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I have been thinking about this a fair bit recently, and wondered what people knew.

HKS VCam, is a wonderful bit of kit, but appears to be about £3k so very poor value IMO.

Is there a VVT system that could be transferred onto the RB26? I know usually these are not used on engines that rev much past 7500rpm. The RB25 Neo uses it, anyone ever seen one of these rev'd hard with VVT in place?

Anyone know which part is weak on stock vvt?

Just thinking out loud....:wavey:
 

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I think this had been done to death (try seach on vcam)

basic answer is

yes its very good

Yes its expensive (think the pro version is nearer £4K)

and no you cant use antything else ......................and if anyone knows better feel free to pm me
 

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I have looked into this at great depth.
The Nissan VVT has 2 cam positions, the HKS is variable.
Yes, if you have enough time you can modify your camshaft to have oil feeds to activate the pulley on the end.
Sensors are not really an issue but driving the setup must be a bit of a faf on the outset.
Delph worked with GM to design an electonic VVT pulley, oil free. Though would be bloody great as you can now have VVT on both cams.
However, I don't know what came of it..
 

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The HKS cam wheel is off a Subaru (with modification).
When you look at what's involved with the oil feeds, solenoid, VR sensor etc, the Vcam set up doesn't look so bad for the money.
 

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I personally think the vcam is a bit of a gimic, there's alot better ways to spend 3k on a rb26 cylinder head.

The lift on the cam is no where near enough to make that special in my opinion, ok hks done a few comparison videos but what can was it tested against? I bet it wasn't tested against a right nice custom 12mm cam specially designed for the spec of the engine.

Save yourself 3k and have your head sent to one of the top head specialist and spend 3k with them.
 

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I agree with Dan on this. Spending money getting the head work done properly and matching and spec up a good cam setup will yield very good gains and you can dial in the response your after. 4k is a lot of money and better spent elsewhere in the engine build.
 

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A cheap way to get exhaust vvt would be to just use an entire neo head, it would bolt straight on and there are a range of cams available for it.

But it would also mean you would be forced to use neo manifolds.

Although I could never find any facts I also read the stock neo head flow is better than a stock rb26.

It's not fully variable, but I don't think the majority of tuners have the time in a typical 1-2 day mapping session to get the best out of a fully variable setup anyway.
 

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A cheap way to get exhaust vvt would be to just use an entire neo head, it would bolt straight on and there are a range of cams available for it.

But it would also mean you would be forced to use neo manifolds.

Although I could never find any facts I also read the stock neo head flow is better than a stock rb26.

It's not fully variable, but I don't think the majority of tuners have the time in a typical 1-2 day mapping session to get the best out of a fully variable setup anyway.

Doesn't the rb25 have smaller valves? Your wrong about the flow of rb25 heads btw
 

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I personally think the vcam is a bit of a gimic, there's alot better ways to spend 3k on a rb26 cylinder head.

The lift on the cam is no where near enough to make that special in my opinion, ok hks done a few comparison videos but what can was it tested against? I bet it wasn't tested against a right nice custom 12mm cam specially designed for the spec of the engine
Variable can timing is the only way to get the best from your engine. Fixed can timing will always be a compromise.
What do you mean when you say 'a specially designed can fit the spec of the engine'?
 

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Yes, the RB25 Neo head flow is better than a stock RB26 head.

Have you flow tested one then Andy?

I mean a custom cam made specifically for the spec of the engine not just a off the shelf cam?

Yes I understand it's a compromise with a fixed cam but if the vcam had 11.5mm lift it would be a diffrent story but it hasn't the pro kit what's just under 4k is only 10.2 mm. It's all about flow and 10.2 isn't big enough the gains from 10.2 to say 12mm would be huge and I'd imagine the gains from the extra lift would out perform the vcam.

Without actual back to back test its all guess work but I'd bet people would be surprised.
 

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As cam lift increases, radians of free movement reduces.
Thus HKS, as much as I knock some of their products, have found a happy median.
Find a modern engine without VVT. The RB26 is prehistoric in that field.
 

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Variable cam is defiantly not a gimmick.
Next to no modern engine has fixed cam these days....that alone without the results is enough to prove it.
.....if the HKS setup wasn't drug money, it would be on my motor :)
 

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Some people say its adds similar gains as displacement, to which i saw was true i had a dyno graph with it off and on. i dont see a 10.2mm being all that restrictive as the it has a bigger variable

I think what should be said is... If you dont have headwork dont already, save the money for that :) some of us have ran outta things to do lol
 

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Variable cam is defiantly not a gimmick.
Next to no modern engine has fixed cam these days....that alone without the results is enough to prove it.
.....if the HKS setup wasn't drug money, it would be on my motor :)

It becomes a point were 10mm lift isn't enough, if it had more lift and wasn't a rip off price of consider the pro kit but the price is a joke and only being available with fcon is another joke
 

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Some people say its adds similar gains as displacement, to which i saw was true i had a dyno graph with it off and on. i dont see a 10.2mm being all that restrictive as the it has a bigger variable

I think what should be said is... If you dont have headwork dont already, save the money for that :) some of us have ran outta things to do lol
You was comparing to the same cam what wasn't variable. I would be very surprised if you will make 1000bhp on a 10mm lift cam

You got the dyno printouts to show us?
 
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