What size motor?
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What size motor?
I bought a 1973 F-250 4x4 about a week ago. The VIN says a 360 but the guy I bought it from said it used to be a 360 and now it's a 390. I set the engine at TDC according to the harmonic balancer then pulled plugs 1 and 7. I then measured from the spark plugs threads to the piston crown in both cylinders. I did it twice and used a cut off piece of measuring tape the first time and the depth probe of a caliper the second time. Both times I got a reading just over 4 inches (with the depth probe I got 1.4 inches in cyl 1 and 5.6 in cyl 7, so 4.2 inches). Does this mean the motor is bigger than a 390 or it is a 390 but I'm just measuring the valve detent in cylinder 7 but not cylinder 1?
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Since a 390 has a 3.78 stroke, getting a 4" measurement might point to either an error in measuring--perhaps the angle or the tape bent or something, or a longer stroke.
The longest aftermarket stroke is 4.25 inches, or a 428 crank is 3.98.
Maybe try a wire or small diameter dowel to get as straight a shot into the cylinder as possible to measure.
That would be great if you have a 445....
Usually, these posts go the other way--"I was told it was a stroker 427 side oiler cross bolted Holman-Moody special" and it turns out to be a 352....
The longest aftermarket stroke is 4.25 inches, or a 428 crank is 3.98.
Maybe try a wire or small diameter dowel to get as straight a shot into the cylinder as possible to measure.
That would be great if you have a 445....
Usually, these posts go the other way--"I was told it was a stroker 427 side oiler cross bolted Holman-Moody special" and it turns out to be a 352....
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Yeah, maybe I should try something a little thinner like a wire. The truck is high enough I could actually pull the pan off without much trouble. Though I don't really feel like scraping pan gasket off the block while the crank is dripping oil on my face........if I were to pull the pan though where would I decode casting numbers? Thanks
*looks like FORDification has 'em. I'll be hoping to find C6ME.........that's a 428 crank. Good luck though right? LOL
*looks like FORDification has 'em. I'll be hoping to find C6ME.........that's a 428 crank. Good luck though right? LOL
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