Aftermarket EFI installation - Questions

Hi Gents,

So after a lot of daydreaming and thinking, I'm contemplating an EFI swap. I'm actually contemplating several things...EFI swap, 3G swap, Serpentine drive swap, etc. Then there's an AC install, and possibly a gear ratio swap...the list is potentially endless, I guess.

Anyway, I know there are some members on here that have done this already (Jacob84, and others?), and some that are planning on it soon (Rusty_S85), and then several of you that have done factory EFI swaps.

I've been reading about the various kits for hours, and it basically comes down to the Holley Sniper, the FiTech #30003, and Summit's MAX efi 500 kit. Oh...and I guess possibly a factory style EFI w/MAF swap, maybe.

The Holley Sniper kit seems to be regarded as the best-ish of the bunch, but it's also a little more expensive. I like the simplicity of the FiTech kit (and the price), but Google searches seem to bring up a lot of complaints. Then there's guys that say most of the problems have to do with user errors and installation errors...I dunno. It's hard to read. I'm not opposed to a factory style EFI w/MAF swap...the trouble is finding good parts to use. Maybe somebody could tell me what I'd need to do this? Is it tunable?

I'm mainly looking for input, or guidance on the basics of the aftermarket kits. I guess I'd need something similar to a factory fuel supply system? With an in-tank lift pump, which supplies a high pressure pump which supplies the throttle body unit?

I've read reports where bolt-on aftermarket EFI systems should not be used with dual plane intake manifolds (which I have). However, I've read where people have installed them with dual planes and had no complaints.

I don't dislike my Holley carb, and it actually works well, but I'm much more comfortable tuning EFI. I've done quite a bit of this in the past.

I'm not even 100% sure that I will even do this...as I said, right now I'm just exploring the options, and looking for pros, cons, and real world experience and results.

Factory EEC-V EFI is tunable, but it isn't cheap.  I think I paid $600 for the hardware and software to do it, not including the EFI stuff itself.  And then you have to tune it, and I don't think it is anything nearly as easy as with an aftermarket system.

However, when you are done you have something that you could take to most mechanics and have the codes read and parts replaced.  I'm not sure how true that is of aftermarket.

Most of the aftermarket I've seen is throttle body rather than port injection, so properly set up the factory stuff will be more accurate.  But the aftermarket will still be better than a carb, so the ease of installation and tuning may be worth it.

For a fuel system, I went with the later fuel delivery modules.  They have been used for many years, and much more recently than the Bullnose stuff, so should be available much longer.  The only issue is making the sending unit work with the Bullnose gauge, and a Meter Match does that.

Gary Lewis wrote

For a fuel system, I went with the later fuel delivery modules.  They have been used for many years, and much more recently than the Bullnose stuff, so should be available much longer.  The only issue is making the sending unit work with the Bullnose gauge, and a Meter Match does that.

Do the later fuel systems have enough pressure that a second fuel pump is not required?

Where did you install the Meter Match module?

Yes, they do - at least they have enough pressure for the factory EFI systems, although I don't remember what that is.  The Fuel Delivery Modules have the pump, sending unit, and switching valve in them.  So you have two nylon hoses, supply and return, with a wye to go to the front tank if you have two tanks - which you won't have.  Right?  Anyway, everything is done in the FDM.

But, if you are running only one tank then you do have more options that those of us with dual tanks.  No need for the switching valve, for instance.  So grafting an aftermarket pump into the existing sending unit is reasonable.

As for the Meter Match, I put it under the steering column.  Drop the filler panel under the column and there it is in case you want to recalibrate it.  You place it between the sending unit and the gauge, and you need power and ground as well.  Since you have to calibrate it after installation you don't want it in an inaccessible place.

Speaking of which, you have three possible set points: Full; Mid; Empty.  You don't have to play with Mid, but you do the other two.  But Mid helps as the potentiometer is apparently not linear and the gauge will drop pretty rapidly and then stay just above Empty for a loooooong time.  But setting Mid helps that.

