Im running a 454, .6 lift cam, 781 heads, with a 750 holley carb in s. florida. im currently running 84 front and 94 rear, but im going to get richer jets.

I was wondering what ppl with similar set up were running?

I also have 3/8 fuel line running from the tank to the carb, what size did u go too 1/2 or7/16?

My engine sometimes starves for fuel around 4500 rpms so i figured i would make some changes.

Try checking your vacuum when running flat out you might need to jet down , have also had problems with using the power valve

For reference. I am running old Holley Barry Grant 750's. My 454's were dynoed at 590HP @ 6250RPM, 3/8" fuel line. My jetting is 76 primaries, 6.5 power valve. Secondaries are 82, blocked no power valve. I have O2's in my pipes and run ~12.8 AFR. My heads are about 330cc and flow 400CFM of air. One of my best purchases was a $100 Innovate LM1 AFR off of ebay.
My opinion is, you are just guessing without one.

appreciate it i will get one of those and go from there, i did a wide open plug chop and was a little concerned looking at plugs. seemed lean to me...

With 590 hp you must be running blowers,

Wideband tuning is the way to go.
I bet he is running AFR's or similar to get more HP. Bob tells me I could get 600HP out of my 489 with a set of AFR's and matching cam.

Innovate LM1 AFR off of ebay. got one too they are the best

You are correct Jeff I am NA. 590 was with my steel JimV Merlin Wedged heads. I am now running Valako's new aluminum marine head that Dart cast for him. They are about 330cc runners based off a Dart 345 with JimV's hand ported ports cast at Dart. And they flow 400cfm. I have not been to the dyno with these heads, I should now be over 600HP. I just tuned with the LM1 in the boat.

I have the Holley MPI kit with the wideband option. I can tell the PCM what my targets are and it adds or sub fuel according. I am running the GM 820 large ovals seems to be about 520 HP with a 489. RMbuilder tells me I could get 600+HP with AFR's and matching cam.

i have a540block dart with same heads you have a single plane dart intake 1000 holley 675lift solit roller cam 718 hp at 5800 at 34degree

Rookie what specs do you have for a cam? that is alot of rpm, i cant get mine to spin more than 5000 with 21 pitch prop on a 24 with a .6 lift bob m cam. 781 heads. Unless im loosing big power somewhere in my valve train..
Im running domed forged pistons from speed pro.... Any thought besides the tuner