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Old 23-01-2010, 23:06
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CNHSS1 CNHSS1 is offline
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sorry, i want to flog the cam and head complete really, but Gripo on here has a brand new Piper cam for sale cheap.
power delivery has always been more importnat to me than max numbers, the way it comes on boost and the shape of the curve makes as much difference to the times as the actual bhp. In the end 15psi came from the most i could get at last dyno session on the external wastegate spring and boostsolenoid. Always planned to run more boost, but have decided to rebuild the car from the ground up following a pretty hefty shunt and go in a different direction on the engine (current class means i can run any engine). Had planned to run approx 21-23psi which i reckon would have seen around 315bhp.

Cams make a lot of difference to power delivery, as does the inlet manifold. Std cam strangles breathing over 5k rpm, and allow you can make the same figures as with a hotter cam, you have to shove loads more boost doen its neck which does nothing for the EGTs or reliability.
Inlet manifold again strangles things. The fwd facing type are much larger volume and allow shorter and neater intercooler pipe runs. I saw about 15bhp and 25lb/ft of torque when i added my current manifold. See pics in project section and for sale section.

the blocks were all machined by a friend who has a precision engineering firm. I gave him a DET block to use as a basis. Gotta be careful as you have to machine thru into the main oil gallery and close to other critical areas. I paid about £100 per block, but that was 5 years ago.
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