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Hey Guys,

After another enjoyable day at WTAC, and hearing the gibson motorsport cars, can anyone explain to me why the HR31 sounds absolutly mental?

Is it all in the exhaust? (or lack of)

Looking in the bay obviously it has the GTS-R exhaust mani, but still has an internally gated turbo.

The note is different to pretty much any RB i've ever heard.

Could it be its maybe revving harder?

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Yeah someone on the R31 Skyline club had a replica made. Can't remember who. Pretty much just get someone to make the longest equal length runners that will fit in the engine bay.

Yes the car is a GTS-R but the manifolds were made by Gibson (slightly different to GTS-R, sound is pretty much the same I believe). If you were to throw a GTS-R manifold on your RB, it would sound pretty much the same.

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Why does it have a circular opening in the flange to the turbo ? Seems odd?

Also, the fact that the GTS-R and Gibson manifolds are tube not pipe, means the resonance from them will be different. If you want MAX banshee than tubular manifold will be the pick. not one out of pipe bends

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Didn't the GRP A regs state that the exhaust manifold had to remain standard from the head to the first join? Hence the VL Walky had individual exhaust runners about 3-4"long from the head, after which the exhaust was free.

If that's the case, how would Gibson have homologated this manifold? Or did turbo engines have a different set of rules?

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Didn't the GRP A regs state that the exhaust manifold had to remain standard from the head to the first join? Hence the VL Walky had individual exhaust runners about 3-4"long from the head, after which the exhaust was free.

If that's the case, how would Gibson have homologated this manifold? Or did turbo engines have a different set of rules?

They put the one they made in a Nissan box and showed the scrutineers. Not like any one knew what the cars had back in Japan anyway.

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  • 3 weeks later...
  • 2 weeks later...

And make a 4 inch side pipe as well.

Was amazing watching Skaife race one eariler in the year at PI Historics.

Coming out of the final turn and flat shifting down the straight... eargasm!

Sure was a great day.

You can't compare the Gibson to any other manifold, it is made from a special material with sand bent one piece runners. I can try and get some manifold pics next year at PI if you like, all the Gibson cars are together in the pits.

post-63525-0-36808500-1384730407_thumb.jpg

post-63525-0-45866700-1384730560_thumb.jpg

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