Hiya peeps! Been a while since I've been on the boards. ...busy w/ last semester of college and all...

Anyway, as a reminder, my ol' 78 F250 (460cid) has been set up for dual-fuel gasoline/propane ever since the early 80's. However, its been run on a strict diet of just propane ever since. As a result, the entire gasoline fuel system, from the tanks to the carb is gonna need to be cleaned/replaced/serviced before it's used again. I'm hoping to do that this summer.

So here's the deal, I'm wanting to take the carb -the original Motorcraft- off to have a go at a rebuild. In the meantime, in order to keep the truck in running condition, I've been trying to find a propane throttle body to mount to the intake; but I'm having the devil's time finding anything marked specifically for Ford (or Motorcraft) 4bbls. --What I AM finding is Holley style throttle bodies.
Now, from what I understand, Ford and Holley were a thing for a while weren't they? I mean, I know some Fords came from the factory w/ Holley carbs, so is there any chance a Holley throttle body will be a direct fit for MY 460 intake?

I ask because I'd really like to find something that didn't require an adapter plate (with the tall 425 mixer and air filter, I suspect space is gonna be tight enough as it is).

I realize most of you out there aren't propane experts (neither am I) and may not have any clue what I'm talking about, but I figure some of you ol...er...wiser guys may be able to point me in the right direction?

i also ran propane in the 80s and loved it as the engine will last forever being such a clean burning fuel with 105 octane to boot the setup i had was straight propane [no duel fuel] edelbrock intake with standard holly flange impco 425 mixer 4" x 14" open element air cleaner and had lots of clearance so you should be able to fit a spread bore to sqare bore adaptor plate and use a holly base plate [600 cfm is fine] and to be honest with you if propane is easy to get where you live/drive i would stay with straight propane and junk the gas system as duel fuel is a compromise at best between the 2
heres the difference
propane already a vapor you can run the engine cooler [160 or so]
gas need heat to turn liquid into vapor droplets [180 or so]
propane higher octane[105] so more timeing/quiker advance possable
gas lower octane peignition if advanced to much
i blocked off the heat risors in the intake,set up the holly base plate so all 4 barrels opened up a the same time right off idle with more power,smoother running and the same milage a few tricks like that and those 460s run nice on that fuel regurds joe

miottimouse said:

with standard holly flange impco 425 mixer 4" x 14" open element air cleaner and had lots of clearance so you should be able to fit a spread bore to sqare bore adaptor plate and use a holly base plate [600 cfm is fine]

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Sweet. Just what I needed to know! And to think, I had just about given up on this post.

Yah, I've been loving the propane so far. This is the strongest, most consistent, and smoothest running all-original 460 I've ever encountered, and I have no doubt it's because of the conversion.
I know running the dual-fuel setup is supposed to compromise it some as far as power/efficiency. So far, that hasn't been an issue- as I've had to do some moderately heavy hauling, and in one case, drag a wrecked Caprice sideways, and the ol' girl hardly even noticed the payload.

Still, I am curious to see what difference a dedicated propane setup would make. In town, it hasn't/wouldn't be an issue, as there's a propane retailer just two miles away. But there's a good chance I'll be moving to Austin (600+ miles away) within the next year or so, so dual-fuel capability will probably be helpful at some point. Hence, my refurbishing the gasoline system.

Thanks again for the help, miottimouse

i have often wondered if the propane was still popular in the usa as in canada its pretty much a dead issue and such a shame as its such a clean burning fuel but as always the oil companys get greedy and up here theres only about .10 differnce between the price of gas and propane and when you consider the milage lost its not worth it we are paying about .80 per ltr
80x 3.8 = $304 a us gal in can $s thats why i went back to gas what are you paying for it your way? sa design also has a book on conversions lots of good info there and i used some of the tricks on my 460 and it ran good also regurds joe

miottimouse said:

80x 3.8 = $304 a us gal in can $s thats why i went back to gas what are you paying for it your way? sa design also has a book on conversions lots of good info there and i used some of the tricks on my 460 and it ran good also regurds joe

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Well, the official price in my neighborhood is $1.87 /gallon of lpg (recently up from $1.65). But the real price is closer to $2.25 or so, once they add in the service charges and stuff. Just had 12 gals put in today and the total was $31&change. Still about a dollar less than the gasoline prices anyway.

I've got one book on conversions already, I'll keep an eye out for the one you're talking about too.