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this is very interesting. what sort of bottom end improvement could this yield on an RB26?

http://www.skylinesaustralia.com/forums/Rb...html&st=200

Some bloke gives away a secret if you read page 11. It has obviously been done but how and also how to do it reliably.

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  • 2 years later...

This is interesting, any info on how to go about incorporating VCT into a 26?

Paul from Red R Racing has had something available for a while now having VCT on the RB26 head; simple and cost effective solution from what I have seen. One of his Stage 2 heads with VCT would be a total animal with the right turbo combination!

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  • 8 months later...

There was a more recent post on VCT for the RB26 head but I can't find it now. The link further back in this thread doesn't work. Does anyone have a chart showing the curve for an RB26 with VCT switched on and off to compare? It seems ERD and Red R Racing have developed a VCT system for the 26 - does anyone have prices for a completed head or for conversion of a supplied head? And is special ecu software required or will most aftermarket ecus such as Link/Vipec and Motec be able to run this OK?

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http://www.skylinesaustralia.com/forums/index.php?app=core&module=attach&section=attach&attach_rel_module=msg&attach_id=364854

That's the link to the dyno graph I PM'd someone here. The runs were done one after the other on 10psi boost on a bush bearing T04Z. We still hadn't done a larger inlet cam at this stage so the spec on the inlet side were roughly around the 245 deg advertised x 8.3mm lift. The car has a larger inlet cam in it now which has improved the response slightly but the wheels have changed since then too so I can't do a comparo from the baby cam to the new one

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The Green line is VCT off and Blue line is VCT on.

Also when the boost was increased to 30psi, the response gap between the two is larger. The VCT switching point should be just prior to the line intersection and it will follow the higher line but your tuner should know that already.

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The real world gains in advancing inlet camshaft timing at low to mid engine rpm far out ways the given gains in the displayed dyno graph but it does clearly shows the result of net losses if cam timing is left in the advanced position

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