so much info on EFI. What to choose

I went from a Torker 440 with an 800 Holley to a Performer RPM with a 750 Edelbrock 20 yrs ago. Then about 10 years ago I swapped out to a CH28 Dual 500 Eddy setup and have been happy with low rpm torque response. Now I wanna go to EFI. I have a friend who wants me to go Holley Sniper route. I kinda wanna keep the look of Dual TBI for that aggressive underhood apearance but will sacrifice the look for performance and thats why I kinda like the Edelbrock Pro Flo4 XT. I will go the route of replacing the fuel tank with an appropriate tank with an interior fuel pump and a return line. I did some forum searches and found that the electrical wiring is finicky with the sniper, I am also reading you need to have a stout wiring system and grounds. I have that covered in all respects with grounds everywhere, 100a Delco Remy alternator single wire. I have xenon bulbs complete with ballasts and the factory mechanical clutch fan and an aftermarket 12" Hayden pusher fan which I turn on when I need. I have a cassette deck and two 6x9 speakers. The symphony is under the hood.

She's a weekend driver, Isky 280 Megacam, 2200 stall converter, 3.55s with Gear Vendors OD. 10.5:1 w/ aluminum RPM heads. Going from HP Man's to Hedman shorties this coming winter.

Side note...I had a 505 that I was building but a forest fire ended those dreams. The crankshaft is toast and therefore the engine block is also. I do have the parts from that engine build (they were in another storage area) and don't know if installing the B&M 3000 Holeshot, the 540 Roller Hydraulic camshaft and lifters (no way are the stock springs on the RPM heads gonna work with this), and roller timing chain....how well it would work with the EFI.

I dropped quite a bit of info in this but I would rather be clear than not

There are some post on here from members who have used the ProFlo4. I think there were some minor issues around air filter placement. But my personal thought of that unit is that it was designed for visual impact more than performance - particularly when you compare it to other tunnel ram style efi intakes on the market.

As far as efi in general, port injection tops the list of the way to go but the cost reflects that. The Sniper TBI units have good offerings at lower cost. I think following the manufacturers recommendations to a T are critical for trouble-free installation and operation.

I would call FITECH and look at Holley EFI (both companies) for dual throttle bodies, both dry and wet (with injectors inside of them).
I bought and installed a Holley dual dry throttle body system for one of my local customers that wanted it for his 571 C.I. street hemi motor, I bought a KB Stage 5 dual inline intake that is made mainly for EFI systems, I can't remember who I had set that intake up for the direct port injectors That motor made 799.6 HP at 6500 RPM and more torque than HP, good vacuum at idle 900RPM and it idled like your grandpa motorhome motor home did
Throttle injectors supposedly don't like dual plane intakes like yours The direct port systems don't know what type of intake you're using, I would go with the direct port injectors on your intake and run both throttle bodies hook up 1 to 1 That type system is a lot more tunable also
IHTHs

Just an opinion but I would prefer carbs over dual throttle body injection.

I went to Holley EFI/Multi-port but only because I wanted to run it on E85.

The Holley Sniper is a really good product and Holley has continued to expand the product line so now it is a complete bolt on kit including the ignition system. You do need some computer knowledge to install the Sniper. If you aren't up to speed on how find files on a hard drive or move files from the internet to a SD card then you'll need help. You'll need a Windows laptop so you can interface to the Sniper and program it. The Sniper electrical install can be tricky, especially on a Mopar. There are several ways to solve the puzzle of IGN 1 and IGN 2 so if you decide to go that way just post a question. I have various Sniper install and tuning videos on my website and youtube channel.

You might consider having fuel rails put on your current manifold and run two 4 barrel throttle bodies. You would have port injection and dual throttle bodies. I run a setup like this but on an old Holley Pro Dominator tunnel ram. I think that would get you the best performance, I do not know how it would work out from a money standpoint. In 2017 it cost me $450 to have my intake modified for fuel injectors and -8 fuel rails.

There is a lot of good systems out there. If its an OEM engine that makes over 10 inches of vacuum then FI tech might be an option, but i wouldn't suggest them by any means. I put a Holley dominator on mine, lots of guys around my area running their systems and are familiar with them. The Holley snipers seem to be hit and miss with RF interference, but work great when they work.