Ford changed from the external frame mounted pump a reservoir/switching valve for the 1990 model year to the FDM design. If you have the large opening fuel tank(s) the FDM will go through the opening, but the alignment tabs are wrong. A 1990 up tank for the same chassis will go right on with no problems and if you can find a matching filler neck then the whole system will be updated like I did with Darth.

Ok, understood. So the later in-tank fuel delivery modules are putting out something like 60+ PSI then? So no need for a booster/high pressure pump on the frame?

I have the old style tank with small opening, but that's fine, I wouldn't mind going with a later tank and fuel delivery module if all I need is a Meter Match to make my gauge work.

I'm just looking for the simplest of all solutions here, should I decide to do this.

Right on all counts, Cory & Bill.

Big Blue is sporting mid-90's tanks, FDM's, & filler necks.  And the plumbing is all new nylon hose with the proper connectors.  Makes it simple to support later.

Oh, I forgot to add, if you shop around there are good deals on the tank with the FDM installed.  I got the two of them shipped to me in one box for quite a bit less than the two would have cost individually.

Gary Lewis wrote

Right on all counts, Cory & Bill.

Big Blue is sporting mid-90's tanks, FDM's, & filler necks.  And the plumbing is all new nylon hose with the proper connectors.  Makes it simple to support later.

Ok, I guess I better do some research on installing the later tank then, as I'll have to make sure I can use a later model filler neck and hose, etc. Swapping them on a Styleside truck is probably no problem since the bodies didn't change much. On the 1992-1996 Flaresides, I'll have to check and see if I can get obtain/use a filler neck from one of those generation beds. Hmmm.

Thanks for the info Gary.

Where the sniper gets its following is its all self contained.  The ECM and sensors are with in the unit itself and all you have to hook up is a key hot, battery hot, battery ground, and a rpm signal and you are running.  Everything else is optional and adds to the ability of the sniper.

Holley also makes the Terminator that has an externally mounted ECM that you can mount anywhere you choose but it involves bundles of wires and large connectors.

The OE system you can run and Holley makes a Terminator wiring harness/ECM to hook up to the OE EFI system making it more like the sniper/terminator when it comes to tuning and data logging.

If I had a OE EFI system I would go the Terminator ECM/harness route.  You can now data log and make changes via a hand hell or through a laptop.

But if I did not have EFI nor the EFI components I would go with the Sniper/Terminator as its more cost effective compared to sourcing OE EFI parts and then paying for the Terminator harness on top of it.

I personally picked the 4150 Sniper, it looks like a Holley 4150 double pumper but that wasnt the reason why I picked it, I picked it as it was the only Sniper Holley had with the Ford kick down hook up for a C6 transmission.  The plain Sniper doesnt have a Ford kick down but does have a TH250/350 / 700R4 attachment points.  Same with the Edelbrock Proflow 4 which is true fuel injection, it does not have a Ford kick down attachment and you will have to run a universal throttle cable as the intake on the ProFlow 4 is a high rise air gap like style.

FiTech I installed 4 of those units some 4/5 years ago now and had nothing but problems with them.  Every one of them had failed injectors, every one of them required sitting on hold for 2 to 4 hours to get a walk through of tuning the FiTech as the system on FiTech is a bit more complicated than compared to the sniper.  The Sniper complaints online are typically user installation error as Ive installed some 5 or 7 Snipers after we stopped selling FiTechs and havent had one come back with an actual issue.  Had one come back but the guy swears up and down the FiTech is running lean causing his engine to over heat.  Problem is the Sniper is idling at 12.8:1 which is a little rich so there is no way it is the Sniper causing that issue and the guy refused to let us pull the engine and do a tear down and find out why its over heating.  I have heard FiTechs are better now but I havent installed any as the sniper is just such a better system in my eyes.  FiTech is what I thought of years ago for my truck but after 4 installs all had injector failures I said nope.

