Rb25/30 Rb30det Vvt Internal Oil Control

[dantheman88]

I just bought a 32 with a rb30det in it that isn't running the VCT. Now I was just wondering if it would be possible to do this mod while the engine is in? And I'm not sure what size oil restrictors were used so could it be potentially harmful to the engine if I was to start using the VCT?

[dantheman88]

actually I just found that mine has the external oil feed done. but because I have a 32 loom I dont have the plug or wiring for the vct. Guess I need to get a plug from option1 and a window switch for the vct control

[Hardenedup]

Hi JonnoHR31,

Thanks for the reply and advice.

My RB30 is not using any extra restrictors, So what ever the RB30 has in there standard.

I would assume that this is more than enough to cope with the extra supply required.

Thanks,

Adam

[sriver killer]

Still got no vct man. lol anyone want to come out and confirm whether this works or not?

[The Mafia]

Hi JonnoHR31,

Thanks for the reply and advice.

My RB30 is not using any extra restrictors, So what ever the RB30 has in there standard.

I would assume that this is more than enough to cope with the extra supply required.

Thanks,

Adam

I had this - Make sure you have a decent catch can because you're going to dump heaps of oil over 4,000rpm

[gold-3lt]

due to oil being scavaged from the intake cam buckets has anyone felt the need to run different sized oil restrictors to compensate for the loss or is the loss hardly significant?. Anyhow what size oil restrictors are people using on their 30/25's whether it be internaly or externally fed?

[The Bogan]

due to oil being scavaged from the intake cam buckets has anyone felt the need to run different sized oil restrictors to compensate for the loss or is the loss hardly significant?. Anyhow what size oil restrictors are people using on their 30/25's whether it be internaly or externally fed?

TOMEI pump

VCT = 0.6mm

Head has the restrictors blocked and a 0.8mm feed tapped into the oil gallerey on the cold side of the head.

[KiwiRS4T]

I just bought a 32 with a rb30det in it that isn't running the VCT. Now I was just wondering if it would be possible to do this mod while the engine is in? And I'm not sure what size oil restrictors were used so could it be potentially harmful to the engine if I was to start using the VCT?

due to oil being scavaged from the intake cam buckets has anyone felt the need to run different sized oil restrictors to compensate for the loss or is the loss hardly significant?. Anyhow what size oil restrictors are people using on their 30/25's whether it be internaly or externally fed?

I have 2 x 1mm restrictors and hydraulic lifters and my vct works fine.

[MRHD66]

Awesome this is what I want to do to my RB25/30

[The Bogan]

Be aware that works on the street or the drags may not on the track.

With stock VCT restrictor and 2 x 1mm restrictors in the head mine was fine on the street or at the drags but spewed oil on the track.

To control the oil now my restricters are 0.6 VCT, 1 X 0.8 for the head, drilled out oil returns, 2 x head drains or sump vents (if your that way inclined), catch can drains back to sump, even with this it was spitting oil a bit so I got RB26 cam covers with MINES baffles and foam inserts, I head out to Wakefield this Saturday with my fingers crossed.

The TOMIE pump was a problem as the pressure was 120 psi at 6000 rpm, so I got a regulator installed and now it sits at about 90 psi.

If your building from scratch use the R34 RB25? head as its got VCT and solid lifters (best of both worlds)

VCT works great, I disconected it and noticed straight away the car was much slower to come on to power, when I connected it again it came on good again ( well as good as a TO4Z comes on anyway)

Good luck, Mark

[zoidbergmerc]

Excellent thread. Very helpful

[The Bogan]

My main problem turned out being the return to the sump from the front head drain and the catch can was to low on the hot side of tthe sump and oil was being forced up it filling the head thus overflowing the catch can.

Removed front head drain, put a one way check valve into the return from the catch can and increased the restictor size to 1mm.

3 track days and about 6 drag days later and all is fine.

[gold-3lt]

Ok so does this work or not? any proof? who has done it here with success?

[gold-3lt]

Would like to know if it's worth me keeping the VCT or not. I'm chasing 330 kw and want to know if its worth keeping and at which point in the rev range will there be any benefit from keeping it?? looking at running a gt35 82r highmount and external gate.

Basically my options are keep vct and stock cams, delete vct and keep stock cams, delete vct and upgrade cams unless of course i upgrade to cams which still support vct.

What are peoples experience with 300+ kw while maintaining VCT?

[jangles]

You want more response, keep vct...

Option 2 is stupid. Option 3 isn't necessary anymore because Option 4 is available.

NYTSKY has over 500kw with small upgraded cams

[gold-3lt]

You want more response, keep vct...

Option 2 is stupid. Option 3 isn't necessary anymore because Option 4 is available.

NYTSKY has over 500kw with small upgraded cams

I agree, option 2 is just plain stupid and a backwards step. I'm after bulk response so i need to look into all my options right now so i make the right choice and don't have to do shit twice..

At this stage i'll be keeping the vct and stock cams which will leave me room in the future to drop in some larger cams which can support vct.

I didnt realise people were still keeping their VCT with power levels more than just slightly above stock. Most seem to jump at the chance to scrap it in the pursuit for more power and high lift cams.

[The Bogan]

My 2530 with stock cams and vct was running over 500 hp.

[KiwiRS4T]

I have VCT stock cams hydraulic lifters and 2 x 1.0mm restrictors - also two sump vents - one to top of catch can and one from bottom as a return (will put a non return valve in the bottom one to make sure it doesn't also fill the catch can). With this setup on the track there is now nothing spewing out. I am of the opinion that the so-called head drain is not only not draining but possibly even a cause of the problem. I don't have one.

[ScreamerNewbie]

hi guys im currently building a 400+kw rb25/30 retaining vct

my head is currently being machined and I need to know what the maximum diameter is that I can drill out the head oil drains?

I have a -12 headoil drain also and restrictors etc but I will be doing the above also, any info or feed bad muchly appreciated

Corey

[SilverECR33]

I've been building one for freakin ages. its finally running again and hopefully tuned next week.

However Im concerned about one of the comments regarding the grub screw. My first head was all welded np. but decided to use a new head this time around but it has been grub screwed this time and tapped. will this be an issue? and how long will it last?