New EFI System

[Mike.Bray]

As most of you know I'm a HUGE fan of EFI and was an early adopter more than 30 years ago. I'm also a fan of the Edlebrock ProFlo4 system as it just works and works well. After over three years of development Edlebrock is ready to release their throttle body system which uses the same ECU as the ProFlo. For those that want the look of an old carburetor but the performance and drivability of EFI here you go.

https://edelbrock-files-v1.s3-us-wes...Street-EFI.pdf

[narly1]

Another plus of the PF4 set up is that the electronics are not buried inside the throttle body like some of the competitor's offerings.

IMO the underhood environment is not the best place for the electronics. Having a module tucked up underneath the dash makes a lot more sense.

Earl

[gbranham]

Love my ProFlo4, and I have Mike to thank for steering me to it, away from Sniper 2. I think ProFlo4 with true fuel rails and injectors is a better system than the TBI EZ Street EFI system, but I get it for those who just absolutely hate seeing fuel rails (even though they disappear under the air filter, for the most part). Still a better setup than Sniper 2. I wish more folks were aware there's better options than the Sniper, for basically the same money.

Greg

[CraigS]

While I tend to agree w/narly1, it is funny though how much of the electronics is under the hood in modern cars. Especially the engine ecu.

[Mike.Bray]

While I tend to agree w/narly1, it is funny though how much of the electronics is under the hood in modern cars. Especially the engine ecu.

True but you can't compare a battle-hardened OEM ECU to an aftermarket one like a Holley Terminator. Maybe the Dominator is closer to a factory ECU but still does not have the development & testing the OEMs put them through. Apples & oranges.

[jengum]

As most of you know I'm a HUGE fan of EFI and was an early adopter more than 30 years ago. I'm also a fan of the Edlebrock ProFlo4 system as it just works and works well. After over three years of development Edlebrock is ready to release their throttle body system which uses the same ECU as the ProFlo. For those that want the look of an old carburetor but the performance and drivability of EFI here you go.

https://edelbrock-files-v1.s3-us-wes...Street-EFI.pdf

Does this require an in tank fuel pump and fuel pressure regulator and return line back to tank?

[Blitzboy54]

Price point is pretty good too. I would never put another Sniper in anything. Complete junk.

[Mick40]

Hasn't this been on the market for years or is this an updated version?

[Jim Doak]

It's a new system and I've been following its release for several months.

I believe that it was supposed to be released late last year but has been pushed-back a couple of times.

I really like that the ECU is divorced from the throttle body. I had a Sniper 1 which had an ECU integrated with the throttle body and was VERY problematic.

[narly1]

Does this require an in tank fuel pump and fuel pressure regulator and return line back to tank?

Depending on your setup the fuel pump can be either inside or outside of the tank. There are dry sump systems that do not require a return line back to the tank, but a regulator is sill part of the set-up.

Earl

[Stangrob]

Back in the 90's I ran one of the original Holley Pro-Jection four barrel setups on a 455 Pontiac engine in a '68 Firebird. Open loop, fully analog. A few small pots on the control box for everything. A bit of a pain to tune, and it never ran as good as a well set-up carb, but at least it didn't have issues with vapor locking. So when I see the new Sniper setups I get flashbacks to my old setup, and I shiver a bit. However, I'm really looking forward to installing the Pro-Flow 4 that I picked up for my 331 build. I'm more than happy to have a pair of fuel rails to get sequential port fuel injection that's closed loop and self-learning. Yes, I know how to tune a carb, but I'm happy to make this pivot

Rob

[bobl]

So this seems just like the Holley Stealth EFI system, except the ecu is remote mounted which is a good thing. It appears they are using the FAST EZ EFI ecu (FAST is owned by Edelbrock). That ecu has been problematic in a lot of 8 stack systems, basically because it should never have been packaged with them. My experience with it is in that application. There is very little tunability beyond the basic parameters. It either works, or it doesn't. I'm making an assumption that capability hasn't changed. Time will tell.