If I lived in the US I could probably find a reputable shop to do that kinda work but I live in Greece and I can't trust a shop to that level. Plus its theory, its piecing together injectors,throttle bodies and software while basically making it a frankenstein situation. I prefer a bolt on application that the manufacturer can't turn around and say "its not our product's fault because you aren't using our dedicated manifold/injectors/TBI"

I was a Microsoft Certified Systems Engineer in the past, mostly forgotten but I remember some stuff. I build PCs and tinker with electronics. This isn't a problem for me.

I am trying to get the most out of my weekend bruiser. My fuel has consistently been over $7 a gallon here in Greece. This last weekend I killed a battery cranking for 30 minutes, removing fuel inlet pipes and filling fuel bowls with a syringe. Using starter fluid and constant cranking. I finally caught a lucky break and she kicked over....In the winter she can sit for a month and I can giver her 2 pumps and turn the key and she fires right up but the Summer was very hot here and even in my garage, the fuel evaporate after a weeks time. They are forcing me to go from Hoistorical plates to State plates and my registration goes from $40 a year to $1800 a year. So I might as well make use of the State plates and travel more with my car, get some better fuel numbers

You should be good to go then. The Holley EFI system is all based on Windows so you need to be familiar with moving files around, using pull down menus, using a mouse to drag and drop and stuff like that. It is all routine stuff for someone who uses Word or Excel on a regular basis but I've run into a ton of car buys who have no idea how to attach a file from their hard drive to an email.

Having spent a lot of time in Greece and knowing how consistently hot it gets there in the Summer, it can be brutal on our cars.

If it were me, I would go with port EFI with dual (air only) throttle bodies. This will retain your dual quad look that you want, and allow for greater tuneability, cyl to cyl capability and allow for growth down the track.

The heat can and does affect the throttle body mounted ECU on the Snipers and FiTechs.

Just my

I have installed and messed with both Sniper, and FiTech both have performed well and since you have the dual quad intake a pair of bolt on throttle bodies would be easy and quick. I would prefer the FiTech for one main reason, it has the capability to set failure codes to tell you what is wrong with it. For some reason Holley systems cannot do this. Failure codes have been with OEM automotive system since the 1980's Holley it is time to get with the program. As a technician trained to work on OEM EFI systems, failure codes are how we fix them. If you have an issue with a Holley system, yes it can be diagnosed, but the skill level required is much higher. And I have very mixed results talking to either companies technical assistance over the phone, long wait times and sometimes it seems to me I know more about the systems than they do. Several times I have offered to email scope traces of the suspected components, and none of the tech people had any training or knowledge on scope patterns. As far as performance it has been shown many times that a well tuned carb will make a little more HP than EFI, I doubt that you could feel the difference driving the vehicle. I would also recommend, when you set up the system use the computer to adjust the ignition timing. The advance curve is a lot more of the drivability than the fuel curve on a lot of performance street driven vehicles, computer makes it very easy to tweak the ignition timing.

You could still source everything from Holley to maintain vendor support. But I do understand finding a shop to fabricate the injector rails could be difficult in your situation.

I built my entire system(the ECU was a kit) so I can only turn to the guy in the mirror in most situations lol.

I work with OEM EFI cars as well. Personally rely on data list more than codes (as many issues won't/take forever to set a code for anyway).

Don't find it necessary for aftermarket efi to have this but guess it could make some diagnostics easier.

[quote=LAD 524

The heat can and does affect the throttle body mounted ECU on the Snipers and FiTechs.

Just my

[/quote]

and my hood doesn't have fresh air induction which might have improved this problem, I would love to install a GM style cowl induction like the 70 Chevelle has but I have done away with the factory brake booster setup and my headlight doors are being converted this winter to electric actuators. I would need to install a 2" electric throw actuator but thats a whole other topic to bring up at a later date. Lets not open too many cans of worms

Well, it sounds like you have not used one of the current EFI offerings...So there are things to consider.