The main reason the FiTech system catches my eye is that it's smaller (they have the #30003 EFI kit, which is max 400HP). I will probably go with the Holley kit if I do anything at all, but it just bugs me that they don't have a small 4bbl version...they're all 200-650HP, or larger. My 302 (now 304, I guess) just barely made 300HP on the dyno, and 99% of my driving will likely only use half of that...or between 100-200HP. I am never going to be at 5500 RPM in this truck, ever. I spend most of my time in the 1500-2500 RPM range, and once in a while hit 3000 RPM. Maybe one of the Holley Sniper EFI 2300 kits would work better for me...just need the 2V to 4V adapter plate.

I was reading about adding the progressive linkage to the 4bbl Sniper, and it seems like a great idea, but then I found out that the ported vacuum for the distributor advance is at the back of the unit. So, the progressive linkage is an excellent option, as long as you're not using traditional vacuum advance like I plan to.

Hmmm....more reading is in order, I guess.

Obviously like most aftermarket stuff it is aimed at brand C engines, the ones with the distributor on the wrong end.

Rembrant wrote

The main reason the FiTech system catches my eye is that it's smaller (they have the #30003 EFI kit, which is max 400HP). I will probably go with the Holley kit if I do anything at all, but it just bugs me that they don't have a small 4bbl version...they're all 200-650HP, or larger. My 302 (now 304, I guess) just barely made 300HP on the dyno, and 99% of my driving will likely only use half of that...or between 100-200HP. I am never going to be at 5500 RPM in this truck, ever. I spend most of my time in the 1500-2500 RPM range, and once in a while hit 3000 RPM. Maybe one of the Holley Sniper EFI 2300 kits would work better for me...just need the 2V to 4V adapter plate.

I was reading about adding the progressive linkage to the 4bbl Sniper, and it seems like a great idea, but then I found out that the ported vacuum for the distributor advance is at the back of the unit. So, the progressive linkage is an excellent option, as long as you're not using traditional vacuum advance like I plan to.

Hmmm....more reading is in order, I guess.

You dont need progressive linkage.  Holley in facts stresses to not do progressive linkage as the sniper is designed to work on all four barrels at the same time.  The fix Holley came up with for correcting the stiff pedal and the sharp break away when trying to lightly apply throttle to leave a red light where it goes from 0% TPS to 50% TPS is the throttle extension lever which is what I bought.  I've installed these in all vehicles with a stiff pedal and it fixed the problem to the point where it feels like you almost dont even have a return spring in most cases due to the extra mechanical advantage it gives you.

On the power output, long as you are over 200hp the sniper will work great.  Look at it like this, the less fuel you need the shorter pulse width the injectors will operate at which means less heat in the injectors and more longevity.

Like wise you are correct, the timed spark port or ported vacuum operates on the back two throttle bores and the use of a progressive linkage will delay vacuum advance.  I believe the Sniper Stealth is the same way as ported vacuum is still on the back of the throttle body.  How ever where the Sniper Stealth is better is the manifold vacuum port for PCV/brake booster is situated on the rear bores just like the standard Sniper but the IAC is relocated from the rear bores to the front bores.  This actually removes the risk of gumming up from the pcv fumes being sucked past and through the IAC.  This is why I will be using the rear manifold vacuum port for PCV and be using the OE vacuum tree in cylinder 4 intake runner for my brake booster.  I may run a Tee and run my brake booster to the PCV line but I dont want to be using multiple tees as that increases the risk of vacuum leaks over time.

For my build, most of my driving will be 1,400/1,500 rpm to 2,750 rpm which is street driving and highway driving up to 75 mph.  The cam I am running makes power 1,400 - 5,400 rpm and we all know the C6 transmisison out of the factory shifts out at wide open throttle at 4,500 rpm.  I will be having broader performance here in Texas custom build me a C6 with a E40D planetary gear set along with him tweaking the governor to get me a 5,000 to 5,500 rpm wide open throttle shift point.  My cam with recommended valve springs will float the valves at 6,000.  The springs I got from AFR are like 10 lbs heavier than recommended so I should be good there and my roller lifters are the 302H rollers that are supposed to be stable to 6,500 rpm.  I feel the sniper will be a great addition to my build and my goal was always 300hp but realistically if everything works right I could very well see 375hp or like the engine builder I know he says I might even hit 400hp if I am lucky.  I dont want that much power though cause this is a truck that will be driven empty 80% of the time.

