Anonymous-0

Well-known Member
Thinking about building a really big cubic inch "M" farmall.
I have seen and heard all about the 4.375"X7" making about 120 horses.
But need more, Just how big can you actually build, is 650+ cubes possible or just a dream.
I dont see have you could swing anything bigger then 7'5" and not hit the oil gallery. And when you bore out past the original cast bore it looks like your going to lose all the strength out of the deck and would smash the deck when you tighted the head down. Can you actually weld in a a 4.75 sleeve out of a JD and hard block and get it work?
Just possibly dreaming, but is it possible and still work.
Thanks
 
If I'm not mistaken, Baker builds an 8" billet crank, and somehow turns the block into 5 mains. Not sure how big of sleeves he welds in.
 
5.25 x 8 is my largest ive built. Smaller ones ran better. Bigger is not always better. I dont like anything over 5" bore because you can still run coolant
 
That's almost 700 cubes u sure ain't going to spin it all that fast I've heard of these sized m farmalls out and about but I also they don't hardly last a season if run at real hi elms the other thing I heard that the head can hardly feed that big of cubes correct me if I'm wrong but a friend of mine has engine that was done by Murphys motor service with 7" crank with around 431 cubes runs no higher than 2800 elms and it puts out 150hp and he does very well from 7000 to 9500lb classes running at 4mph in first gear with 18.4×38s
 
I think if run side by side there would be a noticeable difference between the smaller engine making its power with RPM's, and the bigger engine making its power with an extra inch of stroke.

I have purchased from Murphy's before, and his quality is excellent. It would be interesting to see his 431 motor run beside a Baker 436. I just don't see these motors keeping up to one with 100 more cubes.
 
I know he has tried running in 10500 lb class to run against my John Deere 730 diesel and he can't keep up due to his tractor goes to fast and does power out depending on track conditions but he's afraid something will break running that heavy
 
Maybe start with a MD block, crank, and make an aluminum. cyl head for a gasoline conversion. .A real big replica of the 450 lp head to bolt on MD block. Probably squeeze a pretty big bore in a MD block! : )
 

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