Pro Flo 4 with Delphi FE0114 or ACDelco EP381

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TommyGuns

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How much hp is the motor making. That dictates the size of the fuel pump.
No idea. I didn't build the motor and I haven't had it on a dyno. Putting it on a dyno wasn't on my to-do list for the truck. Apart from the Vortec heads and a mild cam, the motor isn't built. It runs on regular gas without detonation, so the compression is close to factory. My guess would be around 280 HP.

I read it as one of these guys under the hood right now, and he is looking to go with an 87 tank and fuel pump setup.
If he has something like this now, he can pull the pump itself out and see if it is the right size to go in the 87 hanger. You would just have to make sure that the 87 pickup sock is in the right place to have a seamless setup.
Correct, the Edelbrock fuel sump. They come pre-set to 58 PSI, but it is adjustable.


A factory vortec era pump is perfectly fine for engines up to 400hp or so. What isn’t correct is the proflo 4 regulator you have. You should be running the 43psi regulator and corresponding base tune. The 58psi regulator / tune is for engines that make higher horsepower that most factory headed small blocks will make.
The only regulator I have is in the fuel sump. Edelbrock sells only one kit for a 350 with Vortec heads, and it includes 58 psi fuel injectors. From what I've read, the only difference with running 58 psi injectors on a base tune engine would be the injector cycle would be shorter than it would be with 43 psi injectors. The 58 psi injectors of course have a higher performance ceiling.
 

TommyGuns

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I'm certainly no expert, but as far as I know, the rail pressure needs to match what the injectors are designed to run at, for a good spray pattern. Volume is for HP capacity, pressure is for injector performance.

Many GM vehicles in the later 90's started running higher rail pressure (58 psi), even the fwd V6's making as little as 160 hp.
 

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For clarity, this is the kit that is installed on my truck:

It includes 29lb, 58 PSI injectors. I just noticed that according to their product page, this kit is rated for up to 450 hp, not 600 as noted in the manual.

I'd personally like to avoid buying a new set of lower pressure injectors. It looks like a set of 8 would go for around $600 or more.
I have the same kit. The injectors are rated in lb/hr. That’s not the variable you change, it’s the fuel pressure regulator. They come in either 43 or 58psi. My kit also came with the 58psi regulator. I bought the 43psi regulator separately because it was for a basic vortec 350 at the time.
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What you need to figure out is the actual hp output of your engine. Honestly, 450 hp takes some work from a factory vortec headed 350 with a mild cam. Not extraordinary or impossible, but you’d probably be over 10.5:1 comp running 91 octane or higher with cam specs that’d require machine work to the vortec heads or beehive springs, etc.

For reference, a factory vortec 350 was putting out 255hp. 200 more hp takes some doing. A Blue Print 383 with nice aluminum heads and a decent cam is barely making 450 hp.

Maybe Edelbrock changed their recommendations, but this is the table straight from their manual:
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EDIT: I see above where you guesstimated 280 hp. In that case I’d assume you’d want to run the 5006 or 5008 base tune with regulator set to 43psi. I stand corrected, they did not have the adjustable regulator when I did mine. Maybe they did, but it just wasn’t on my radar if it was only part of the sump kit. Back to the original question, yes a vortec era in tank pump is perfectly adequate. I had one running that way with no issues. Maybe @SquareRoot has time to chime in between LS swapping and axle spelling corrections to let us know what regulator and tune he is running. I think his engine setup is very similar to yours.
 
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Doppleganger

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I have the same kit. The injectors are rated in lb/hr. That’s not the variable you change, it’s the fuel pressure regulator. They come in either 43 or 58psi. My kit also came with the 58psi regulator. I bought the 43psi regulator separately because it was for a basic vortec 350 at the time.
You must be registered for see images attach


What you need to figure out is the actual hp output of your engine. Honestly, 450 hp takes some work from a factory vortec headed 350 with a mild cam. Not extraordinary or impossible, but you’d probably be over 10.5:1 comp running 91 octane or higher with cam specs that’d require machine work to the vortec heads or beehive springs, etc.

For reference, a factory vortec 350 was putting out 255hp. 200 more hp takes some doing. A Blue Print 383 with nice aluminum heads and a decent cam is barely making 450 hp.

Maybe Edelbrock changed their recommendations, but this is the table straight from their manual:
You must be registered for see images attach
Was this in the manual that came with the PF kit? I have the E-Tec heads - guy who built it said its easily 600hp. This should be fun to figure out.
 

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Was this in the manual that came with the PF kit? I have the E-Tec heads - guy who built it said its easily 600hp. This should be fun to figure out.
How many cubes? What are the specs? Maybe a proper dyno tune would be worth the investment. That’s one of the nice aspects of buying a complete setup from a company such as BluePrint. It comes dyno’d with a warranty, so you know exactly what you are getting.
 

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How many cubes? What are the specs? Maybe a proper dyno tune would be worth the investment. That’s one of the nice aspects of buying a complete setup from a company such as BluePrint. It comes dyno’d with a warranty, so you know exactly what you are getting.
Its a 350 - a 97 block with an Edel roller cam and heads. This guy has been building motors for 40yrs. I cant prove his 600 figure is accurate but I would venture to say its more than the 400 mark.

The head tech at Edelbrock told me the same numbers (600hp/500 ft lb) - said he owned 3 speed shops in SoCal and had built that engine so many times that was a number he "knew". But in hindsight, he was a jckarse that lied about everything he sold me, so who knows.

If its ever finished, it will get dyno'd for sure.
 

