Several items:

1) At least thru 1979 Ford made a HD version of the 300 six that had a forged steel crank (stnd was cast iron) and heavy duty pistons and valves. Wouldn't this be a great motor to build a hot rod six?

2)The manual also mentioned they added "Positive Stop Rocker Arms Studs" in 1978. I wonder if that is related to my problem with the '77 I once had that always was backing off stud nuts and once the rocker fell off the stud while driving down the highway?

3) I had a custom paint job on my '77 F100 and wondered if someone knows of a place I can send the photograph to get it posted on a web site for all to see?

 

hey, so tell me more on this h-d 6. what manual do you have and how can you tell the difference between a standard and a h-d? I am really interested in these engines and want info. if you know of any good literature please let me know.

 

I first read about it in "Ford Trucks Since 1905," which mentioned the HD in their section on the '65 trucks (I haven't read the rest yet). They didn't say what was HD, though. Browsing a local library I found the '79 Ford truck engine shop manual and that is where I got the info posted above. The '79 manual also says the codes from the engine tag (I don't think this is the same as the VIN tag though), which had the engine ID as the fourth character. Light trucks F and E 100-350 had B for the standard 300 and K for the HD 300 (I think the letters are right, but I will check tonight and let you know for sure). The HD was optional on light trucks in '79, but standard on the F and E 600 thru 900 (oddly coded B). You should be able to check out this manual if you want too, especially if you live in Michigan and have a Michicard library card. Looks like the HD 300 was avail from '65 through at least '79. My '84 manual didn't mention it so I think it was dropped by then. Probably dropped when they quit putting 300s in the really big trucks.

 

While you can do some things with the 300, getting higher revs isn't going to one of those things. The stroke is too long. For your hot rod, look for a 240 for your starting point.

 

Mike: Im not sure I agree that the "stroke is too long" on the 300 six. Remember there are big v8s with long strokes and many hot rodders have stroked their engines. And many folks on this message board have hot rodded 300s. Anyway, back to engine codes: I checked the 79 Ford Truck Shop Manual and it has the following codes for the 300 six:

Light Truck (100-350):B = standard 300
K = optional 300 heavy duty

Medium Truck (600): B = standard 300 heavy duty

Heavy Truck (700-900)
& N600-C600 Panel: G = stnd 300 heavy duty

All these 300s are with one barrel carb.

Now, when I look at the "Chilton Ford Pickups 1965 through 1986" book things get more interesting. According to their table, engine code A was the 240 six and only for '69-'74; then the standard 300 six ran as B from '75-'79, as E from '80-'82 (at which time a 3.8l v6 apparently was the base engine), as Y from '83-'86 (with a "9" in 83 indicating a propane setup). The heavy duty 300 six is only listed for 1979 and is coded K. Since "Ford Trucks Since 1905" notes the HD sic being in the heavy trucks in '65, I assume the HD six was mainly in the heavy trucks and that Ford tired offering it as a option in '79, but apparently dropped that offering after '79, perhaps because few people wanted to spend the extra money. I suppose if you had looked at extra dollars for a HD six, you might have thought the money better spent on a V8.

 

While I am sure there are a number of 300 owners who have modified their engines for performance, the long stroke of both the 250 and 300 is a limiting factor. Both the 200 and 240 have strokes of 3 and 3.2 inches while the 250 and 300 are at 4 inches which isn't favorable to high rpms. For a 'hot rod' engine, stay with a shorter stroke if you want to have a decent engine life.
The V-6 was put into the 1980 re- designed pickups as a way to save some 150 pounds up front over the 300. Ford was trying to sell it as a lighter weight fuel efficient pickup; the lack of popularity by buyers told Ford something else.

 

If the stroke on a 300 is a liability as far as hot rodding this engine, what do you guys think as far as destroking the 300.... combineing internals from a 240 and 300 to come up with a "new" engine? Whats everybodies opinion on this?

 

DUH

 

Just learned a new speed trick the other day from a friend building a 300-6 up.He said that you should use a 240 head on the 300 because i think he said the 240`s have no combustion chambers or something like that.