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hehe he had no choice, knock levels were reading too high. :rofl:

I don't know Shaun personally but have known of him for quite a few years now, he has tuned quite a few high powered RB's and to date, touch wood, hasn't popped any.

He does get good power out of them also so he does have a nack with tuning. ;)

Ok back to this thread, can anyone help with the following, i know alot of you are using the non-vct heads, but anyway.

How do i tell if the VCT is working, i can't see/feel any difference with it on or off.

Also if i supply 12V to the solonoid on idle, the sound/idle doesn't change in anyway what so ever?

Shouldn't I be seeing something with the extra 10deg advance on the inlet cam, or will 10deg be neglible on the 3L.

i may need to get it on the dyno to prove if its working or not.

Its got a copper feed line from the standard rb30 oil pressure sender hole.

The copper line is small diameter, like boost guage line size in diameter, but this diameter is still bigger than the restrictor hole in the head, which i made 1.2mm from memory, like the restrictor in the rb25 head.

Do i need to get bigger line, maybe a bigger restrictor hole?

Stupid VCT, causes more trouble then its worth, grr........

A LITTLE OFF TOPIC...

However, I thought you guys on this thread would enjoy this..

This is a question that was asked of the AUTOSPEED Crew.

There are so many errors in the reply that I'm starting to think they are getting their answers from their asses...

Question:

Hi guys - I own a R33 Skyline GTS25T automatic and have decided to go for a RB25/RB30 hybrid engine. I have recently met someone who did most of the work by himself on a similar car and managed to squeeze out 345kW at the rears. He uses a massive KKK turbo, custom plenum, and all the rest of the usual goodies. The car underwent an auto to manual conversion and uses a R32 gearbox with fabricated bell housing.

My concerns are, if I go this way, should I use the standard R33 gearbox or go for a S15 6-speed? Would it be better to stick with auto and get a tricked torque converter (like the Trimatic trans used in the SubZero car)? What about a bigger LSD replacing the viscous factory one? And how about plenum design - GReddy v Subzero v Nizpro one? Lastly, I have a mate in Japan who will try to get most of the parts for me - should I consider a RB26DETT head instead? Any suggestions?

Amrit Ram

New Zealand

ANSWER:

The optimal driveline depends on the torque characteristic of the engine you build and your intended application. If you're planning on coming near 345kW at the back wheels you're invariably talking about a massive single turbo and lots of lag; in this case, an auto with a high rpm converter has its advantages. An auto will allow you to stall the engine up for fast launches (it's difficult to launch a big turbo'd engine with a manual 'box without either massive wheelspin or bogging down) and it will also kick-down by itself, making the car feel livelier in traffic. The biggest problems are noise and fuel consumption (lots of revs everywhere you go). Oh, but your standard R33 trans won't be able to hack such huge power - something like the beefed up Trimatic should capably handle the grunt.

We're not sure about the limits of the Nissan manual gearboxes, but we'd imagine they'd be pretty marginal at that power level. A drag-oriented auto is likely to be the more trouble-free approach. With this amount of power you'll need to find the most possible traction using, of course, sticky rear tyres and probably a locker type diff centre. See how you go durability wise using the standard type diff - a tougher unit may be required depending how hard it's treated.

No idea which intake plenum is better - you'd need to compare side by side on a dyno to judge. Any parts from a Skyline GT-R engine are ultra expensive - see how you go bolting all the good gear to your standard RB25 head. If you're not satisfied with the power, you should look into a GT-R head as a final phase.

Ok back to this thread, can anyone help with the following, i know alot of you are using the non-vct heads, but anyway.

How do i tell if the VCT is working, i can't see/feel any difference with it on or off.  

Also if i supply 12V to the solonoid on idle, the sound/idle doesn't change in anyway what so ever?

Shouldn't I be seeing something with the extra 10deg advance on the inlet cam, or will 10deg be neglible on the 3L.

i may need to get it on the dyno to prove if its working or not.

Its got a copper feed line from the standard rb30 oil pressure sender hole.

The copper line is small diameter, like boost guage line size in diameter, but this diameter is still bigger than the restrictor hole in the head, which i made 1.2mm from memory, like the restrictor in the rb25 head.

Do i need to get bigger line, maybe a bigger restrictor hole?

Stupid VCT, causes more trouble then its worth, grr........

You should see a noticable difference in idle. Mine was a little unsteady, just hunting a bit at idle. On the road you should definately notice a loss of power up to 4000rpm with the vct disconnected.

My oil feed is 1/8" bundy tube i think, with a 1.2mm restrictor in it. Seems to work fine.

RB30-Power,

Have you had it tuned? My ECU really didn't like running boost. Mine played up big time, big power dips. Without boost or very minimal. It was fine.

The PowerFC was much better. The Ignition was to aggressive, fueling was fairly close.

Yeah, I can not see any difference at all with it on/off.

i think maybe the oil supply volume is inadequate.

I used a 1.2mm restrictor hole. The depth of the restrictor is probally around 8mm though, i think the restrictor in the block was only around 3-4mm. Wether that will effect it or not, im not sure.

Out of interest, can yoi hear the VCT camgear mechanism engage or is it silent. I can hear the solonoid click with the power, but thats all.

I have only played with it a few hours last weekend.

I put it into my brothers R31.

Anyway he has been driving it the last week, and i wont have time to play with it again until the weekend.

Because its only running 5psi i don't think im upsetting it yet, bit more air flow and might have trouble.

I actually really retarted the static timing, to see if the VCT would make a difference, or mayeb allow me to see a difference, but still couldn't notice anything.

I have the factory 25det ECU at a static timing of 25deg BTDC, with 15 it lost response a bit, haven't tried any more than this at the moment. Doesn't ping at all. With the 8.3:1 comp ratio it should take an extra 10deg or so almost everywhere, because it was setup for the timing of the 9.0:1 25det motor.

AUTOSPEED:

Massive turbo to run 345rwkw my asss, you could run a .67 rear housing and get near to that figure and the thing would fry the tyres at 3g..... These guys gave the response a good go but are just taking the easiest route to cover their arses. The nissan rwd box will be marginal at those levels but a tricked up standard auto wouldnt be!!!!

As for GTR stuff he didnt really ask that did??!!!!

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