EFIDynoTuning Forum

alright then, i think i have enough information to proceed... if all goes well, i should be getting in touch about dialing in a base tune in the coming months.

thank you so very much for the info and advice.

okay, that is a very useful piece of information... I wasn't making a distinction between returnless and mechanical returnless.

if the Holley sender claims to send 58psi with the built-in regulator in the tank, i guess that makes it mechanical returnless. does that obviate the need for a PPRV?

i see that you recommend always running at 65psi base pressure for the kind of injectors i'll be using... is trying to run 58 psi on an A9L a matter of changing a scalar value, or would I be starting my tuning journey by walking through the gates of hell?

on a related note, are you still doing remote tunes?

Thanks, I didn't realize you had a section on this one the pre-tune page.

@ATPCR It's not about value or originality. This car was a 6cyl automatic that I bought as a 347 & T5 with a 4-point cage. Unfortunately the 347 was a '72 block which was tired, fuel-washed, and built with undersized pistons (?).

I have had this 5.0 setup on the stand for a few years, so I figured it was a good time to give it a home.

I was trying to figure out whether returnless will even work with an A9L, and which setup is better for my use case. All the information I keep finding is conflicting.

decipha wrote: ↑2024 Apr 03, 14:47 what all are your fueling needs? what all are you doing to this engine and plan for down the road?

if its just a stocker for now a simple 190lph pump would more than suffice.

best bet is to keep the canister purge but its not necessary, its nice though

thermactor doesn't matter as its not important

I should have included that info.

The goal is 80% street and 20% strip with close to 1989 emissions standards so my wife will actually ride in the car with me. I'd like to cruise on the highway, spin the tires a little at green lights, and go to the track once a year. It'll have to tolerate stop and go traffic in July because I live in a large city.

I have a full 1989 A9L wiring harness and vacuum system that I have isolated and run on a test stand with a stock 5.0.

Since I haven’t run the complete setup in a car, the most important milestone is to get as close to a factory '89 setup as possible. I’m hoping I can put the QH on and start to drive and tune without chasing my tail from introducing a million variables at the start. Then I can start thinking about new intakes, injectors, throttle bodies, etc.

I have a friend building that 1991 E7 into a 306 with SVO heads, Keith Black pistons, and probably an XE274HR cam. I'm replacing the T5 with a TR3550.

We're aiming for somewhere between 9.5:1 to 10:1 with 350-400hp NA at the crank. He's building in some leeway for boost in the future, but who knows if that will ever happen.

I think I have almost all the details of the swap figured out, except the fuelling.

Right now it's got a Holley Red putting 7psi through 20+ year old 3/8" braided stainless lines. Last year before I knew I'd be doing any of this, I put in a new Spectra tank and sender, and had the tank coated.

While trying to think of ways I could keep the tank, I considered going returnless (and I have to respectfully disagree, I think some ’99-’01 5.0 explorers had returnless fuel systems https://www.ebay.com/itm/256230059146?chn=ps) But then you started using words I don’t understand like PPRV, other people said it wasn’t a good idea with an A9L, and I lost my nerve. Again — too many variables.

Here’s what I think my choices come down to:

• 255lph inline pump with an aftermarket return-style sender. downside: there is no ventilation on this tank except the gas cap, and I can’t weld on a fuel tank. which means CANP is basically out.

• Shell out for the Tanks, Inc. setup, run bulkhead AN fittings through the trunk floor, integrated vent for CANP, try to sell current tank locally https://www.speedwaymotors.com/Tanks-MU ... d_source=1

I don't think either are terrible options, but I also have a habit of overcomplicating things. I know you've seen it all, so I'm interested in your opinion.

ATPCR wrote: ↑2024 Apr 03, 09:01 barless66, Here is a complete tank/fuel pump kit for the '65 and '66 Mustang for about $100- more from Speedway. It has multiple lines so I suppose that you could "cap" any extra ports not being used.
https://www.speedwaymotors.com/Tanks-MU ... gKK4PD_BwE

Thank you ATPCR, I've had my eye on this setup. It looks solid and affordable. My only hesitations are needing to pass two lines through the trunk floor, and the fact that I literally just installed a professionally coated Spectra tank last summer... *facepalm*

decipha wrote: ↑2024 Apr 02, 16:45 Wow, I used to buy the cheap $30 ebay china made oem replacement hats, drill out a hole and put an AN fitting on it. /done

Only the 1999 to 2010 were returnless.

2011 the mustang went back to return style or as they call is 'mechanical' returnless which means the regulator is just mounted in the tank.

Nope the 1999 explorer does not have a fuel rail pressure sensor since it is a return setup as well but again henry just simply put the regulator in the tank. You could do the same if you want to just run one line up front. All you need is a PPRV for any 99+ mustang but you'll have to modify that line to fit it regardless.

First of all, thank you for the response... big fan. I bought one of the last Moates QH for sale thanks to efidynotuning.com, and I will be trying my first ECU tune on this A9L this summer.

So I realize the Holley unit isn't exactly a bargain (and I missed the sale price), but it does have the pump built-in and I can use my existing tank.

The other appealing thing about the Holley pump is the Hydramat, because my stock tank doesn't have baffles and I'm concerned about fuel starvation, which I want to avoid at all costs. I was hoping to reuse my current tank because it's a new Spectra that I had professionally coated last year, before I knew I was doing this swap.

Another good option is the complete tank/pump/sender setup from Tanks Inc linked by ATPCR https://www.speedwaymotors.com/Tanks-MU ... d_source=1 which is practically the same price, and looks like a solid setup.

While I've got you... I'm trying to keep this swap as OEM as possible, to reduce variables for my first tuning experience. One of the things I like about the Tanks Inc (hat? am I using that right?) is the vent tube, because I'm hoping to keep the CANP in my swap... but is that stupid? Keeping it with my current tank would mean drilling/welding a vent, which I really don't want to do. I'd be more likely to leave the canister out if I keep the Spectra tank.

I'm also probably going to leave out the Thermactor, because I may run hi-flow cats in the future, but they won't have that pipe connection between them.

Anyway, back to fuel: what would you do in my situation? I'm more concerned with doing it 'right' than doing it cheap, but I also don't want to blow money unnecessarily. I'm being pulled in many directions and I'm not sure which way to go.

Thanks for your time, I appreciate it.

I’m in the process of putting an ’89 Fox powertrain into a ’66, and I’m currently thinking about fuelling.

I have the chance to buy this Holley in-tank EFI fuel pump for a really good price:

https://www.holley.com/products/fuel_sy ... rts/12-305

it looks perfect for my usage, except that it’s a 3/8 inch returnless line. i have the option of running a returnless fuel rail from a ’99 5.0 Explorer, or custom AN returnless rails. and it would be nice to only need 1 fuel line.

I’m wondering if there could be some unexpected effects to the stock 89 setup if i go returnless. in terms of fuel pressure regulation, injector pulses, confusing the ECU... whatever else I can't think of.

one key difference is the Explorers have their regulator next to the pump in the tank, and an ECU fuel pressure sensor at the rail.

let me know if you have any info to share about this. thx