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Its a 350 - a 97 block with an Edel roller cam and heads. This guy has been building motors for 40yrs. I cant prove his 600 figure is accurate but I would venture to say its more than the 400 mark.

The head tech at Edelbrock told me the same numbers (600hp/500 ft lb) - said he owned 3 speed shops in SoCal and had built that engine so many times that was a number he "knew". But in hindsight, he was a jckarse that lied about everything he sold me, so who knows.

If it’s ever finished, it will get dyno'd for sure.
1.71hp/CI sounds like a rowdy azz engine. This is for a truck?! I’m a dummy when it comes to this sort of stuff, but I’d imagine the meat of a 600hp 350CI small block is going to be above 4000rpms.

Not to mention I’d assume a very high CR needing to run on Ethanol blends.
 

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5-600 on a heads and cam 350 cant be right.

Im not saying impossible, im saying theres few and far between without making compression stupid tall
 

TommyGuns

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I'm certainly no expert, but as far as I know, the rail pressure needs to match what the injectors are designed to run at, for a good spray pattern. Volume is for HP capacity, pressure is for injector performance.

Many GM vehicles in the later 90's started running higher rail pressure (58 psi), even the fwd V6's making as little as 160 hp.
Right, and the fuel sump I'm using has a built in vacuum adjusted fuel pressure regulator. Part of the installation instructions are to run the sump without vacuum and ensure it's set to 58psi. Then you connect the vacuum line to one of the ports on the intake, and at idle you'll see lower pressure, somewhere around 45 to 48 psi if I recall correctly.

EDIT: I see above where you guesstimated 280 hp. In that case I’d assume you’d want to run the 5006 or 5008 base tune with regulator set to 43psi. I stand corrected, they did not have the adjustable regulator when I did mine. Maybe they did, but it just wasn’t on my radar if it was only part of the sump kit. Back to the original question, yes a vortec era in tank pump is perfectly adequate. I had one running that way with no issues. Maybe @SquareRoot has time to chime in between LS swapping and axle spelling corrections to let us know what regulator and tune he is running. I think his engine setup is very similar to yours.
It seems that even though the Pro Flo 4 is newer than the Pro Flo 3, 2, etc.. there have been a few versions of the Pro Flo 4 kit. For instance, mine didn't come with the Android tablet to connect to the ECU. Earlier kits did. The pressure regulator you linked was not included in my kit, but it is something I'll need to add when I eliminate the sump, I just haven't purchased it yet. I have a 58 psi regulator saved in a cart. But, I read on the Edelbrock forums that lower pressure injectors on a lower performance engine can make it easier for the ECU to manage the AFR. I'm undecided if I want to drop another $600 to replace the injectors with lower pressure parts. If I could somehow sell them and recup some cost that might make it an easier decision, but I doubt there's a market for used fuel injectors.

I have seen @SquareRoot's posts and I was hoping he'd give his input. I saw a recent comment from him on another thread where he showed the Delphi fuel senders and pumps he was installing in a second EFI Squarebody.
 

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Right, and the fuel sump I'm using has a built in vacuum adjusted fuel pressure regulator. Part of the installation instructions are to run the sump without vacuum and ensure it's set to 58psi. Then you connect the vacuum line to one of the ports on the intake, and at idle you'll see lower pressure, somewhere around 45 to 48 psi if I recall correctly.


It seems that even though the Pro Flo 4 is newer than the Pro Flo 3, 2, etc.. there have been a few versions of the Pro Flo 4 kit. For instance, mine didn't come with the Android tablet to connect to the ECU. Earlier kits did. The pressure regulator you linked was not included in my kit, but it is something I'll need to add when I eliminate the sump, I just haven't purchased it yet. I have a 58 psi regulator saved in a cart. But, I read on the Edelbrock forums that lower pressure injectors on a lower performance engine can make it easier for the ECU to manage the AFR. I'm undecided if I want to drop another $600 to replace the injectors with lower pressure parts. If I could somehow sell them and recup some cost that might make it an easier decision, but I doubt there's a market for used fuel injectors.

I have seen @SquareRoot's posts and I was hoping he'd give his input. I saw a recent comment from him on another thread where he showed the Delphi fuel senders and pumps he was installing in a second EFI Squarebody.
I’d call tech support. The 29lbs/hr injectors are already just about the lowest flow eddy injectors you can get. I would stick with the 29lbs/hr injectors and run the 43psi regulator based on Edelbrock’s chart above.

Again, that’s the exact setup I ran with a PF4 on a 300ish horsepower vortec SBC. I called Eddy’s tech support line to ask if I could get away with the 58psi regulator and they said it wouldn’t be ideal unless it was approaching 450hp.
 

TommyGuns

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I’d call tech support. The 29lbs/hr injectors are already just about the lowest flow eddy injectors you can get. I would stick with the 29lbs/hr injectors and run the 43psi regulator based on Edelbrock’s chart above.

Again, that’s the exact setup I ran with a PF4 on a 300ish horsepower vortec SBC. I called Eddy’s tech support line to ask if I could get away with the 58psi regulator and they said it wouldn’t be ideal unless it was approaching 450hp.
Perhaps I'm confused. The injectors I have are 29 lb/hr, 58 PSI injectors. If I want to run 29 lb/hr at 43 PSI, wouldn't I need to change to injectors rated for 29 lb/hr at 43 PSI?

I'll give the tech line a call for sure once they open again.
 

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I'm running a Vortec 350 with a decent cam, about 360hp. I have 30lb/hr injectors at 43psi, running a Walbro pump (255 l/hr which is 67gal/hr). Not a Pro Flow 4 but a similar style setup. For me it is plenty, for you it is definitely adequate.
 
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