Edelbrock Pro-Flo 4 EFI

[cycleguy55]

Is anyone running the Edelbrock Pro-Flo 4 EFI? This is a MPFI system that sounds like it could be a very good system.



https://www.edelbrock.com/edelbrock-...ifZW-fvmShO12Y

Reviews I've seen have been very positive:

https://performanceimprovements.com/...ions.%E2%80%9D

https://www.hotrod.com/articles/insi...ry-sfi-system/

https://www.enginelabs.com/engine-te...a-junkyard-ls/

Compared to my Holley Street Avenger and Performer 460 intake manifold, the Pro-Flo system is at least 1" lower, perhaps just a bit more. 0.25" comes from the intake manifold and another 0.75" from the throttle body vs carburetor. There's also an angled carb spacer in there that I wouldn't need with a throttle body. All of that would certainly help with my current tight hood clearance and allow me to run a bigger air cleaner.

I'd be interested in hearing feedback on real-world experience.

[eschaider]

What is the price tag, Brian?

Ed

[cycleguy55]

About USD $2250, less $100 if you don't need the Android tablet (I don't). Price includes everything you see in the photo - intake manifold, fuel rails, injectors, distributor, etc. Fuel sump is around $400 should you choose to go that route. More money than low end TBI systems, but far less than some of the systems that have been around for a while.

[eschaider]

Pricing is pretty good. I was going to suggest the MegaSquirt Plug and Play systems that use OEM Ford wiring harnesses. The box is a $1,349 purchase and you source a wiring harness from a salvage yard. The system uses all Ford sensors (or any other sensor you want to take the time to calibrate). You still need to find a manifold and throttle body so you will likely end up about in about the same ball park money-wise. Here is a link to the P-n-P system => MS3Pro PnP

The aspects I found attractive were the ability to run any engine by changing the displacement in the tuning s/w along with multiple engine fail safes to protect the engine from whoopses that cost rebuilds along with the traction control and knock detection and prevention systems.

A big unspoken but obvious positive was the ability to use an OEM Ford wiring harness rather than stringing my own. The OEM harnesses tend to have a very durable construction which is always appreciated and salvage yard pricing is cheap - sometimes as low as zero if you are willing to do the harness removal from the vehicle.

From an ease of use standpoint the ECU comes with a base tune, tuning software and data logging s/w that you can access with your laptop through a blue tooth connection. I think I paid something like $75 for the bluetooth gizmo to allow the laptop to wirelessly connect to the system.

The big drawback is you have to source the manifold and throttle body so the alternative you are looking at adds a very comfortable one stop shopping sort of benefit that is not insignificant.

To the extent possible you want to try to avoid the throttle body injection and go to port injection if at all possible. The port injection gives you a dry manifold so the usual fuel separation as you go around corners (in the manifold) does not occur and it allows you a much broader selection of injectors to choose from for fueling purposes.


Ed


p.s. Your pic of the system you are looking at does use port injectors so my comment about throttle body injection is off the mark, the system you are looking at does not use it — my bad.

[olddog]

No experience with Edelbrock's EFI, but I do not see a mass flow sensor. If correct then it must be using either speed density or Alpha-N strategy. May be capable of either.

Speed density uses a MAP and TPI and rpm to calculate or estimate the air flow into the engine. Large valve overlap causing very low manifold vacuum becomes unmanageable if the manifold vacuum is lower at idle and then increases off idle for a while before it starts to drop again. Then you have no choice but go to Alpha-N strategy or mass flow. Milder cams no problems.

I still like mass flow the best.

[eschaider]

+1^ on what olddog said. The Mass Flow (MAF) based systems are the most precise and they adjust in real time for atmospheric changes like temperature and altitude without the need to re-tune the car. You can also change cams, throttle bodies and even cylinder heads and the MAF sensor has you covered because it is measuring actual air mass ingested by the engine, informing the ECU and letting the ECU make all the necessary fueling decisions to support the new air flow.

Another nice attribute is the fuel management when the camshaft overlap, we like for the 60's muscle car idle sound, creates idle and off idle fueling problems. The Speed Density and Alpha-N systems experience an unpleasant personality for low speed in traffic sort of driving. The MAF based system makes significant improvements over the other two fueling models in the engine's low engine speed personality while maintaining correct fueling everywhere else also.

If it is important to you, the MS3Pro P-n-P system uses all three so you have a choice although like olddog, having used all three, I have a Mass Air Flow bias. Almost forgot, another consideration is the MS3Pro P-n-P system supports a flex fuel engine operation if you add a Flex Fuel sensor in the fuel feed line.

The big deal about the flex fuel option is you can run it as a 100% gasoline enigine initially and later if you find ethanol availability you can fuel up with the ethanol and the sensor will measure the % ethanol, inform the ECU and the ECU will adjust your fueling map(s) for the actual ethanol content in your tank.

Later if you need to refuel and no ethanol stations are available, you just fill up with old fashioned gasoline and the flex fuel sensor detects 0% ethanol (or whatever small number it actually is) and the ECU automatically adjusts the tune for the new fuel. It's actually pretty cool and lets you experiment. The other thing is the ethanol brings a free-be 100 octane fuel to the engine for less than pump gas.


Ed

[rads42]

Rookie question here as I know very little about fuel injection. Where does the O2 sensor go on a cobra with side pipes? I was looking at the instructions online for the Pro-flo 4 and it wants it past the collector. So there'd only be the little space between the muffler and collector and I assume you'd want that as hidden as possible so it would have to be between the body and the exhaust pipe. Seems like a pretty small space.

