I'm not opposed to that idea. Would love it if someone could post some part numbers so I don't waste money on the wrong stuff.

check out the 496 cool fuel bypass thread

Just saw that. Thanks, will keep that in mind if no other explanation arises after Diacom runs.

some one else on here had low fuel psi or loss of power and it ended up being the fuel lines from the tank pickup to the fuel separator, the lines were collapsing internally,

Replaced pickups and lines from pickups to separators last week, no improvement. Also took out 90 degree fittings.

Only thing I haven't done is lines from separators to fuel pumps.

I have a couple used fuel pumps if you want to try them, changing them is a PITA one of mercury's better idea........

Thanks. Will keep that in mind. Stbd Pump replaced with aftermarket already, and new OEM regulator, still behaves exactly like Port. PITA for sure - did not enjoy the experience!

I must of missed a bunch of this.......... always late to the party

Did a Diacom run this morning. Connected to Stbd motor. Learned that my AutoMeter tach is off by a couple hundred RPM. Presuimably both tachs are off by a similar margin.
The ECM is showing me just barely tickling 4800 rpm whereas the tach is just barely indicating 4500-4600.

Diacom recorded no knock retard.
Ignition advance is 36-39 degrees at wide open.
Throttle position is indicating 99% when wide open, despite only reaching 81% with Key On/Engine off. Voltage difference of 5V reference when running?
MAP sensor at 4.92V at WOT / max rpm
Injector pulsewidth 8.5ms at WOT/max rpm.

So, I'm led to believe at this point that I'm over propped by a bit based on current HP levels, but perhaps someone more knowledgeable could look at the datalog and see if there's anything indicative of a reason for being down on power?

stock tune? quite alot of timing, even for a hot tune!