I am hoping to get some advice about what the optimal factory intake could be for a fuel injection project. I am planning out a fuel injection conversion on a mostly stock engine that will be based on the Ford EEC-IV MPFI and MAF fuel injection system. I plan on keeping all modern emissions controls in place, so I need to have provisions for EGR and AIR injection. I hope to use an 80s era cylinder head with the injector ports already in place on the exhaust ports.

I intend to mount the fuel injector bosses in the intake manifold runners near the head pointed at the backs of the intake valves. I also intend to run dual exhaust but with the "tower" on the rear manifold removed to avoid unnecessary intake manifold heat.

Within those parameters, what factory intake would be best? I am assuming the thin walled two piece e-beam welded intakes are a poor choice. What about the thicker single piece cast aluminum intake found on the 80s era trucks and vans? Would those have thick enough walls to drill out and weld in injector bungs? Is there a thermal advantage to aluminum over cast iron? What about from a fabrication standpoint?

I will likely be fabricating the EGR supply tube provisions and I hope to keep the stock attaching point for the EGR valve to the intake.

What do you all think?

I think you're on the right track: 1-piece cast aluminum intake (easier to weld problem-free than iron, also lighter, also provisions for EGR and/or water injection as you choose).

I don't know where the air injection goes on a 300 Ford, whether it's into the exhaust ports or just into the catalytic converter, or both according to an air switching arrangement.

Please keep posting updates about this cool-sounding project!

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Too many people who were born on third base actually believe they've hit a triple.

Will do. As soon as I get some money saved up I am going to get the Ford 300 distributor machined to fit a slant. The next step is the intake machining and fuel rail fabrication.

In the late 80s and early 90s Ford used an AIR injection system very similar to Chrysler's- and air pump with vacuum operated diversion valves directing airflow upstream to the head or exhaust manifolds or downstream to the catalytic. The system was called the Thermactor system and the airflow output was controlled by solenoids controlled by the computer. Adapting this system to the slant would be easy. Use the stock slant air pump and hoses but the vacuum hoses that control the diverter valves get plumbed into the Thermactor solenoids. Easy peasy.

The EGR is also easy to do. The Ford EGR valve is controllec by a solenoid and has a position sensor all monitored by the computer. The 351 I have in my van has the EGR valve plumbed into the intake right behind the throttle body. The EGR gases are supplied by a long tube that bolts to the passenger side exhaust manifold. Since it is a tube it can be adapted to any exhaust system, including a slant!

The real upside to the EEC-IV system is that one can use ANY ecu. It does not have to be the rare 96 CA spec 300 unit.

Oh, interesting. Where's the calibration difference, then?

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Too many people who were born on third base actually believe they've hit a triple.

When using an EEC-IV ECU to control the injection system, one must also use one of the aftermarket "reprogrammers" for the EEC-IV. The EEC-IV was programmed at the factory via an external "port" that the factory would use to flash whatever calibration was intended for the original application. The aftermarket people (i.e. Tweecer, and Quarterhorse, to name two I know of) use this port to attach a separate device that overrides the factory programming and allows the used to substitutes whatever new programming they wish. There are certain limitations, such as the new programming must match the "strategy" of the original ECU (more in depth than needs to be gone into for the purposes of this answer), but using a device such as the Tweecer a user can change all parameters of the engine operation and calibration. Firing order, displacement, timing, number of cylinder, whether or not EGR or AIR emissions systems are present, when the electric fans (!) turn on and off, etc... If it is controlled by the computer, it can be changed.

I do have a 1996 Ford 300 MAF ECU to play with, but I could just as well use a 1989 Mustang 5.0 Federal emissions ECU so long as I used the correct strategy and "tune." This flexibility is why I strongly believe a Ford EC-IV MPFI system is far superior to Megasquist, DIY-EFI, or any of the other bolt-on TBI systems on the market. And I don't think it will cost any more than one of those other systems.

I know the Tweecer has been used to adapt the EEC-IV MPFI system to everything from the mild 351 in my van to dual turbocharged, supercharged engines, from two liter four cylinders to 500+ cubic inch big blocks. t really is that versatile. There is a somewhat steep learning curve when you first start playing with the tuning, but there are some very good websites and mailing lists that support the systems.

A dry intake, true MPFI with MAF metering, fully compliant modern emissions systems, fully controllable and tunable, what's not to like?

Consider epoxy instead of welding the injector bungs.

You can't really aim at the heads of the intake valves because the ports curve so far (110 degrees) that you will just be aiming the injectors as far down the ports as you can. This means having them about 30 degrees from horizontal. Welding the tight side of that 30 degree injector bung will be difficult.

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Good point. Any epoxy brand recommendations?

No real recommendations. I've read of several people having success with good old JB Weld. That's what I used on mine. Time that will tell if that was the right decision.

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--> Check out my FI Turbo build <--
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--> The Diesel Corvette <--

Its kind of pricey but ive been using a 3M product called "Fusor". It is a two part epoxy used in auto body shops for attaching panels where you cant get a welder into. There are different types depending on what you are fusing and the set time you need. I like "108 B" for metal because it gives me a long set time.

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~Nic

Thanks. I guess I will browse the epoxy section at the hardware store. If memory serves, JB Weld sells an epoxy that is supposed to be resistant to gasoline.

But first I need to secure one or two of the one piece cast aluminum intakes. Those 80s slant motors got all the good parts...

If you can get one the. Clifford intake has the bungs cast in. This is what I used, and it has worked well. I used a two step drill to drill the stepped holes for the injectors. I am quite interested in the evolution of this project.

Sam

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The problem with the Clifford intake is that it doesn't have provisions for EGR and I want to keep the EGR system intact and functioning. I might be able to solve that problem by adapting a portion of a 351 upper EFI intake into the throttle body adapter, but that would limit me to using the Ford truck throttle body. The truck throttle body is a two barrel design that has far less aftermarket options as far as air cleaners go, so I would prefer to use the Ford passenger car single barrel throttle body and a factory slant intake.

But I won't be able to make a decision one way or the other until I get to the point of actually starting to try and fabricate things. I do know the large four barrel opening on the Clifford would be much easier to use as far as adapting a throttle body. But since this will be installed in a late A body, hood clearance is also a consideration and the Ford truck intakes are tall.

Plus Clifford intakes are much more expensive that old factory one barrel intakes.

It seems maybe you could adapt the stock mopar EGR to the Clifford intake. I have not taken one out, but it cannot be too complicated.

Sam

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True. However, my plan is to ultimately abandon the factory stock exhaust manifold and run a dual exhaust system (hopefully Dutras) without any provision for heating the intake. In that respect, the Clifford intake would actually be the better choice since I would be fabricating the EGR system anyway. The Ford 351 truck upper intake has an EGR valve immediately downstream of the throttle body and the EGR valve is supplied by an external tube that bolts to the front of the passenger side exhaust manifold. I hope to use that system in my conversion.

However, short term for cost purposes, I will be using the stock slant six intake and exhaust manifolds, at least until I get a running prototype and I can (a) determine if this system can be adapted and (b) get the bugs worked out.

So, long term the Clifford may actually be a better choice. But short term I am trying to keep costs down and keep fabrication to a minimum.