[Chicagowil]

Originally Posted by rads42

Rookie question here as I know very little about fuel injection. Where does the O2 sensor go on a cobra with side pipes? I was looking at the instructions online for the Pro-flo 4 and it wants it past the collector. So there'd only be the little space between the muffler and collector and I assume you'd want that as hidden as possible so it would have to be between the body and the exhaust pipe. Seems like a pretty small space.

The O2 sensor needs to be just after the junction of the header pipes. On my CR 1 it is located just before the muffler. But CR di make one mistake- they have it angling up instead of down. This will cause it to collect moisture and over time destroy the O2 sensor. But they did it to conceal it and fit it under the edge of the body. Still not right. But on a low use and fair weather car- not as critical.

I had looked at this same system for my car as well. The CR1 has the 5.0 mounted pretty high up in the engine compartment. As I was using a Kenne Bell supercharger- there was no way to fit it under the stock hood. But at a package price of about $2,500.00, I decided to modify the hood to clear the S/C. Since I already had the S/C which adds over 100hp, I modified the hood. But I thought the system was the best of the retrofit EFI systems that will give you the "original look" of a carb with the tuning of EFI. It does, as was mentioned here, have limits of performance to more highly modified motors without custom tuning.

The next best but considerably more expensive choice is the Weber style EFI systems. But at over $4k and much taller, it causes one pause.

Thom

[eschaider]

For a carbureted engine you can put it fairly far down the exhaust system because it is only telling you what the AFR is. It is not telling an ECU that is making fueling decisions and changes in real time.

That said, even on carbureted engine, you still want to keep it away from the end of the exhaust path because of the back flow of ambient air. The ambient air will produce a fake lean reading that you will chase with larger jetting to correct. All the time you will be making the engine run richer than it should because of the ambient air the sensor is sensing.

On EFI engines you want the sensor to be within 12 to 18 inches of the exhaust valve. The reason is time delay. Further down the exhaust, the event the sensor is reading about has occurred so far back in time the the fueling correction no longer has any meaning except perhaps in a stationary power plant engine that continuously runs at the same rpm.

In an automotive application where load and engine speed are continuously changing so to is fueling demand. To properly monitor and respond to changes in load and rpm the sensor needs to be 12 to 18 inches from the exhaust valve. The easiest way to do this is weld an O2 sensor bung into one tube. The problem is it only monitors a single cylinder.

The easiest fix is to make a rectangular spacer that fits between the header and the side pipes with the center hollowed out to allow all four cylinders to mix up their exhaust pulses. Place the O2 probe so it's sensor is in this chamber and you will sense the entire bank in real time soon enough to make fueling changes that will make a difference. Be sure to correct the header / side pipe dimensions to correctly reposition the side pipes outside the body.

The absolute fix is to use an O2 sensor on each exhaust tube close to the port like the OEM manufacturer does during their EPA fuel system calibration. This is expensive and unnecessary for our use.

Sensors in the collectors or anywhere that is not 12 to 18 inches from the valve will give false reports to an EFI system and forever keep your engine out of tune. There is a reason the OEM's place the O2 probes so close to the exhaust port.


Ed

[fastd]

this is a pretty trick set up...I like the manifold that injects directly into the ports...So just air comes through the throttle body? Pretty cold.

I have the Holley Sniper but this looks superior. Good luck.

[Steve Gallegos]

I run the old Edelbrock Proflo 2 system. it runs nice, but it's getting old and I can't find anyone who has the computer software to chassis dyno it. So, I'am thinking of switching to the Proflo4. Edelbrock has a sale coming up for labor day. For my ford engine the cost now is $1999.00 with tablet. It should go down about 10 to 15%. The guys I know who have the 4 love it. Some have changed from another system that ran poorly.

[Luce]

the large duration cam and speed density incompatibility is way overstated. Yes, if you have one of the "self learning" systems, they will not "learn" how to behave.

With megasquirt, you can simply close the window on the self adjusting below 2000 RPM and manually tune those areas. You will need to run a little rich at idle, but not so much it'll load up.

If you have any electronics background, you can make a much nicer harness that actually fits, and save $600 soldering the ECU up yourself.

I haven't fallen into the bigger is bettertrap. MS2, batch fired for me thanks. My 427W doesn't have 4 cams with variable valve timing and multiple boost controllers. Just fuel, spark and control the fan.

[ono1]

I run this system and I am very happy...I had a 750 double pumper before....this is smother and more responsive

[ono1]

just make sure o2 sensor is angled correctly

[Chicagowil]

Another option is this Weber style system.

https://www.ebay.com/i/164092002341?ul_noapp=true

You would have to add an ECU. But it is really nice looking!

Thom

[Luce]

https://www.ebay.com/itm/Ford-351W-W....c100005.m1851


I bought one of these for SBC and put it on a 383 in a 71 vette. Very well mannered. I did some trickery and swapped the L and R sides so the fuel rails were in the middle and better aimed at the intake valve as they should be.

[cycleguy55]

I like the 8-stack look, but SBF systems aren't going to work on a 460. Something more like this:



I like how the stacks are canted toward the centre - better fit under a narrower hood scoop, plus presumably a straighter shot at the valves.

I have no idea why their URL references BBC, but here it is anyway: https://specialtyvehiclebuilders.com...-system/v/5001

Regardless, this system is $$ multiples of the Edelbrock Pro-Flo 4 system by the time you get all the necessary bits and pieces to make it work.