Bob

[BEAR-AvHistory]

Can they be run as a dual quad system for a big block?

[weendoggy]

Still not in the realm of the Holley HP line. Also not fair to compare it to the Sniper(s). People buy the Sniper(s) or any other unit on cost, not performance. jmo I have a buddy with a Sniper 1 and just updated software to V2 and with some throttle blade adjustments, and the TB, have it running good. He's had it since 2017. I for one, don't care for it, but it's fine for a daily driver/cruiser. again, jmo

[rich grsc]

So this seems just like the Holley Stealth EFI system, except the ecu is remote mounted which is a good thing. It appears they are using the FAST EZ EFI ecu (FAST is owned by Edelbrock). That ecu has been problematic in a lot of 8 stack systems, basically because it should never have been packaged with them. My experience with it is in that application. There is very little tunability beyond the basic parameters. It either works, or it doesn't. I'm making an assumption that capability hasn't changed. Time will tell.

Bob

100% correct, the FAST EZ EFI will not work on a stack system... It's junk that I wouldn't even install on a lawn mower.

[gbranham]

Still not in the realm of the Holley HP line. Also not fair to compare it to the Sniper(s). People buy the Sniper(s) or any other unit on cost, not performance. jmo I have a buddy with a Sniper 1 and just updated software to V2 and with some throttle blade adjustments, and the TB, have it running good. He's had it since 2017. I for one, don't care for it, but it's fine for a daily driver/cruiser. again, jmo

But ProFlo4 and Sniper 2 are essentially the same price. ProFlo4 is actually cheaper if you consider it comes with an intake manifold that you'd have to buy to support a Sniper. And it's a far better system. So, I don't believe people are choosing Sniper 2 for budget reasons. I think they're doing it because they don't know ProFlo4 is a thing, or they simply don't like seeing fuel rails. Seems silly to skip ProFlo4 for that reason, but to each their own.

Greg

[ProfessorB]

But ProFlo4 and Sniper 2 are essentially the same price. ProFlo4 is actually cheaper if you consider it comes with an intake manifold that you'd have to buy to support a Sniper. And it's a far better system. So, I don't believe people are choosing Sniper 2 for budget reasons. I think they're doing it because they don't know ProFlo4 is a thing, or they simply don't like seeing fuel rails. Seems silly to skip ProFlo4 for that reason, but to each their own.

Greg

Not just an included intake manifold.... the ProFlo4 also comes with a distributor.

[maginter]

True but you can't compare a battle-hardened OEM ECU to an aftermarket one like a Holley Terminator. Maybe the Dominator is closer to a factory ECU but still does not have the development & testing the OEMs put them through. Apples & oranges.

This is a very true statement!! I have been working in Automotive Electronics and Safety for about 44 years. The design hardening, verification and life testing we do for any under hood electronics is well beyond what any After Market Supplier would be willing to do because of the cost, that we offset by volume.

Mark

[David Hodgkins]

You guys have me curious now. I have the Windsor BOSS 302 crate motor, rated at 340HP From ford. "B" cam, all forged internals. Considering the fact that the motor can accept supercharger as a future upgrade, which system would I be better off with? #35930, or #35940? It looks like maybe the injectors are the only difference, but the pictures on the site are not the same.

https://www.edelbrock.com/shop/fuel-...=1774464932370



EDIT: 35930 comes with 29 Lb/Hr injectors capable of 450 HP with 58 p.s.i. fuel pressure
35940 comes with 35 Lb/Hr injectors capable of 550 HP with 58 p.s.i. fuel pressure

[bobl]

You guys have me curious now. I have the Windsor BOSS 302 crate motor, rated at 340HP From ford. "B" cam, all forged internals. Considering the fact that the motor can accept supercharger as a future upgrade, which system would I be better off with? #35930, or #35940? It looks like maybe the injectors are the only difference, but the pictures on the site are not the same.

https://www.edelbrock.com/shop/fuel-...=1774464932370



EDIT: 35930 comes with 29 Lb/Hr injectors capable of 450 HP with 58 p.s.i. fuel pressure
35940 comes with 35 Lb/Hr injectors capable of 550 HP with 58 p.s.i. fuel pressure

Other than very low boost (3-4 psi) you will want larger injectors than the 35 lb anyway.

