'66 Slant Six Turbo Build

moper said
First - I'm not a big boost guy....lol. But in regard to this passage:
"I've always know flow in lb/min and pressure as two different things which are related.
PSI is measuring density and flow lb/min is how much air is moving through the system and how quickly. Flow lb/min is ultimately what determines your peak power."

I'm not sure it I agree. As I understand it "flow" is the output of the turbine. It's dependant on the rpm of the shaft (the exh side) and the compressor side size and design. PSI is the measurement of the resistance of the intake tract to that flow. A great port will indicate less PSI than a bad port with the same compressor being spun at the same speed. It seems to me that the port is way restrictive (which fits every '6 peice I've read...lol) and you're blowing a lot through it. That may be messing with the signals the carb's getting and giving you the lean condition too.
I'm still in a learning curve for these engines but I'd definately look to make the ports work better. It will help with any turbo upgrade later.

Great head porting will make the whole system more efficient, it will allow more flow, create more power. As far as I understand the only thing that will significantly increase the PSI at the compressor is more exhaust flow spinning the hot side. Thus, more lift, bigger exhaust, better ports will only increase pressure because it will allow more flow, consume more fuel and create more - faster moving, exhaust.

If you think about it like a fluid system, peak pressure will not increase until energy is being applied to the system. If you load up a pipe with 20psi of water pressure it will not continue to rise unless more pressure is applied via a pump or piston or whatever.

In my case, the boost is rising because more exhaust flow is being applied than the turbo's little waste gate can bleed off. The waste gate controls the amount of exhaust gas/energy diverted from the turbine wheel, slowing the wheel down, keeping pressure under control.

Does that make any sense?