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I have a bit of a question for those using R33 VCT heads.

I think I already know the answer but confirmation would be great.

If you were to remove VCT would you be able to remove the VCT solenoid and replace it with a fitting that supplies oil to the head? and if so what position would this leave the intake cam in if you retained the original VCT wheel?

sorry if this has been asked before but i really need to know and don't recal seeing anyone doing this before. it would be a no fuss alternative to tapping into the galllery below.

CEF11E,

In the rb30det guide I've included cam specs from somewhere.. I think it was tomei.

You'll find the cam centrelines in there.

The VCT picks up around 10rwkw through the mid range. Less if you dial in the inlet cam appropriately but it does slightly affect the top end.

hey guys im also looking at spool rods and cp pistons i know the cp pistons are awsome gear but i have be told the the spool rods need to be slightly (modified) machined or reshaped slightly to suit the bearings or journals properly, is this true or just BS only reason i am asking is that a well known engine builder on sau has told me of this so i dnt think he would lie but what are your thoughts on this one guys?

thanks for the info Cubes :mellow:

If anyone can help me out with this little pickle...

I am really trying to get my head around VCT and really need to know exactly how it works. I understand the mechanics of it just not what state it is in at what RPM.

please take a good look at the diagrams below. this is my understanding on how it works.

1.jpg

In the above picture you can see there is no oil going to the cam wheel. I pulled out the VCT solenoid and applied power to it and have observed that the holes furthest in are BLOCKED OFF when power is applied making it a normally open solenoid.

2-1.jpg

In this picture you can see that oil IS going to the cam wheel. this happens when there is no power applied to the solenoid.

What I need to know is, What will happen if i remove the solenoid alltogether. will the cam be advanced 20 degrees all the time?

please only comment if you are sure.

there is a problem with the original oil supply I have tapped and i would prefer to block it off, remove the VCT solenoid and supply oil into the hole it screws into if possible. It took me a while to draw this :ninja: so please take a moment to think about it and help me out if you could!

thanks

Hey guys,

For starters this thread is awesome! I am hopefully about to take the plunge and start my RB30 hybrid build

now first things first I aint made of money so it will be a work in progress I plan on getting started by purchasing the block and getting it rebuilt with forgies and the usual this is where my first question comes into place:

I love the idea of the 26/30 but not sure yet if funds will permit goin the 26 head so i will have to wait and see, now what i need to know is will this have any impact on how the bottom end is done? What i am hoping to do is get the block happening and then once thats done work out if the bank will allow the purchase of a 26 head or run my current 25 head.

Question 2: Is there going to be any dramas running the RB25 PowerFC with the 26? What needs to be taken into consideration here?

I notice most people go down the big single route is this the best option? Seems like many differing oppinions on the twin setup / what twins would be suitable for such a beast of a motor? Thinking something along the lines of the GT28-35's as i think they are what a friend has in his gtr and its light switch style delivery on the 26 bottom end.

Thanks in advance,

Dan

Hey guys,

For starters this thread is awesome! I am hopefully about to take the plunge and start my RB30 hybrid build

now first things first I aint made of money so it will be a work in progress I plan on getting started by purchasing the block and getting it rebuilt with forgies and the usual this is where my first question comes into place:

I love the idea of the 26/30 but not sure yet if funds will permit goin the 26 head so i will have to wait and see, now what i need to know is will this have any impact on how the bottom end is done? What i am hoping to do is get the block happening and then once thats done work out if the bank will allow the purchase of a 26 head or run my current 25 head.

Question 2: Is there going to be any dramas running the RB25 PowerFC with the 26? What needs to be taken into consideration here?

I notice most people go down the big single route is this the best option? Seems like many differing oppinions on the twin setup / what twins would be suitable for such a beast of a motor? Thinking something along the lines of the GT28-35's as i think they are what a friend has in his gtr and its light switch style delivery on the 26 bottom end.

Thanks in advance,

Dan

sarp foo'

1) yes the head choice will affect the bottom end work in the piston selection. You have to chose the pistons to suit the head. Going a single in my opinion is better because u have only half the amount of items needed to be purcahsed, saving both money AND weight. Depends what HP u want to get out of the motor, will determine what turbo you need. (also factors like cam selection and headwork will affect that too)

2) Apparantly gtrgeoff is using a 25 pfc with his 26/30 conversion in his gtst, so best to give him a pm and find the details (i think its just a coupe of sensors need to be changed)

sarp foo'

1) yes the head choice will affect the bottom end work in the piston selection. You have to chose the pistons to suit the head. Going a single in my opinion is better because u have only half the amount of items needed to be purcahsed, saving both money AND weight. Depends what HP u want to get out of the motor, will determine what turbo you need. (also factors like cam selection and headwork will affect that too)

2) Apparantly gtrgeoff is using a 25 pfc with his 26/30 conversion in his gtst, so best to give him a pm and find the details (i think its just a coupe of sensors need to be changed)

Well that really rains on my parade then! I know you have a spare head dont you what you want for it - i dont have any morals mabye we could work something out?

Yeah I remember reading that he had done it, will have a search throuh his posts before i pm him

Thanks!

Yes, I do. Well done Shane you are paying attention mate :dry:

I am running a single Z32 AFM as my power goals aren't that extreme. If I do need to step up the grunt then I'll go twins and use an SAFCII or whatever the hell it is to combine the inputs, I'm no expert on that thing though so it could be one of the others. Then of course in the FC Datalogit you can log the output and tickle the ramp rates and the load spread to get better control.

I do have a custom 1-2 pipe setup to allow a single so if you go twins the SAFCII is probably the easiest.

The sensors that needed playing with were the O2 sensor, I extended the loom and plugged it in after the Y pipe join for twins but a single avoids this, and the water temp sensor which has a different voltage output, or at least the one in my head setup did so hang onto your water temp sensor just in case.

Does anyone have info/pics on the pulley setup for a single stage external oil pump?

i'd assume its the same as a dry sump setup. what info u want?

i modified my aircon bracket to take my pump. you'll need a pulley attached to the harmonic balancer bolt, and then when u mount ur pump, get a belt made to ur tooth pitch/width and length.

Anyone welded on fittings for the breathers on the cam covers?

just wondering if there wil be any clearance issues with a 90 degree speedflow fitting off the cover

EDIT -- this is for rb25det and rb25de/rb20 covers

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