Self learning
Software update ability
Amount of wiring needed to hook up and install
Throttle body options vs. modifying your intake and adding rails to it....
Ease of programing
Expandability....Many are just a boxed offering and cannot be used but for one purpose, others are not.

I have used Classic FAST, and also their newer TB style as well as a Holley Sniper....

I really like the Holley over FAST for a few reasons....The software is awesome. It keeps the learn table separate from the base table, you can merge them if you want and clear the learn table, which I really like. Or leave it be and watch it build the whole table as it passes thru all the different cells.

And for it to learn, you only need the cursor to flash thru that cell, it does not need to sit there for 5 mins to determine the VE....

You can use a laptop with the Holley Sniper if you want, but most of the base operations are accessible thru the hand held..

I forgot how many wires were needed to hook it up, but it wasn't much, had it running in like an hour.

And the data logging with the Holley is very good, set a sensor reading to trip it, and go look at the logs...Just super easy.

The only thing that worries me about the Sniper is the ECU is built into the TB....The later/more expensive models they divorced it.....If your under hood heat is an issue.

Loads of information...seems most here have gone the route of FAST or Sniper. I wonder why the Edelbrock isn't on anyone's preferred installation.

What do you guys do for the fuel supply part of the EFI? For those using the Holley, have you purchased the new fuel tank or used an aftermarket sump pump. What size line do you have to plumb for the high pressure? 3/8"? 1/2"? I perused Summit last night and saw some nice tanks from Aeromotive. What do you suggest for the tank?

So for a fuel system for efi, I really like the Aeromotive A1000....And one of Aeromotives universal bypass regulators. If its a throttle body type system, I return the fuel off the regulator, but dead head it up to the TB for a nice clean install. The regulator down on the frame rail, or there abouts along with the return line, and then up to the throttle body with one line, typically AN08....


The universal regulator comes with two springs one for efi, one for carb.....comes in real handy, and I plumb it all so I can switch between them....My Big Hemi is done this way and so were some of my previous setups.....Full on efi with rails, well, that you will have to do the traditional way...

If it is a popular car then Holley will have an EFI gas tank available for it. I'd use the integrated EFI gas tank if possible since it will have the pump and regulator built in so you just have a single high pressure line to run from the tank to the throttle body. 3/8 inch line is more than enough for a street engine. In fact, 5/16 will work for most street cars.

I had a Holley analog setup decades ago and it worked well, until it didn’t. I liked it and get why you’d want one. That said, if starting after sitting is a big driver for spending the money, I’d rather just dump the gas in the carbs and go on. I’m not getting taking the fuel lines loose or just filling the bowls. Gas down the throat will do it.

You can buy a lot of gas for what this will cost. A lot. If saving money is the goal, add up how much gain you’d expect and how long the payback is. Be realistic as to how much you will drive. I’ve used classic big block mopars as three season drivers this century. Gas cost wasn’t as big of a deal as it might seem.

Agreed on consideration if cost is the driving factor.

Regardless of climate, if you're killing batteries, cranking for 30 minutes, removing fuel lines and using starter fluid.......... you have other problems that EFI will not solve.

Even if 120+deg ambient, you shouldn't need to do the above.

she has zero problems otherwise, she handles temps fantastic, she can lay down rubber sideways through an intersection, and most of the time I am just driving with the front 500cfm carb, picture below is with just the front carb, 70mph, 180º water, uphill, and spinning that 440 1900rpm with the Gear Vendors kicked in. I have tinkered with the thought of running an external 7psi fuel pump but quickly been disparaged by reading people who went down the road before me and ended up with burned out fuel pumps due to excessive heat. I am not doing it for money savings, is it a perk..yes but not the sole benefit. If that was the case I would put my single 4bbl Performer RPM back on with an AFB. I want to evolve her, bring her more up to date with technology. There is a group here called SpeedSector who drive around Europe and participate in endurance races and I would like to be able to join that next year. They mainly allow super cars to enter but they seem like a good group of people who love to tour. I already upgraded my brakes to a Hydroboost and have the Stainless lines ready to go in this winter with a few other upgrades. When it costs $170 to fill up your tank (albeit 95 octane) You wanna maximize your fuel, especially in an endurance race. Now don't get me wrong...my ride isn't ProTouring....YET! I am looking at changing over the upper and lower control arms but I need to find a fabricator friend first over here.....