[Mike.Bray]

Sniper 1 Great idea, terrible execution

Sniper 2 Fixed most of the issues with the Sniper 1, timing control with optional Hyperspark distributor

Fast EZ Very rudimentary "self learning" system, not their best work. 100% will not work on stacks.

Fast Sporstman Tunable version of the EZ and a very good ECU. Capable of timing control.

ProFlo 4 Excellent sequential port injection system with timing control. IMO best bang for the buck and just works.

New Edelbrock TBI system I'm betting it will be a winner. TBI with the ProFlo ECU, software, and distributor/timing control.

[rich grsc]

Mike, you don't like the Holley Terminator X?

[FF33rod]

Sniper 1 Great idea, terrible execution

Sniper 2 Fixed most of the issues with the Sniper 1, timing control with optional Hyperspark distributor

Fast EZ Very rudimentary "self learning" system, not their best work. 100% will not work on stacks.

Fast Sporstman Tunable version of the EZ and a very good ECU. Capable of timing control.

ProFlo 4 Excellent sequential port injection system with timing control. IMO best bang for the buck and just works.

New Edelbrock TBI system I'm betting it will be a winner. TBI with the ProFlo ECU, software, and distributor/timing control.

Not that it matters anymore but Sniper 1 is also capable of timing control with the optional Hyperspark distributor. I've had no problems whatsoever with my setup, one of the lucky ones I guess.

Steve

[Bill Elliott]

I would not say luck. I have Sniper 1 with Hyperspark and love it. I have had no issues at all , although i did avoid any problems with internal pressure regulator by removing it and putting external on from the beginning. I think some people have problems with it because they dont always follow manufacturer recommendations, ie. clean power, and some don't take time to work out the fine tuning. Right out of the box it is driveable , but if you want good performance you have to work on the tuning. I have 3600 miles and it is running better than ever.

[Mike.Bray]

Mike, you don't like the Holley Terminator X?

I do like the Terminator X, I have one sitting here on my desk. Was going to swap out the Sportsman on the Cobra with it but since I got the Cobra tuned nicely I've decided to hold off for awhile on that project. So I'll fit it to my stack injected 427 SBC going into my 68 Camaro.

TBH, if I was doing it again I'd probably go with the HP over the Terminator as it's more industrial and reliable.

20260328_102642.jpg

[Bill Elliott]

What's the difference in the Terminator X and the Sniper?

[Mike.Bray]

What's the difference in the Terminator X and the Sniper?

Sniper is a throttle body EFI system (TBI) that looks kind of like a carburetor but contains injectors and an ECU for EFI. So a carburetor that works well. https://www.holley.com/products/fuel...ts/550-511-BXX

Terminator X is an EFI control system. It needs to be paired with an air metering device like a throttle body on an intake manifold or my favorite, stacks. https://www.holley.com/products/fuel.../parts/550-936

[rich grsc]

Ya, I thought you had one. Mine is still in the box too. The new engine won't be ready of awhile, and it may not go into the car till fall.

[bobl]

I just discovered Holley offers the terminator X stealth that uses the same ECU as the multiport terminator X. So there is a whole lot out there to choose from.

[bobl]

I do like the Terminator X, I have one sitting here on my desk. Was going to swap out the Sportsman on the Cobra with it but since I got the Cobra tuned nicely I've decided to hold off for awhile on that project. So I'll fit it to my stack injected 427 SBC going into my 68 Camaro.

TBH, if I was doing it again I'd probably go with the HP over the Terminator as it's more industrial and reliable.

