stock s197 4.6 fuel pump + 39# injectors

[js197]

Hello,

I have been reading through alot of other threads on the internet. there are many threads with similar questions and a few threads I found with this exact question but they are now broken links (or cant be opened on my pc due to network security).

maybe I am just reading the wrong threads but I cannot seem to get a solid 100% sure answer.


How much rwhp can be supported by a stock 2005 GT 4.6 3v pump fuel pump (not a 5.0 fuel pump) in a turbo setup?

From what I understand the 39# injectors should not have any problem keeping up, its the pump that I am not 100% sure on so I am trying to find some confirmation.

this will not be a SC setup. it will be a turbo setup (as you know a SC setup is robbing power so fueling for 450rwhp in a sc setup is actually demanding more fuel than 450rwp in a turbo setup)

no mods to the pump, no boost a pump. just a stock 05 GT fuel pump and stock wiring with 39# injectors.

If this has been answered somewhere else please feel free to delete this thread and send me a link.

I just need to know for sure if my stock pump can safely fuel up to 450rwhp without any other fuel system mods aside from the injectors.

I doubt I would ever be full throttle long enough to be making 450whp on the daily commute, but I need to know that the 0.0001% of the time that I do have some fun and the requirement for fuel flow comes up that the stock pump can support it.

I believe the more basic Roush SC kits with pulley upgrade are making similar power with just the injectors which makes me think I will be fine, especially without the drag of the SC increasing fuel requirements.


Thank you.

[OneQwkStang]

You will know when your dyno tuner tells you your maxing it out. Then have them back it down until its safe. Pretty sure you will need a boost a pump.

[Uncle Buck]

I'm pretty sure you'll be out of fuel before 450. For a couple of hundred buck you can add a Walbro to your existing pump chassis that's good to 500

At the very least do a wiring upgrade to improve efficiency of you pump.

Here's a decent article on s197 component limitations

http://www.hotrod.com/how-to/additio...-ford-mustang/

In the article, 400 is the max for stock pump if going FI

I plan to use these for my DOB build aimed at 450rwhp. Walbro 405 in a stock hat and the wiring upgrade from S&H

image.jpg

[ZR]

My suggestion, Shelby dual pump kit from Ford Racing. It's a very well put together complete plug and play kit that'll handle your current plans and then some while barely breaking a sweat. Not a fan of boost a pumps.

[js197]

ok been doing some reading up on the sct i have. Didnt realize it at first as i havent played around with it much but i think i can monitor and log fpdc and fp pressure on my sct. My car is in storage so i havent been able to boot it up but i believe this will give me indication of approximately how far i can go with what. That train of thought led to some better worded google searches and it seems in a post on another board a guy was hitting around 96% fpdc at 265whp on his supercharged setup.

I am still pretty new to the s197. The last car i had was a return style fuel system and i user a stand alone megasquirt tuner with a completely seperate harness which didnt have a fuel pressure sensor or any fpdc readings so just made sure the pump was overkill for my application and forgot about it.

In the summer i went by dasilva and was talking to him about the sct. He mentioned that i am able to purchase the sct tuning software. Sounds like that is the way to go if you like to fiddle.

I dont think i am going to be pushing near 450whp, but you never know. It could put down one number while its heat soaked on the dyno and i think im nowhere near the limit of the pump but then a cool run on the street with good air causes different fuel demands etc.

Difference on my last cars engine was 20+whp between a relativly cool engine+IC vs heatsoaked after several pulls.

From what i understand the 3v is very suseptable to heatsoak so im assuming things could vary as much or more compared to my previous 4 banger.

Really only looking to make around 400whp but ya never know. Theres quite a difference when tuning the car in june and then one day its a cold november morning, maybe you get a little bit of a boost spike on that first run of the day and the next thing ya know i could be maxing the pump.

Anyways. Thanks guys for all the input. I will start small and work it up as needed. Really hoping to avoid the bap or bigger pump but we will see how things go.

[ZR]

Even in a mild n/a application, things can go wrong in a hurry. Now take that same engine + boosted via power adder of your choice, by the time you realize there's a problem, in many cases the engine is already finished. Return / non return, basic principles of building the fuel system still apply, you were on solid ground with your previous build. Don't be taken off track by thinking it's "only" going to make X h/p , it's an extremely common misconception. Same with thinking it's only going to be at max h/p once every blue moon. Even in a build where large margins are properly addressed, things can go wrong, shrink the margins and the chances increase proportionately.
Just my .02

[ZR]

I'm pretty sure you'll be out of fuel before 450. For a couple of hundred buck you can add a Walbro to your existing pump chassis that's good to 500

At the very least do a wiring upgrade to improve efficiency of you pump.

Here's a decent article on s197 component limitations

http://www.hotrod.com/how-to/additio...-ford-mustang/

In the article, 400 is the max for stock pump if going FI

I plan to use these for my DOB build aimed at 450rwhp. Walbro 405 in a stock hat and the wiring upgrade from S&H

image.jpg

Nice to see a kit that address's the small factory wiring. No upside to installing a pump that requires more amps to properly run vs what the wiring can supply. How did that compare in cost to the FMS dual pump kit?

[NickD]

Join s197 forum there is a thread on this exact subject where they get far more in-depth and has a couple different suggestions

Sent from my HTC One_M8 using Tapatalk

[ZR]

What do they suggest Nick?

[OneQwkStang]

My suggestion, Shelby dual pump kit from Ford Racing. It's a very well put together complete plug and play kit that'll handle your current plans and then some while barely breaking a sweat. Not a fan of boost a pumps.

I run this well north of where you want to be, with no fueling issues. I'm the type that would rather have more than enough, and not run on the ragged edge.