I am at a crossroad at determining the best fuel injection components for our 1966 galaxie 500 XL and 1966 LTD. It seems there are loads of conflicting information online as well as empirical evidence. So I thought I'd solicit any and all opinions on the matter.

This is what I've researched as well as my own experience with OEM fuel injection systems.

Enter the sticky wicket.

It would appear that all the major fuel injection companies are making multiport manifolds in single plane only. This seems to be a huge source of contention between factions of ideologies. It's not 100% straight forward in the OEM world either which is my reservation.

It's a forgone conclusion that dual plane intakes with carburetors generate more low end torque and better idle and mid throttle response than single plane. The two main reasons from my research seem to be the runner length in a dual plane is more or less equalized and it makes 2 groups of 4 cylinders with each grouping of 4 cylinders every other cylinder in the firing order. This purports to allow evenly spaced pulses to the carburetor which makes it happy. The longer equalized runner length helps with ram air filling the cylinder and at low RPM's helps prevent reversion in the intake spoiling the fuel charge from adjacent cylinders.

And of course a short runner single plane intake has none of this.

Now I can still see how long equal runner length, whether fuel injected or not can help with ram air filling hence why Modular engines, LS engine and Chrysler Hemi V8's have long runners to every cylinder, even though it's multiport injected. Even when GM first came out with TBI in the 80's the V8's had a dual plane intake. I'm guessing GM did loads of research before making countless millions of those engines. Based on these examples it's hard to conclude that a short runner single plane intake is the right choice for multiport.

Enter the exception.

The GM 90's LT1/LT4. So our 1996 Impala SS has sequential multiport however the intakes on those engines are as single plane as single plane gets. The runners are about 3 inches long and that's it. Now the Impy is still a 15 second car, make no reservations, it's also about 500 pounds heavier than our Grand Marquis, which is substantial, it also sports different 1st and 2nd gear ratios in the transmission and a slightly higher rear axle ratio than the Grand Marquis. The Impy's old antiquated push rod 350 small block engine (from 1955) is obviously 1.1 litre's bigger in displacement than the Merc's modern designed over head cam engine that is physically larger than my Mark IV big block Chevrolet 454 engine in my Caprice Classic. However the high mileage Impy is like a bottle rocket compared to the lumbering Mercs (we have two of them a 1994 and 2004 Grand Marquis). The early single OHC 4.6 modular engines developed the same torque as a one legged spider flopping around in a hamster wheel. They are just abysmal.

Obviously it's not a straight forward comparison because of the displacement, weight and gear ratio difference, but the difference in performance is simply staggering. Really all this begs the question of did GM sacrifice some low and mid range torque for more high end horsepower in the LT1/4? Or is the trade off so small it's inconsequential what intake is on there with multiport? This is the 64,000 dollar question.

Can I use a single plane intake on the FE with multiport and will I notice a difference in low end grunt as a result. It's a very expensive question that I've had no luck in determination from research. And of course just because "everyone else uses it or does it" makes me even more leery of it. GM obviously didn't make a horrible mistake with the intake on the LT1/4 engine and putting it into a very heavy B body (body on frame full size car, V8 rear wheel drive) as it's quite zippy for its mass and ancient old engine design and it's really been reliable, well the engine anyway. Then there's the 4.6 intake on the Mercs, I dunno if you ever had one out, but they are massive. Here's my 94 Grand Marquis LS.

The intake consumes most of the valley area of the engine. It has very long runners and a big chamber in the middle. It is literally the opposite of the LT1 intake. I mean just look at that whole engine, it takes up so much room, it's bigger than the Mark IV 454. Bet yet I could pull off 4 spark plug wires off my tired 454 and still do circles around this in a car that is 1000+ pounds heavier than these Grand Marquis's.

Ok enough ribbing on that. Every time I see these Modular V8's it makes me all irritable and rowdy.

So here's my choices for the ancient FE as far as fuel injection is concerned. See what you think, I'd like your opinions please if you will.

I can do a dual plane intake with a TBI:

with this throttle body:

or a multiport setup along these lines:

and

Now ironically because the FE intake is so ridiculously large even the inboard cylinder runners on the single plane intake are pretty long so am I worried for naught?

Now to further add in the debate here is an interesting article about a fella who is also concerned about loosing low end torque to a single plane intake and so he converted a dual plane carbureted intake into a mulitport himself for his 460.

My MPFI Intake Manifold Conversion

He did a nice job too!

