Fuel system questions

[Aleinsteingenius]

Time for some more dumb questions.

I am building a MK V roadster with a way overpowered Godzilla engine. Not many have done this before (probably for good reason lol).
The engine is as follows:
Custom-built 675hp 7.3L Godzilla crate engine with Holley oil pan, high mount and InnoV ITB
Fully machined 7.3 L cast iron 6 bolt main block
Block painted with high-temp ceramic engine paint
Ford 7.3 L forged crankshaft
H-Beam connecting rods (Molnar or Eagle)
Forged Performance pistons (Mahle, Wiseco or Diamond)
Complete assembly balanced (internal)
Custom ground hydraulic roller camshaft (Muscle Car Chop)
Hydraulic roller lifters
Three-piece timing chain set
Timing degree lock-out kit
Oil pump (Holley)
Ford 7.3L cylinder heads
2.170 8mm intake valves
1.67 8mm exhaust valves
Beehive valve springs (Pac)
Valve retainers and locks
Ford rocker arms
Chrome moly pushrods
Head bolts
Alum timing cover (Holley)
Alum real seal housing
6.5-quart alum oil pan (Holley)
Valve covers
Coil covers
Harmonic balancer
InnoV8 intake manifold and throttle body
Holley fuel rail kit
Throttle position sensor
Idle air control valve
Fuel injectors
Holley Terminator X-Max ECU
Intake air temp sensor
Crankshaft position sensor
Camshaft position sensor
Wide band O2 sensor
Main ECM engine wiring harness
ECM power harness
Coil pack harness
Fuek injector harness
Misc harness extensions
Coil packs
Spark plugs
Plug wires
Oil and filter
Water pump (Holley)
Holley High-Mount Accessory Drive Kit - Alt, PS, AC

221350

I am trying to figure out the fuel system. I like Paul's (Edward B) way of doing it, putting the pump in the tank with the filter and regulator back by the tank with only one line going forward to the engine bay. I am thinking about using the Holley 525LPH pump (PN HLY-12-34&), the Summit Racing in-line 10 Micron filter, and the Aeromotive Universal Bypass regulator (PN AEI-131130). These all use 6AN fittings, and I would use 6AN Aeromotive PTFE stainless hose. I have had good luck with Aeromotive products on airplanes.

My engine is not here yet. I expect it this week or next. It is a very big motor going in a very small car, but "Anything worth doing is worth overdoing" lol. That is why I am leaning towards having the regulator in an accessible place in the back.

My question is this. What am I missing? The fuel pump should be plenty big and the amperage draw looks ok.

[PNWTim]

Going to be a beast for sure. As long as you are running an internal pump your fuel line will easily support your horsepower. You could move up to -8 but it's not needed. Your pump is more than sufficient for your application.

You may want to ensure you use large radius 90's on your AN fittings (if you have any) but other than that, it looks good to go.

[Mike.Bray]

Check the ID of the AN hose you're planning on using. Assuming it's Teflon lined, which it should be, even though it's a -6 it can be quite a bit smaller. They're not all the same, I have -6 hose that's less than .300" ID and others that are closer to the nominal 3/8. TBH, with that engine I would run -8 hose just to be safe.

For stacks I like the regulator near the engine. On my Borla setup it's a part of the fuel rails. Run your line up to the first fuel rail, out of it and into the second fuel rail, then out to the regulator so that it's in the return line which goes back to the tank. This keeps fuel circulating in the rails and insures constant pressure to the injectors which is important. Fuel control is by the ECU controlling the open time of the injectors in ms so if the pressure varies the amount of fuel injected will vary. Not good.

Hope this helps.

[Aleinsteingenius]

Tim the good people at Summit agree with you that the Holley 525LPH pump is the way to go. Mike, the engine builder, agrees with you that I should go with 8AN hose and that I should install a Y and feed both injector rails. I ordered a lot of stuff from Summit and Speedway Motors.

[Mike.Bray]

I should install a Y and feed both injector rails.

That's interesting. I've done a few stack systems but I've never done the fuel system like that. I've always fed the rails in series and put the regulator on the outlet in the return line.

If you feed the rails from a single line where are you doing the return line from?

[Aleinsteingenius]

It sounds like they want me to put a Y at the back end of the rails for the return line. I will post pictures when I figure it out.