They had the Gumball 3000 rolling through here to Mykonos in 2019 and I wanna jump on the bandwagon for the next time it comes through (I am accepting sponsors from now )

Right after the EFI install its on my list to install a Dakota Digital Dash and replace the factory console auto shifter with a custom console but thats a 2024 problem.


Next question as I am watching Youtube videos about EFI installs. Do I have to replace the MSD 6AL box and the matching HEI distributor?

Different systems use different ignition parts depending on which one you choose.

I'm sure every system has its way of managing the ignition. I'm using a FAST XFI and can speak to how it works the ignition system. I chose this system because I already had experience with the system, because they are an older system they can be found cheaply(paid about $500 for mine used), and there is a strong knowledge base out there for support. So based on the FAST EFI system a stock or aftermarket distributer and MSD box will work in batch fire or unsynchronized sequential mode. Depending on how advanced you want to set up the system, a dual sync distributer(both cam and crank signals) or a modified stock or aftermarket distributer with a crank trigger will give the proper signals to work in a true sequential mode. The distributer can be lock down and the computer can manage the distributer advance.
Just about any injector, throttle body, and sensors can be used with the system. If you have any wiring skills its not to hard to make your own harness. I had bought a custom unterminated long harness and mounted the FAST XFI above the glove box. I added a flex fuel sensor and used another stock hard fuel line run next to the primary line as a return. The fuel tank is a Tanks inc EFI compatible with an in-tank EFI specific Hellcat pump and proper in-tank baffling. The EFI can even PWM control the fuel pump and I also use it to control the gear vendors OD in place of the Gear vendors computer. In my case I had bought an Edelbrock intake that had the EFI injector holes already machined and a matching set of rails.

Based on your comments above I would maybe just look at flipping over to a Tanks Inc. fuel tank that features an internal electric pump and a return line system. This will fix all the issues you currently have, be totally reliable as the pumps they use are Walbro which is what most OEM's use now, and it will set you up for moving to fuel injection should you change your mind later. You can set it up, see if it meets your needs, and if not you would have had to take those steps anyways (if you wanted to do the fuel injection route correctly).

Just a thought...

Thats a beautiful setup...I wish Edelbrock made a CH28 with fuel rails already machined into it. I would probably have gone that direction. Thank you for the explanation on the work you did. Truly a masterwork.

I still think the selling point for the ProFlo over the competition is the location of the ECU. I want to mount it behind the dash next to the MSD box and have it far and away from heat and moisture. Maybe if I had a ram air induction it would sway my decision. Why couldn't the Sniper have an optional removable ECU with a dummy cover for the TBI and wiring for remote placement. They should look into that

I used a Holley throttle body Sniper kit for one of my customers 350 Chevy stroker pump gas motor for his 1972 Chevy 3/4 ton standard cab 4x4 with an automatic with power brakes.
I used a small set ( not a big racing set) of the Trick Flow heads and increase the stroke to make the motor have 383 C.I. with the block bored to 4.030, nothing exotic at all. I installed the Sniper kit on the engine dyno and everything hook up easily, that motor made 425 HP at 6000 RPM on the third pull using Oregon pump swill . I didn't flog the heck out of the tune up on the engine dyno due to it having open headers and fresh air blowing into the dyno room. I will finish the final tune up in the truck.
I will recommend and buy those kits again: up: IHTHs

i would think mounting the ECU next to the MSD would create a bunch of electrical interference ?
but then, i couldn't tell you how far away from each other they should be....
please correct me if i'm wrong !

They do, the Terminator X Stealth systems have an external ECU that you can mount in the car and still have the look of a conventional carburetor/Sniper system.

In his application I don't know how well they would work since they have the footprint of a 4150 Double pumper so they take up alot more room than the regular sniper that is more like a edelbrock carb in shape.

They look really good though, if the install is clean its hard to tell at first glance especially from the drivers side where there is no wiring. The lack of accelerator pump gives them away pretty quick once you spot that.

This is one on a Pontiac engine I saw on drag week.