20260328_102642.jpg

I used the FAST stuff since it first hit the market(early 2000's I believe), but when Holley introduced the HP EFI I found it to be a lot more powerful and user friendly. I switched to Holley and never looked back. You are correct that HP/Dominator are much more robust and have many features the Terminator X doesn't have, but Terminator X will take care of the needs of 99% of the customers.

[Mike.Bray]

I used the FAST stuff since it first hit the market(early 2000's I believe), but when Holley introduced the HP EFI I found it to be a lot more powerful and user friendly. I switched to Holley and never looked back. You are correct that HP/Dominator are much more robust and have many features the Terminator X doesn't have, but Terminator X will take care of the needs of 99% of the customers.

I started with the old Accel/DFI stuff way back, DOS based software and narrow band O2 sensors. Self-tuning? Ha! For me the Sportsman was a huge step up from what I was used to. Timing control? I never appreciated how nice timing control is until I played with it. The FAST software is easy to learn and use and I like the robustness of the ECU with it's metal case. I wish the Sportsman had sequential timing control though.

I've got the Terminator X and as would be expected it has a lot more features than the Sportsman. FAST was all set to dump a ton of money into developing new generation when Edelbrock joined the group and it was decided to focus on the Edelbrock line of EFI. I do like the Holley software and all of the features is has. On my 427 stack injected SBC I'll do sequential port injection and I'm planning on playing around with an input for the AC compressor and triggering a PWM output for the radiator fans. So I'm excited to get to playing with it!

[Blitzboy54]

I have the Terminator X Max on the truck build. Crate LS3, roughly 560 horse.

[bobl]

One last comment...Thanks Mike Bray for posting this. It brings up some other options that members may not have known about.

[NJMike]

Hello to all of you EFI guys,

I need some advice on EFI or carb decision. I met with my engine builder today, he is building a 331 Stroker using a 1968 Ford 302 block. I told him that I was planning on using the ProFlo4 system, he strongly cautioned me that it would need to be tuned by a professional tuner after he did the basic setup. I reviewed the installation instructions again and on the surface the basic instructions seem pretty straightforward, I wouldn't want to get into the advanced tuning section of the manual. I don't want to get in over my head with a system that requires elaborate adjustments, I haven't tuned a car since around 1977, probably before most of you were born (LOL), so the advanced tuning would be beyond my capabilities.

So please share with me your experiences of installing and setting up the ProFlo4 system.

Thanks in advance.

Mike

[narly1]

Novice engine builder here and I got it running all by myself. Had an issue where it would only run for a few seconds before dying out. Turned out the fuel pressure regulator was set too low. The initial set-up is all menu driven. Had to fiddle with the idle RPM a bit to allow the IAC room to work. I then put the engine to sleep for a couple years. When I went to run it again it wouldn't start. All 8 injectors were plugged with verdigris (aka green dead fuel gunk). Cleaned them out and it fired right up again. It will self-learn and run better as time goes on.

I did find this video online that talks about advanced tweaking which I think is what your engine builder is talking about.

https://www.youtube.com/watch?v=xxvthCv9fJE

This next video talks about advanced PF set-up in a Camaro, it shows a lot of the setting changes you might want to make and why:

https://www.youtube.com/watch?v=Pxue-91xZz8

All in all I think the average guy can get the system running their engine very nicely with a little bit of persistence and patience.

Earl

[NJMike]

Thanks Earl,

I appreciate your thoughts as well as the videos. I should have mentioned that I plan on using this strictly as a street engine, so I don't need to squeeze every HP out of it. The instructions read like if you follow the setup wizard you will have a good running engine and then they give you addition info for advanced users, which I am not. I think I'm going to stay the course and go with the ProFlo4 rather than a carb.

Thanks again.

Mike

[Mike.Bray]

You will be happy with the ProFlo4, it's a great system. Way happier in the long run over an analog mechanical carb.

[NJMike]

Thanks Mike

[jengum]

Does anyone have experience with the Edelbrock fuel sump...good, bad or indifferent?

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