Pumping Losses question
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Teching In
Joined: Feb 2008
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Pumping Losses question Hi, I have a 402ci LQ9 with a TVS2300 making 14psi boost. Compression ratio is 9.5:1 and it's making 617hp at the wheels (about 750 at the crank).
The blower is overdriven but with a smaller 2.7" pulley will make 17psi. Trouble is I'm told timing cannot be advanced past 4 degrees to take advantage of this.
My tuner says 14psi allows more timing and makes the best power. I have suggested adding water/meth injection and he says it will not make any difference at 17psi. He thinks the problem is due to a restriction on the exhaust side and what I'm experiencing is pumping losses.
My heads are Trickflow 225s.
Does this sound plausible?
The blower is overdriven but with a smaller 2.7" pulley will make 17psi. Trouble is I'm told timing cannot be advanced past 4 degrees to take advantage of this.
My tuner says 14psi allows more timing and makes the best power. I have suggested adding water/meth injection and he says it will not make any difference at 17psi. He thinks the problem is due to a restriction on the exhaust side and what I'm experiencing is pumping losses.
My heads are Trickflow 225s.
Does this sound plausible?
