Jump to content
SAU Community

Recommended Posts

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

Link to comment
https://www.sau.com.au/forums/topic/220112-help-using-rb25det-head-on-rb30/
Share on other sites

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

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.

post-50030-1211336309_thumb.jpg

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.. ..

post-50030-1211336351_thumb.jpg

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 by nizmonut

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 by 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

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.

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?

  • 3 weeks later...

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.

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 by a31_drifter
  • 4 weeks later...

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 :D

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 :bunny:

  • 1 month later...

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

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.

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.

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

    • You have found the problem. The wire from the switch to the HB is shorted to earth. Now you have to physically find it and replace it. It won't be the switch, although following the steps above (and yes, where you ask, that is the light switch on the RHS of the binnacle) will rule it out for sure. Or not, if perhaps the switch has melted. But there's no route to earth inside the switch, so I can't see how it would.
    • I did read your post, a few times actually.    Done. Followed this step. [Negative probe should be on the cars chassis. Positive on the wire.]   Did this partially.. now that im reading this over, i only unplugged the LED lights. [Start as said above by unplugging everything (unplug the lights, and switches.] When you are talking about the switch, you're talking about the knob thing on the right side in the drivers seat right? If so, i need to take that apart?  [Now at the switch, there is a wire from the fuse, to the switch, so out your positive on that terminal. It should read open circuit. If it reads something, especially a stupid low value, the short is somewhere between the fuse and the switch.] At this point are you referring to the connector by the headlights?  [If that's fine, now put the positive probe on the wire that goes to the headlight (at the switch plug). If it reads stupid low, the fault is from the switch, to the headlight.] Did this. I can confirm that the LED lights aren't the issue [Another quick test, is take the whole LED light setup from the left, and plug it into the right side, does it still blow the fuse? If you put the right hand side led light setup on the left hand side wiring, does the left hand side wiring now blow?  If the blowing fuse swaps from right to left doing this, your LED lights are the issue.]
    • Hey was wondering if you ended up installing the R33 GTR speed sensor - I found one too and wanted to confirm it's a direct swap into the R34 6 speed?
    • After 23 years of owning a Skyline, finally had the latch go.  Followed this guide,  works like a dream again. Great Guide 👍
    • Hi all,   I’ve got the biggest lot of problems with my R33 GTS-T   It was a freshly rebuilt 25th anniversary RB25DET (plastic cas, neo cams) probably 6 years ago now   The engine was running so well but I fkd up badly and trusted someone I’d known for 10 years that was well known around Plazmaman for his welding and fab work. I added a lovely photo of some of his previous work. Not sure why my car was worked on by whoever did this shit     I’m normally someone who would never open myself up to something like this, I still can’t believe I did it. Trusting him literally fkd it all up for me. Everything has been a struggle, like it’s almost been 6 years that’s how much I’ve just on and off been trying to work it all out.    All I wanted was a car that danced down low, like full boost from around 3~3500rpm to redline, don’t really care what power it puts down (if it ever does) but I just wanted it to be quick to get on it.    He recommended the turbo to get, I picked Hypergear but he told me to get the front 4” with a T4 and 0.68 rear housing.    I was expecting all these beautiful welds, tidy fab work and paid for it to be ready to go to a tuner when I got it back.    I got a car back that was an absolute mess, I actually couldn’t believe it was my car anymore. I don’t think you could even call what he did welds, they’re disgusting.    So I stripped everything he touched off it and with every bolt I loosened it just got worse and worse.    I covered it and literally built and finished another car in the meantime but now it’s getting to the point where I really want my Skyline back.   Its a struggle because I paid him to do all this shit because I didn’t know how to and now I’ve had to try and figure it all out omg    Please excuse the bird shit horrible welds, I’ve got my show pony car and am so beyond dealing with this car I don’t even really care at this point.    If someone told me about what he did to my car I wouldn’t have believed them but it happened to me. It was unbelievable. He went missing, my car went missing, it came back missing parts, the straight af chassis rails bore the scars of being dragged up a trailer backwards, even the sandwich plate was bent. Everything was leaking and open to whatever fell into it, rounded off/ missing bolts, power steering oil and coolant everywhere, no gaskets, parts stolen off it, even managed to damage the sump pan.   Promised me he’d finish the car, knew what it meant to me, I paid him thousands and thousands just for him to trash it. He told me he was fully licensed and insured, come to find out he’d cancelled his ABN, so obviously no insurance. I had laid up insurance on the car and would’ve been covered but I was scared they would’ve written it off or because the business was no longer trading I’d still be liable.    He was supposed to:  New fully custom mild steam pipe exhaust manifold with turbo location moved from factory position to high forward mount. (I don’t know if it is a mild steam pipe, I’ve got a funny feeling the waste gate isn’t in a very good position and I don’t think the outlets off each cylinder are equal) 4” custom stainless steel dump with external gate (he re-plumbed it) Cut and shut OEM intake manifold with throttle reposition (I ended up doing the throttle reposition) Box in pod filter (left out) New 100cel catalytic converter (pretty sure it’s there but unsure if it’s 100cel) Front mount intercooler piping fabricated to suit (all smashed up and rusty holes where he was supposed to make it look standard where fmic piping passes through. I don’t even think my front bar is going to fit 🙄) Custom 5” intake pipe from pod to turbo (didn’t come with it so had to do something to make it work with the Z32 afm)   Engine: Full cylinder head service & machining  Brand new valves Precision upgraded spring kit Engine block honed New bearings  New piston rings  New ARP conrod bolt kit New ARP head studs Cometic head gasket VRS kit   ATR43SS2 ball bearing turbo 0.68 rear housing  Turbosmart 45mm external wastegate (got delivered to the fab bloke, I’ve got no idea what spring is in it, I’m assuming the one that came pre installed) Walbro 260 fuel pump  Nismo 740cc injectors (tested to 880) Spitfire coil packs GCG FMIC RB25DET manual 5 speed 4:11 rear diff   I’ve got an Apexi Power FC in it atm, I was hoping to just get it to operating temp to make sure everything was okay before towing to a tuner but it’s over-fuelling too much. I don’t think that’s going to happen so i think I’m going to get either a Link G4 or Haltech for it. What do you guys recommend? I can’t work out the power FC so just gonna give up on that one     It’s got an exhaust leak coming from somewhere I can’t see 🙄    The fuel pressure was steady but now it like drops from 40 to 20psi randomly (noticed this yesterday)    I’ll attach pics of the shit he put on my car and the engine bay now as it sits    I really just need some help, I need a tuner in Sydney I can trust, I’d like to be with the car while it’s being tuned if possible, I know it looks terrible but unfortunately I’ve just got to put up with it for now and fix the cosmetic stuff later   Do you guys think the manifolds are going to be okay? Or do I throw the exhaust manifold and try again?   I don’t even think these combinations are going to work tbh   I know everything I fitted was rated to be able to take at least 400kW but most rated higher    If you’ve gotten this far I really really appreciate it 🙏 I don’t mind if you trash me or the car, I made a rookie error and f**k I’ve paid for it. As you’ll see 🙄  
×
×
  • Create New...