Using a 3.9 in an E150, 1984.

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02-24-2007, 11:16 PM

stormy750

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Using a 3.9 in an E150, 1984.

Normally, using a line-six in a van wouldn't post any problems; the factory air cleaner, although somewhat snug, fits nicely over in a suspension-fashion, the top of the engine.
Enter the need for the "sarcastic" smilie. I decided about six years ago, to swap out the seized 4.9 with another. That brings about an entire other book. Thinking about writing about it. If I do, I'll let y'all know about it and its title.
The reader's digest abridged version - I got sold a 3.9 that not only hadn't seen service in several years, it's previous owner was one of neglect thus never stored it properly. I also find out during the subsequent later rebuild that it'd been over-heated; except for one cylinder, the top ring on each piston was broken.
I'm getting into my book too much. The point of this thread was to detail the six's real size that I rebuilt and what I did to it, in hopes of enhancing its performance. I purchased an Offenhauser intake and split exhaust headers from a wrecker. I was wondering if anyone else had tried this and encountered the following griefs/problems. You should also know that this author lives north of the 49th, where winters are winters and antifreeze is nervous. Here is the list of my headaches:
1.) Due to where the 4-bbl carburator sits, a piece had to be cut out of the metal portion (stationary) of the "dog-house",
2a.) Due to the "new" throat size, the original air cleaner no longer fits. Quite awhile back, I seemed to remember entering a same similar sort of threat, concerning who else had encountered this same problem. However, when I tried to search for this thread, I could no longer find it.
I ended up trying two things; I purchased, designed from and later modified, several times a system made from foil dryer-hose; it was the closest material source that would come close to the throat of the Holley 390 I ended up using, quite by trial and error. During one of the modifications, I designed a dual air cleaner system, one upper and the other to take in air near the exhaust maniford, a task so muchly easier obtained by the factory setup!

More on the "heat thing" later. Another modification was "collar" that bolted onto the top of the throat to which the hose could easily be slid over and clamped. Where I come from the hose clamps don't quite come in the 28" that's required to go around this circumferance; I ended up mating two clamps together, at a suggestion of a farmer who knew exactly what I was trying to do. Sounds simple but there always seemed to be room for error so I ended up using duct tape to ensure no leakage around the point where the collar meets the throat.
2b.) Due to how 2a.) ends up looking and working (poorly, too fragile, high risk of leakage, due to fractures caused by the elements and vibration, I ended up designing an adapter of sorts, from the throat of the 4-bbl to the original air-clearner. It ends up looking so much more like stock

, works more reliably but I am still working the "kinks" out of it; the housing of the adapter, if not designed properly will bind with the choke mechanism, resulting with a poor-starter in cold temperatures because the choke isn't closing properly.
2c.) This poses a problem with regards to the spindle bolt (where the wing nut goes, to hold everything down), which, because the carburator sits about 2" higher then it should, due to a hot water plate that sits between the carb and the Offy, More about this cold weather device in 3.) makes it impossible to screw it into the throat of the Holley then slide the aircleaner over top. You must with one hand, hold the spindle rod loosely between the half-mounted top of the aircleaner and the inside of the carb. Now, the spindle rod is inside of the aircleaner, which now means you can screw it into the throat of the carb before being able to slide the top of the aircleaner over the spindle rod, all the while not being able to see exactly how the spindle rod is lining up with the aircleaner's opening. After doing this a number of times, taking up to two hours per crack, you learn that if you disassemble the filter element of the aircleaner, you fight less with the process and things go together easier.
Remember the thing with the choke binding on the adapter collar. Even if you ensure that it isn't binding before you struggle with the process of the aircleaner, somehow as things "shift" during assembly, the damn mechanism binds.
3.) Cold weather driving usually wasn't too much of an issue with the factory setup. Enter what I've done and you've entered a whole 'nother world of hurt. Complicating issues for me was not being able to find a 4-bbl that would work, right away and ending up using a 2-bbl that I had, that came off of my 351M. The adapter plate was made of such poor metal that, no matter how careful I was with the torque (too much would fracture it too easily) I used, I could NEVER get it to seal. Winter driving was worse; so much air was getting it that not only was starting from a stop an "adventure"

, it would quite often backfire through the carb, often stalling in the most inopportune times, like in rush hour...
I worked on such setups as a shield in front of the carb, to keep the cold air off of it and a cover over the exhaust with a hole in it and the stock pipe from the aircleaner. I designed a manual flapper valve in hopes of directing warm air into the carb. I continued with discovering a "hot-plate" that taps into the heater core system, providing more heat for a device that is reliant upon a certain temperature to run properly at.

Please excuse the length of this dialogue but none of the above is an exaggeration. I bounced back from using the 2bbl to the Holley 390 I bought, which was horribly rebuilt before I got it which made me switch back to the 2-bbl setup which resulted in no end of headaches due to the adapter plate.

Epilogue:

Why haven't I returned to the original factory setup? The 3.9 looked real sweet after it was rebuilt (bored out 20 over), painted and to it, I'd added the Offy intake, freshly painted in Ford engine blue. Add to that picture ( I should add them to my gallery..!) painted-black split manifolds.
Performance-wise, it shone real nice with the Holley 390 and barks a note of authority through chrome lag pipes laid horizontal behind shortened running boards, along with detailed rally wheels. Then, the van's got redone and painted.

That's my story. I'm sticking to it. Feedback?
Jeff
3.9l w. Offenhauser intake, split headers from a 4.9 EFI
Holley 390 4-bbl (presently hurting, unrecoverable - broken outlet post for accelerator pump; looking for same or equivalent)
E150, blue w. van package including rally wheels, personally detailed, shortened running boards, chrome horizontal lag pipes, two additional auxillary core heaters

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