Since I'm building both a '66 LTD and a '66 gal 500 XL with the same engine specs, transmission specs and rear end gear ratio I am half tempted to put TBI on one and multiport on the other and run my own comparison. Although I'd really like to have them both the same.

Believe me if I could find an off the shelf dual plane FE intake modified for multiport with rails I already would have bought 2 sets and be on my way to fuel injection. Upon more research and reflection, it would seem GM did hastily use the LT1 in the 93-96 B body cars (Buick also used the smaller varient in their Roadmasters as well Cadillac in their C body). Now the 5.7 litre in the Impala SS not the same engine as used in the Corvettes, Firebirds and Camaros. In fact it's equipped with cast iron heads and a smaller duration camshaft and lift for more low end torque. I'm starting to see the cam and heads were a bandaid for short runner intake in a big heavy car. Another reason why you do not see even the lower grade plebean LS engines with a short runner intake, and a truck LS intake has even longer runners than the passenger car.

On the topic of the Modular engine, the thing that drives me nuts about them is how much time Ford stuck into the design and then for the lowly 2V models they used the worst combustion design (open chamber) and the torque is abysmal at best in their full size car. I realize Ford was backed into a corner from the ever rising corporate fuel mileage set forth by the government, but in all honesty they would have been better off with a 289 or even a straight 6 in the car. At least it would be easier to work on.

Now I will say if you drive my '94 very carefully and by carefully I mean pissing everyone off around you off, I can break 30 MPG on the highway (has the uncommon digital dash option). However if you want to stay with the flow it gets around 22-24. Around town 18-20. However if I tow our little 5 x 8 trailer with it even lightly loaded it plummets to about 12-14. And with say 700 -1000 pounds worth of load it's single digit fuel mileage and can't even break 45 MPH floored climbing hills. It's as if the power band of the engine is so narrow it just barely works in a full size car.

Another reason why I despise these early 2V engines is the aforementioned open chamber design. Whomever programmed the ECU's on these didn't do a good job and at high altitude hot days they detonate like mad, even on the best fuel pump gasoline that's offered to us. Our 2004 Grand Marquis has beat itself to near death as a result. It's making metal in the oil and it makes you cringe when you start it before oil pressure builds. Although once oil pressure is established it's absolutely quiet. That car is relegated for nothing but worst case winter duty. Hopefully we can get at least one more season out of it before the engine throws a rod. If we were to keep it, as there is no rust on the car, there is no way I would replace it with another modular monstrosity, it would most likely end up with a fuel injected 5 litre Windsor out of a Mustang or Explorer.

Hopefully these reasons better explain my irascibility with these engines, especially when we have an older GM full size with higher mileage that gets similar fuel mileage, is much quicker and faster (The old Impy can get to 135 MPH at 6500 feet MSL) and just keeps soldiering on without major driveline problems.

The comparison of the 454 in my Caprice Classic and the Grand Marquis 4.6L was unfair but probably not for the reason one may think. Whilst the Grand Marquis was purposely built for luxury and comfort, so was the Caprice Classic. Ford and Chevrolet were rivals in this market for eons. From the mid 60's to the mid 70's Bel Air/Biscayne competed with Custom 500. The Impala competed with the galaxie 500 and the Caprice/Classic (The Caprice became the Caprice Classic in 1973) vied for market place with the Ford LTD.

It just so happens my 1973 Caprice Classic convertible was special ordered with the 454 in lieu of the base 400 small block it normally came with. However being 1973 when even 460's were struggling to eclipse 250 horsepower mine was a lowly 245 hp. When that lump of sadness was put into a convertible that now weighs in at 4970 pounds without fuel (add 26 gallons to fill the tank and the car is over 5000 pounds), the car originally was slower than molasses trying to move uphill. It barely and I mean barely could spin the tyre on wet leaves. At this point it would be a fair test between the Grand Marquis and my convertible. But all I did to that sad sad 454 was remove the top end and install 1970 LS5 heads and intake as well as an RV towing camshaft and it was night and day difference, at this point it became an unfair test.

In looking at the bigger picture imagine it's 1973, the first oil embargo has taken place, fuel rationing is occurring and some nut-job walks into a Chevrolet dealership and orders one of the largest Chevrolet passenger cars ever produced in a convertible then tops it off with expensive options like air conditioning and then a fuel starving 7.4 litre engine amongst other accessories ticked off on the sheet.

That fella had to be so eccentric, you kind of have to respect it

I suppose that's one reason why I like the car so much the original owner was a whack-job like me.