The FiTech does have a smaller system for the 4V setups, Holley goes to a 2V setup for lower power engines which does suck for people with a 4V intake.  Both FiTech and Holley uses GM components, for example FiTech uses LS6 injectors last I heard.  Holley uses GM injectors but I dont know what they are for.  Holley wont really give us the correct part number for the injectors but we know they are GM though.  The TPS and IAC are both GM as well so sourcing parts for many things is actually quite easy as you just pick up a GM part from the local part store.  The Injectors on the holley is a bit harder cause they swear the injectors are special built for them but FiTech told us the same thing but then told us that they are basically LS6 injectors another time.  So I dont think Holley has special injectors either they just dont want us taking the units apart and servicing them ourselves vs mailing them back in for repair.

But I think the sniper would work great for you regardless of how much power your engine is making.  I doubt that 327 sbc I threw the sniper on was making much over 300hp if it was even making 300hp and it ran great.  Was very throttle responsive more so than the OE 4V carb.  It also idled so much smoother with the IAC taking over to maintain idle speed vs the mechanical idle speed stop.

85lebaront2 wrote

Obviously like most aftermarket stuff it is aimed at brand C engines, the ones with the distributor on the wrong end.

The standard sniper is as it doesnt have a ford kickdown linkage for Ford automatics.  The Sniper Stealth actually has the Ford kick down linkage so I feel the Sniper Stealth 4150 is more of a universal setup designed to also work with Ford automatic transmissions why the standard sniper is more geared towards just chevrolet setups.  You could still make the standard sniper work with switching the ford kick down to a cable and attaching the cable to one of the holes for the TH250/350 or 700R4 throttle cable hook ups.

Rusty_S85 wrote

The fix Holley came up with for correcting the stiff pedal and the sharp break away when trying to lightly apply throttle to leave a red light where it goes from 0% TPS to 50% TPS is the throttle extension lever which is what I bought.  I've installed these in all vehicles with a stiff pedal and it fixed the problem to the point where it feels like you almost dont even have a return spring in most cases due to the extra mechanical advantage it gives you.

Is this the throttle extension that you're talking about?

https://www.holley.com/products/fuel_systems/carburetor_components/brackets_and_linkage/parts/1952

Guys,

I'm still reading and researching stuff here, and I see that Rusty plans to use a 1985-1986 sending unit, and Jacob used a 1995 fuel tank and sending unit.

Does the 1995 EFI tank sending unit have the same inlet and outlet connection sizes? 3/8 and 5/16?

Yes, the later tanks use 3/8” and 5/16” fittings. But they are the quick-disconnect style. And, Dorman sells the connectors for both that use 3/8” nylon tubing, so I bought a 20’ roll and did everything with it.

Oh...I was looking at the Earl's fittings and vapor guard hose...I didn't know you could buy fittings to do it with the nylon hose...hmmmm...very interesting, thanks Gary.

I'm off to go search for Dorman fittings I guess...haha.

Search in Big Blue’s Transformation thread for Dorman. There’re are part numbers, etc.

Rembrant wrote

Rusty_S85 wrote

The fix Holley came up with for correcting the stiff pedal and the sharp break away when trying to lightly apply throttle to leave a red light where it goes from 0% TPS to 50% TPS is the throttle extension lever which is what I bought.  I've installed these in all vehicles with a stiff pedal and it fixed the problem to the point where it feels like you almost dont even have a return spring in most cases due to the extra mechanical advantage it gives you.

Is this the throttle extension that you're talking about?

https://www.holley.com/products/fuel_systems/carburetor_components/brackets_and_linkage/parts/1952

Nope this is it here.

https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_efi_service_components/parts/20-16