RF Harness and fuel pump relay

[DesertSn8ke]

I'm going to be running a 340 LPH Aeromotive style in-tank fuel pump. The install directions for a proper install show using a 30 amp relay and 10 GA wire to power the pump. According to the flow curve in the directions it is pulling about 13 amps at 60 PSI. I see the RF harness has a 15 amp fuse on the fuel pump circuit, but I see no information on what the built in relay is rated for, nor wire sizes. Is anyone using the stock RF harness to power a 340 size pump or larger? What is the included relay rated at? Thanks!

[edwardb]

The largest I've run on the RF harness is a 255 LPH in-tank pump. Couple of times and no issues after multiple seasons and many miles. At some point, maybe need to trust that RF would use the proper wire size and relay for the 15 amp circuit. If your pump is really only pulling 13 amps (easy enough to measure) then the RF circuit should be OK. Pretty sure the wire size isn't 10 gauge though. Just from memory, I'd guess it's 12 gauge. 10 is pretty conservative for 13 amps. Automotive relays are typically good for 30 amps or so. Should be marked on the relay. Higher current ones are easily obtained, but a moot point if the circuit is fused at 15.

FWIW, you posted this under ask a FF tech. They don't actively monitor this and haven't seen an answer from them on here for a long time. You'll probably get more traffic (and responses) under whatever specific category you're asking about. Roadster, whatever.

[Papa]

I assume you will be running this pump with an EFI setup. What ECU are you using? It likely has its own fuse and relay included in the harness that comes with it.

[DesertSn8ke]

I should clarify a few things I suppose. I don't have the kit or harness in front of me yet. Delivery date is October. I ordered a base kit plus options, so I've been ordering parts to have on hand when it does get here, hence my question on the relay. All I have to look at is the install manuals, and all I could glean from that was the 15 amp fuse, but no info on the relay rating or wiring size.

Yes to EFI, specific system TBD, though I like the looks of the Edelbrock PF4. Good to know the ECU might have its own built in relay and/or circuit, I'll have to do some more digging. I'm also planning on using a Digital Guard Dawg PBS-1 key-less ignition, and it has built in 60 amp capable accessory relays, so that may be yet another route. Sounds like I need more pieces of the puzzle on hand before I decide how it all fits together.

Thanks for the input!
Thanks for the suggestion on where to post. Still new here. I thought about posting in the coupe forum, but didn't see any electrical specific sub-forum, though I don't suppose it matters.

[Chopper]

FWIW, I have a Pro-flo4 and think it's a great system. It's working flawlessly for me (306 SBF). That said, if you choose it, the PF4 can directly drive a fuel pump up to 10 amps. If you need more amps, you have to run a separate circuit and use the PF4 to control the relay. That circuit could be the RF harness if it fits your needs. This is also well documented in the Proflo4 manual if you go that way.