Rant 1

I swear sometimes I can think myself right into a corner where I'm stuck. The hardest part in research is finding accredited empirical data on esoteric items like new stuff for an old engine like the FE. Some of the comments/reviews about new products I get the feeling are written by shills. That's why I'll consider myself extremely lucky that I can look at another owner's examples of installing the Proflow system and chat with him about results which uses the same intake manifold as one of my possibilities.

About my apprehension for modifying an intake manifold, the drilling seems rather straightforward and my cheesy little mill might even handle it, it's the welding on the aluminum intake I have never done before and it makes me nervous to say the least about experimenting on a brand new 500 dollar intake if you know what I mean. (sigh)

If the single plane EFI intake ends up costing a dozen or so ft/lbs of torque on the lower end I'd be more than OK with that as the 390 I previously put together for the LTD (still sporting a carburetor) will set both brand new rear tyres (I think they're 225) ablaze around 1/2 throttle from a stop. If anything it's a little too much engine for the application, if there is such a thing. The 390 I'm trying to put together for the gal 500 XL is a carbon copy of the 390 in the LTD. In this case I don't mind a little tradeoff.

Rant 2

I don't plan on buying the Edelbrock ProFlow system. The system I'm kicking around the old brain box is an amalgamation of as much as possible OEM style parts. For the control system I am going to integrate the MegaSquirt into the security and convenience package system I'm working on for both cars. But I'd like to choose a system with common OEM components that can be bought at just about any auto part store, such as injectors, fuel pump, fuel pressure regulator, IAC, MAP, TPS, IAT, etc.

That's why I like the Edlebrock EFI FE intake idea (be nice to actually use something with even minimal work such as mild port matching) and use the Holley throttle body assembly atop and load it with appropriate sized injectors. Both Fords have two 3/8" stainless steel fuel lines plumbed from the fuel tank to the engine compartment (did that with the bodies off the frames).

The plan for the fuel pump is to see if I can alter the original sender in the cars to accept a Ford style electric fuel pump. So what I have accrued is a brand new complete Panther fuel pump sender assembly and like the scene from Apollo 13 the goal is to make this fit that, using nothing but this :)~ I'll have to add another line and supports for the pump off the old narrow tiny sender. I have a resistance spot welder, flux and silver solder and a sheet of stainless steel to make the braces. Tricky bit will be getting it into the small tank hole with the float and adding the sealed connections for the motor on the plate.

It would have been nice if Edelbrock added an additional port on the intake cooling jacket for another sensor for the FE. However since I'm incorporating the MegaSquirt into my system I can use the coolant temp sensor voltage to also trigger the "COLD" and "HOT" dash lights appropriately so no need for another hole/sender.

It's all a work in progress, but for the moment it's getting critical to pick an intake manifold and I feel better about choosing the EFI manifold now.

Rant 3

This whole fuel delivery acquisition of information is all meant to not use a carburetor and increase driveability in the summer time. We are 6500 feet MSL. So obviously higher than Denver and the summer time makes for percolation in exterior based fuel bowls like the Holley/Quickfuel. Back in the Midwest, where I'm from, I ran a Holley on another car with no problems year round. My Chevrolet convertible had an ailing Quadrajet for the last 25 years on it and it was getting to the point I needed to either replace it or put a more friendly adjustable carb on there. So I bought a brand new QuickFuel 750 vacuum secondary with electric choke. I spent a weekend with an air/fuel mixture gauge dialing and adjusting the carburetor in the spring time. Below 90 degrees with out the air con running it runs beautifully. Any hotter or run the air con full blast in slow around town driving and the car will stall, hesitate, ect. Remove the air cleaner and the sight glasses on the bowls look like our front loading washing machine during the wash cycle.

There's nothing I can do. It totally went over my head to think about high altitude and heat and cheap fuel, because the Quadrajet never suffered these problems with its tiny centrally located fuel bowl next to both the main and secondary jets that run really cool (Venturi effect and latent heat of evaporation of fuel). So the Quadrajet was actually cooling the fuel in the small bowl, the Holley style carburetor was allowing the blast furnace of heat coming off the engine driven fan to cook the bowls.

It's so bad up here, if you run a chain saw or weedwhacker, they will only start when cool, if you run them, turn them off, they will not start again until they cool down. That's just the rule I guess up here in the mountains.

Regarding the Chevrolet engines having multiple ports for senders, I think it depends on the engine and year. For instance the older Mark IV big blocks had provisions in the intake, the later ones had it in the cylinder head. Not totally sure about the generation of small blocks. I know our '96 Impala SS (gen II small block) has the ECU coolent sensor in the water pump and the gauge sender in the passenger side head.

