What is the best way to get 400 hp out of a 351m
Put a 400 HP motor in....
351 Montreal engines are junk, they only last maybe 120,000 miles.
400 HP from a 351M is a tall order. Replace it with a 351C and mod the hell out of it would yield 400+ HP. 351M and 400 Ford engines were never designed to be high horsepower engines due to their low compression. Do some reading at the link below for more info....
I would start with a good set of aftermarket heads like the Edlebrock Performer RPM. A good intake manifold, carb and the appropriate cam (+ rockers etc) along with a good exhaust and ignition system should get you 400 hp. Here is a 400hp crate engine ---- https://www.tristarengines.com/catalog/351w-ford-400- hp-430-torque-street-complete-dyno-d-hp-crate-engine-with-hp- aluminum-cylinder-heads.html
Many parts from the Cleveland engines will work with the 351M. http://www.projectbronco.com/Technical_Articles/Dispelling_the_rum ors.htm
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