I realize that. It's been tuned to run with the current list of mods but I simply wondered if it could be tee tuned to work ok on the new long block to get me on the water a few times until the Holley stuff showed up. I'm a believer of doing things right so ide like to build it bigger and better now that it's apart. For a stock 502 with upgraded exhaust, fuel system and the M3 it ran decently well. I figured maybe I can send the mefi1 back to Arizona speed and maybe and have them adjust for the new heads, cam and whatever else the best they can and we run it. Swap to Holley latter. This is worst case.. What I really want is a solid aluminum headed 540 ish with a bigger cam, solid valve train Holley EFI in a multi port configuration with a stand alone throttle body that's easy to plum the charger to. I'm a Ford guy tho so I need help with ideas and a parts list here to build this motor. Thank you all four your help.

I'll help you build your 502,540,565,572 or what ever if you fix the turbo on my 6.0 :santa:

I can take you for a ride in my 700 HP/1300 ft pound of TQ @the wheels 6.4 Powerstroke. If that doesn't convince you to upgrade, we go see my buddy Rick. He builds Powerstroke all day long, we can fix you up lol.

I can tell you what was done to my 502. Bored to 509, 10.0 to 1 compression. Edelbrock marine heads. 315 intake runners. 1.89 exh valve. 2.25 intake. Crower cam part number E-44802. Modified intake runners flush with plenium. KN air filter,adj fuel pressure regulator. MSD 6m2. Imco power flow exhaust with 8 1/2 eddie marine slip in mufflers. Has Arizona Speed ecm. 14 quart oil pan. I have it in a 21ft Superboat. The boat is a beast,acceleration is amazing. Hope this helps

My 2005 6.0 with only 50K mls on it decided to go into limp dick home mode when I was pulling my TG back from Buffalo, turn the key off and on and the code goes away till the next long hill, 13K of boat and trailer with no turbo, its not good.

What code is it pulling? All stock?

little yellow openend wrench on the dash, book says, and I quote ( limp home mode ) I haven't got the exact code,............... back to your builds, contact these guys before you buy any parts, talk to Chris or Morgan................ http://www.cnc-motorsports.com/?gcli...FUNgMgodi3AAFg, their in your home state

I would suggest taking a look at this thread. "EFI for everyone". Some good info relating to your situation.

I was going to suggest cnc-motorsports to Fordtrucks also. They have good prices for what they sell, and they sell what they know works. What kind of budget are we looking at here? Ateco has a 540 shortblock blower motor listed in the classified section for $5395, and that would be with a new better block. I'm not sure if that MEFI 1 is going to be a good idea even for temporary, but maybe for break-in time if it can be setup to even run. By the time you mess with injectors, modify the intake/fuel rail and reprogram ecu or install a MEFI 3-4, you have paid for most of the Holley EFI system.
I would recommend either doing it all, or nothing. Better bet would be to get some parts from the swap shop and put the 502 back together and build a 540 for the ultimate goal. I mean with a 540, aluminum heads, good cam, M3 Procharger at 7-8 psi, you are looking at probably 900hp, so you need good parts to make it live.

Thanks for the thoughts Rocky.
I picked up another stock 502 rotating assembly for cheap out of the swap shop just to have. Still haven't decided if I'll go that route or the 540 just use. I have decided for sure on doing the Holley EFI, aluminum heads, dry exhaust and bigger cam. My question now is what size heads should I be looking at? There's different size intake runners... What are the power differences vers cost? I know everyone likes the dart pro 1s but there not cheap! Can I get a decently close head for a bit less? I want to stick with rectangle port like my stock heads are. I'm going to re use my Dana marine exhaust and just convert the tips to dry. Also, I might use my stock mpi intake and TB to get up and running, then switch to a better set up later. Not sure. No matter which rotating assembly I go with, I'll need over size pistons so those can be picked to match whatever heads we go with. Also, this is a blower motor so keep that in mind. Thanks!