Mustang MonthlyHow To Engine
Build A Cleveland Powerhouse
Speed-O-Motive's 408 Cleveland stroker kit puts the hammer down for brute horsepower and torque
Photo GalleryView Photo Gallery
The Aussie Connection: PowerHeads
PowerHeads can set you up with Australian 351C heads that are ported and steel seated for optimum performance. The Aussie Cleveland head has the 351C-4V wedge chamber, coupled with "right-sized" ports for great low and midrange torque resulting in good street performance. The 351C-4V chamber offers good quench, coupled with a tight wedge design for reduced detonation. A little bit of work around the intake valves improve flow. PowerHeads works the ports and bowls, which will help your 351C make more horsepower and torque. You can get into these guys for under $1,000.
Cleveland: The Knudsen Connection
We have long accepted the 351C as a small-block Ford, although its weight and size tend to make it more a middle-block--a small-block with larger heads that makes big-block power. However, the 351C's basic architecture says "small-block Ford" with identical bore spacing and size.
Where the 351C block differs is the wraparound iron timing-set compartment, steel timing cover, and a 12/6-o'clock fuel-pump bolt pattern. At first glance, the front of the 351C/351M/400M block resembles the Oldsmobile Rocket V-8s of the era. All had a wraparound timing compartment with a steel cover and 12/6-o'clock fuel-pump bolt pattern.
Here's a loose theory we wish we could confirm. Did Bunkie Knudsen and the engineering people he brought over from GM spearhead the 351C? Semon E. "Bunkie" Knudsen was hired away from GM's Pontiac Division by Henry Ford II in 1967-1968 to run Ford Motor Company. Key events in Ford history were the result of Bunkie's involvement at Ford: the '69-'70 Boss 302 and 429, '71 Boss 351, '69 Talladega/Spoiler II, bolt-on front fascias, and the pucker-mouth '71 Thunderbird and '72 Torino with the Knudsen "Pontiac" nose.
Did Knudsen influence Ford history underhood? Is his influence the reason there were two 351ci engines? We can envision a huge political struggle between Knudsen's people and Ford's people at the time: Knudsen's people for a revised 351ci engine (ultimately called "Cleveland") and Ford's people in favor of staying with the 351W.
When you study the 351C's architecture with its Oldsmobile-like iron block and big-block Chevrolet-like canted-valve heads with huge ports, could Knudsen's influence have been far behind? What's more, take a good look at the 385-series big-block Fords--the 429 and 460. Note the wide canted-valve heads and block design. Then, study the 396/402/427/454ci big-block Chevrolets. Note the similarities in the two designs. Aside from the front-mounted distributor, the Ford big-block is virtually identical to the big Chevy. Can anyone out there help us solve this mystery?