Cyl head change
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Cyl head change
Newbie here, Recent purchase 1965 f100 step side swb w/300 but it came without a cylinder head. I acquired a head date code = 1985 but rocker towers casting is different. My question; can I use this head with the newer style rocker assemblies? According to RA parts the push rods are the same 1965 thru 1993 as well as the lifters. Thanx in advance for your help!
Jerry (this make truck #5)
Jerry (this make truck #5)
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Joined: Mar 2008
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From: Near Los Angeles
1965? Check the stroke on that engine. You may have a 240.
Right in that time period (85) ford changed the length of their valves. I don't know if the two require diff p.rods. Sounds like you checked. The new head should bolt up w/o issue.
Right in that time period (85) ford changed the length of their valves. I don't know if the two require diff p.rods. Sounds like you checked. The new head should bolt up w/o issue.
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Joined: Dec 2007
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From: Boise, Idaho
Does the '85 head use pedestal rockers? Ie. the rocker arm towers are flat and have a threaded hole. As opposed to the older style that has a pressed in stud that you slide the rocker arm down onto.
If so, it'll work. I put one of these heads on my older 300 and I love it. Much easier to deal with, and from what a few mechanics have told me, it's a superior design. You don't have any chance of studs pulling out, and the forces put on the rocker arms are minimal and don't crack and fatigue the nuts like the older ones.
Checking the stroke of the engine should be easy, especially with the head off. Bring the piston to the top, look where it stops, then rotate the engine until the piston is at its lowest point and measure the difference.
3.18" = 240
3.98" = 300
The head will bolt up to both. Just double check they use the same push rod length (which I believe they do).
If so, it'll work. I put one of these heads on my older 300 and I love it. Much easier to deal with, and from what a few mechanics have told me, it's a superior design. You don't have any chance of studs pulling out, and the forces put on the rocker arms are minimal and don't crack and fatigue the nuts like the older ones.
Checking the stroke of the engine should be easy, especially with the head off. Bring the piston to the top, look where it stops, then rotate the engine until the piston is at its lowest point and measure the difference.
3.18" = 240
3.98" = 300
The head will bolt up to both. Just double check they use the same push rod length (which I believe they do).
Lead Driver
Joined: Mar 2008
Posts: 7,182
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From: Near Los Angeles
I just wanted to clarify: either head style will work, whether you have a 240 or a 300. However, if you put a 300 head on a 240 you will lower your compression ratio about half a point, ie. from, say, 9.0: 1 to 8.5:1.
The 240 head had a smaller combustion chamber that was shaped like a ...what, I guess a kidney bean. Lowering the c.r. might be noticeable in slight power decrease.
The 240 head had a smaller combustion chamber that was shaped like a ...what, I guess a kidney bean. Lowering the c.r. might be noticeable in slight power decrease.
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