I have a LM-1 meter with a wide band O2 sensor. I had adapters made that go between the manifold and riser for the sensors. AZM reprogrammed my ECU and said to run stock fuel pressure, it is 37 at idle and 40ish at wot.

I agree the fuel pressure seems to low at wot. Are you using an Aeromotive fuel pump with the ProCharger? My fuel pressure is in the 70's at wot.

Mine is around 30 at idle and close to 60 at WOT, I am using stock mercruiser pumps in mine. I have done plug checks at various RPMs and they look great.

With the re flashing of the ECU you don't have to jack up the fuel pressure to get the right mixture. The pulse is now longer to let in the right amount of fuel to compensate for the boost and added cubic inches. Before the re flash my fuel press was at 60. I don't use the boost sense line on my FMU now.

My guess is you're experiencing the limitations of the intake system and stock cam. Your boost is due to the high restriction, you're really not moving much more volume of air than you were. You do have a lot more torque at lower RPM, so go up in pitch and make use of it. That intake is very restrictive. You're probably leaving 100 HP on the table with that setup. Your speed is indicative of about 525 HP at WOT. Your engine should make near 600 with the correct intake and cam setup. Come see me and we can experiment

Another thought, what is your timing running at total advance? You may be needing some more timing. It would be nice to make a run with a computer with diacom installed and log the data to see what is really going on. Those aluminum heads may change your timing requirements some.

Is his mpi intake the cast iron one that resembles a cast iron 4bbl intake ?

BTW: by notes which I have Merc roller cam with spec's below. Unfortunately, I do not have listed if this is what they used for the MPI motors or just the 2bbl motors. If it is for MPI motors also, then, yes, there is a lot to be gained by swapping it out.

Stock hydr roller
.004" 258, 272
.006" 249, 264
.050" 197, 207
.430", .450
109 LSA

Only running about 28* of timing right now. I am a little gun shy of more due to the condition of the last motor. I'm sure I will start bumping it up as I get some more hours on it. I will probably do a cam change in the off season. What would you guys recommend?

Blowncrown,
Use caution when excessively retarding timing to control detonation. When timing is reduced your EGT's will increase dramatically per given boost/AFR/CR. The elevated exhaust valve temps may result in valve failure or creating the very detonation you are trying to avoid. It is very possible you will end up swapping one catastrophic root cause for another.
Bob

The intake is the Vortec truck intake with the TB on the front. It has runners that loop around for good low end torque. They use that same hydraulic roller cam in all versions of the 5.7.

RMBuilder...keep in mind he is using the Edelbrock ETEC heads which I believe are a fast burn design similar to the GM Vortec so they don't need a lot of timing. He would probably be OK with a couple more degrees of timing since the heads are aluminum. IMO.

Blowncrown, I still think you're a little lean on that A/F. I like to see around 11.5 under boost. Maybe you could bump the fuel pressure up a couple of pounds. It won't make any more power but may live a little longer.