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Performance valve springs,collets etc(Bar-tek?)


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I was making just shy of 400hp from 11psi with a GT3582R, 0.82 AR.

With a standard engine, you usually see 400hp from 15-18psi.

But it's more than just the numbers. The whole rev range feels fatter and more responsive.

IIRC, my valves were reduced from the standard 7mm diamter to 4 or 5mm in the combustion area. In other words, the valves were still 7mm in the guides, but the exposed bit of stem when the valve is fully open was reduced.

In isolation that mod probably makes minimal difference, but when you add it to the other changes (cams, bigger valves, enlarged intake ports, 3 angle etc) it all adds up.

A standard 12V head can only flow a theoretical 280hp, normally aspirated.

Compared to a standard R32 head which can flow over 400hp normally aspirated!

So anything that gets more air into and out of a 12V head is very beneficial with boost!

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I like the idea of the valve stem reduction in the combustion chamber but i think im too much of a girl to do it.Id be frightened to death of one bending due loss of strength.Plus i like the cooling aspect of having sodium filled valves so if i was to machine mine down a bunch of crap would fall out of them lol.

Interesting about the difference in flow rates on the 2 heads though.Did you take much material out of your inlet ports or did you just gasket match the flange side and chamfer it down?

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Haha looks good. I'm running a t04B with a schimmel intake. So not as high revving as above.

I know an American with 290degree cams. Monsters.

290deg!Good grief.I bet he super triple checked his valve/piston clearance before starting that beast up for the 1st time ha ha.

The Schimmel intakes look real nice.It would hurt me a little to pay that uch for an intake when i can make one though so im going to be having a good look over Daverse's one tomorrow when we have a tinker with his new engine lol

I was going to go for 263 cams as im a little concerned with driveabilty as in summer it will be a daily/show car and ive heard 268's idle rough and arnt good around town?

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I like the idea of the valve stem reduction in the combustion chamber but i think im too much of a girl to do it.Id be frightened to death of one bending due loss of strength.Plus i like the cooling aspect of having sodium filled valves so if i was to machine mine down a bunch of crap would fall out of them lol.

Mine were diameter reduced by Ferrea themselves. No way I'd do that sort of specialist machining myself! Sodium filled are OK' date=' but inconel is even better for turbo engines ;) It's what the turbine wheel is made of in GTR turbos :)

Interesting about the difference in flow rates on the 2 heads though.Did you take much material out of your inlet ports or did you just gasket match the flange side and chamfer it down?

Schimmel built my head mate. For the price he charged me, inc shipping and import duties, it would have been uneconomical to build it in the UK :) But yeah, just a gasket match and chamfer job! He did a really nice job of it. Beautifully machined and resurfaced.

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290deg!Good grief.I bet he super triple checked his valve/piston clearance before starting that beast up for the 1st time ha ha.

The Schimmel intakes look real nice.It would hurt me a little to pay that uch for an intake when i can make one though so im going to be having a good look over Daverse's one tomorrow when we have a tinker with his new engine lol

I was going to go for 263 cams as im a little concerned with driveabilty as in summer it will be a daily/show car and ive heard 268's idle rough and arnt good around town?

From what I've read, the idle and low rpm manners are terrible with the 290 cams. But they built it to do 200mph, not cruising around LA :)

I find the VR6 idles better than stock with the 263s. Not rough or lumpy at all mate.

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Fantastic!Well i didnt want to go for the 268's but i didnt want to go any smaller than 263's so you have made my mind up thanks.

Im strugging to find a set of inconel valves but i will keep searching.

Im guessing fitting aftermarket cams on the vr's are completely the same as any other car and i wont have to get the cam housing/caps line bored?

I was looking at your old block on wednesday.That piston looks like its had some serious det! :-d

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