil pressure unit into one of the holes on the T piece and then screw in a qauter inch fitting to the other. screw the whole assembly into the block where the oil pressure sender was.

ensure the Brass hose fitting on the T piece is facing up and forward to the front of the engine once tight in the block.

drill a hole (slightly smaller than thread on the second Hose fitting) into the aforemention oil gallery running up the front of the head near the intake cam. with the tap and die set thread the hole to match the thread on the 1/4 inch fitting.

ensure when drilling that you allow for your rear cam cover to go back on. including room for the hose clamp.

screw in the fitting to the head, link the two via the hose and clamp each end.

now you vvl will operate normally as if it was on its orginal rb25 block.

may i add the series one r33 engines had a oil gallery seperate to that of the series two

the series two shared the right front head bolt hole(larger diameter above the thread) to flow oil up to the head. this is why on the series one gasket the hole is seperate yet on the series two head gasket the head bolt hole is tear shaped.

Edited May 21, 2008 by nizmonut

[Craved]

Few pics of the VCt setups i had saved from the original rb30det thread

[bluegts]

Great thread, I've been needing this...

[nizmonut]

cheers for the extra pics craved, i lost mine not long after doing the conversion.

[VB-]

friend of mine just had his built at a shop, the guy there said nothing was done to the head, that theres no oil feed for the VCT, it was just unplugged.....?

PS was a NEO head

Edited May 25, 2008 by VB-

[Adriano]

friend of mine just had his built at a shop, the guy there said nothing was done to the head, that theres no oil feed for the VCT, it was just unplugged.....?

PS was a NEO head

Hahahahaha, then the guy didnt know what to check. NEO's definately have the same issues as a normal rb25 head. Let him drive it for 1000km. Bet there is a milkshake in the sump.

[VB-]

i think theres more likely some form of miscommunication, but will be checking it soon

[dano4127]

friend of mine just had his built at a shop, the guy there said nothing was done to the head, that theres no oil feed for the VCT, it was just unplugged.....?

PS was a NEO head

that does not sound too good is that NRG's build?

[VB-]

yeah i'm mistaken i think, was ages ago i was talking to the tuner and may have been talking bout something else (R32 RB25 head, for another car)

[Redliner007]

thanks mate,

this is exactly what i needed to as i can get my hands on a r33 head but not a r32 for a 30 conversion. Been searching for this thing for over a week now! and some people can get completely unhelpful when they have their cars running mint.

[a31_drifter]

just been contemplating this build over the last week as i'm in need of more hp in the ceffy and i can't justify pouring money into the '20' as it'll only be capable of so much power and i know i'll want more than it can give me so cheers guys for making the build a lot easier as i was unsure of all that was involved.

thanks, a31

Edited June 17, 2008 by a31_drifter

[dan@db-power]

Hi Guys

I'm planning to be putting a NCVS head onto my RB30 block, and firstly just to say thanks for this thread, it will help a great deal

I'm planning to run solid lifter in mine so I take it that means I don't have to worry about feeding oil to the lifters anymore, so I can skip this stage?

Dan

[bunga]

had my hybrid tuned today the vct seems to float to massive retard under load at 4000 rpm producing loss of boost and no power.

i am thinking the valve timing overlaps and all the boost goes out the exhaust.

did get 140rwkw at 4000 on 15 lb

[rival501]

can i use rb30 N/A block? will it be the same as the turbo rb30 block? or there is only 1 rb30 type? the N/A? thank you, because i dont know much about rb30 and im planning to change the 25 block to 30 block and stay with my 25 head series 2.

[TiTAN]

can i use rb30 N/A block? will it be the same as the turbo rb30 block? or there is only 1 rb30 type? the N/A? thank you, because i dont know much about rb30 and im planning to change the 25 block to 30 block and stay with my 25 head series 2.

There is a 300+ page thread at the top of this section of the forum titled "R33 RB30 conversion" see here http://www.skylinesaustralia.com/forums/R3...ion-t15420.html it tells you virtually everything you will want to know.