Rant 4

So my plan currently is to use the MegaSquirt with the autotune package (sold separately). For a distributor I will be using the 1976 FE distributor since it's the only year FE distributor made for Duraspark and has the pick up coil instead of points in it. Plus they make it new. I will remove the vacuum advance, make a cover plate and lock out mechanical advance portion of it. I did notice something interesting in the Edelbrock Pro Flow system as I downloaded the instructions. When they say they have a special distributor designed for their system I automatically ASSumed there was a dual resolution sensor in there; one denoting individual firing pulses per cylinder and a lower resolution one that denoted a single cylinder to fire acting effectively as a camshaft sensor to operate the injectors in sequential mode in lower RPM/Load range.

Upon looking at their diagrams they tie the optional cam sensor input to the dizzy pulse generator, so the Edelbrock system has no idea which cylinder is actually firing. With that I can only conclude the multiport is batch firing, which is a shame really. So on our 1996 Impala SS with the LT1 and OptiSpark distributor there is a high and low resolution optical sensor. The high resolution sensor basically denotes every 2˚ crankshaft movement and the low resolution sensor denotes which cylinder is ready to fire based on uneven and unique pulse widths. I would have thought the Edelbrock system was something similar. As a result even with a mechanical distributor on the LT1 still it's sequential injection and there is no cam sensor.

This gave me the idea of adding either an inductive or capacitive clamp and circuitry to say cylinder #1 high tension lead and with that single pulse per cam rotation MegaSquirt can lock into which cylinder is firing and go sequential for lower RPM/Loads for more precise fuel delivery, much in the same way the Impy's LT1 does it. Like I mentioned earlier the LT1 in the heavy Impy has a 3" intake runner single plane intake and it idles very smooth.

The other thing I noticed about the Edelbrock Pro-Flow kit is there is no apparent provision for a knock sensor to retard timing during a detonation event. That is one thing I do want. With our poor fuel quality (maximum 90 octane) even on hot days with the air con cranked in our Grand Marquis's those 4.6 litre Modular engines ping like mad. Now my 94 Grand Marquis does not have a knock sensor, there is an octane shorting bar in the harness you can change to advance timing for higher octane fuel but it's on the low octane setting and still pings with those awful open chamber Modular engine single cam heads.

The weird part is our 2004 Grand Marquis does have a singular knock sensor in the valley of the Modular engine and it still pings, there are no codes in the ECU and it seems happy, but we've owned that car since it was 4 years old with 40K miles and took stellar care of it and now it's making metal in the oil and it's the mains and or rod bearings as you just cringe when you first start it (mechanically knocking). Weirdly as soon as oil pressure builds (a second or two) it's dead quiet, but it's still making metal and whilst I can't prove it, I would suspect the detonating hammered those bearings to death. The car is now relegated as a poor winter weather car only and hopefully we can get one or two more seasons out of it before it throws a rod. But I digress.

Interestingly the old '96 Impy's control system can detect which cylinder is detonating (dual knock sensors, one on each side of the lower block) and retard individual cylinders even with a mechanical distributor still. As a result that car does not ping even with 87 octane fuel, 10.5:1 static compression, 110˚ F in the city with the air con cranked in city traffic. I'm inclined to mimic well thought out systems like the Impy's, even though it's old by todays standards than some newer (2004) Modular engine control system which clearly is still substandard as it's destroying the engine under certain hot conditions.

Plus in the future I foresee going to electronic overdrive transmissions and the MegaSquirt seemingly communicates with MegaShift and that's a huge benefit to just tie the existing TPS, RPM, and MAP info right into the transmission controller.

Now the tricky bit.... making it all work

Rant 5

I've been doing research on knock sensors and knock phenomena as related to bore size. Very interesting area of study (my cup of tea).

Whilst installing a kit that works is more than tempting, making a very unique thing is inspiring too. I would be lying if I said I wasn't tempted by the Pro Flow kit, but I have some other goals in mind to meet and that bodes towards a custom system with MegaSquirt integrated into the master control system.

Rant 6

I will say that Edelbrock Victor EFI intake is one very large and heavy intake for aluminum. I did order a spattering of different parts to comprise EFI for the FE. I can see some machining work will have to be done to the intake. You get a lot of intake for 800+ dollars but the fit and finish of some areas are bit slap dash.

Rant 7

I thought a picture or two of what I have so far might be in order.

Now there is no MAP on this Holley throttle body so I do have to mount one near by on the intake.

Cheers.

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