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'91 F350 crew cab dually, 351W, and trans options

Hey everyone.
The wife just purchased a truck I have had my eye on for over 15 years, an 1991 F350 Crew Cab Dually "Custom" with an 8 ft bed. Buddy used it to tow his mid 10 sec '69 Mustang GT drag car for years...

It's a project as the 351W is pretty tired, needs bodywork, rear bumper, and whatnot. But it was a KILLER deal. Dang near gave it to us as he didn't use it, and he knows we wont trash or neglect it. The list of "need to do and buy" is already pretty long.

Anyways, to the questions:

1) Being as the EFI is so old, wouldn't there be better ecu options, and an easy EGR garbage(WOW is that a lot of egr pipes, tubes, hoses and valves for port efi!) delete modification? Will be hunting for a late model roller cam 351W to build mildly or buy, but retain the factory intake(and other efi parts). That is, unless there are better options to retain port efi without absurd custom work and expense.

2) as the wife needs to be able to cruise down the highway without winding the windsor to the moon with the 4.11 gears, what options are out there? I have been google'ing possibilities(cop car trans? aftermarket OD?) , but would love to hear other folks opinions and thoughts. Keeping the 351W, no big block or diesel swaps, must stay auto slushbox.

We will never be towing beyond maybe a car and open trailer, no more than 5-6,000 lbs or so, if EVER.

Thanks in advance!

wife's rig.jpg
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Hope you get some hits on this. I've got some EGR questions as well. I come at it from a diesel point of view were EGRs are automatically a bad thing.

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Native Texan
you can just delete the egr on those old motors have done it many of times. worst case is u get a check engine light. but the truck will run and drive fine with out the egr. Or u could spend a couple thousand on an efi kit. Many companies make them and they are coming down in price. comes with everything u need to put efi on a 351w. That was always my plan for my old 67 fairlane. was to build a 351w and efi and replace my 289. But life happen it went so i could keep the 57 and it went so I could stop watching it rot away. now i just have my 95 f350 and 81 horse trailer(toy hauler project).

Give it to Mikey. He won't eat it he hates everything. Hey Mikey!! He Likes It.


Staff member
My 88 is similar in setup. The cat was disabled by a past owner, the air injection pipes rotted off at the valves so capped them, still runs as it always has for years. You could have an overdrive transmission already. 4.10 won't wind real high at highway speeds, but enough if 1:1... My 86 6.9 is 4.10 4 speed...