2023年8月17日 · Initially, two different castings were used: 351Cs with two-barrel carbs had big ports and valves, while 351Cs with four-barrel carbs had huge ports and valves. Two-barrel engines got...

2021年12月2日 · BOSS 351 (1971) and 351C High Output (1972) R-code heads differs from the Early 4V head by having an adjustable valvetrain with screw-in rocker arm studs and guideplates. Late 4V (1972-74) heads have the 351-2V head’s open 74-77cc chambers, 2.190/1.710 inch valves, and port sizing.

2020年10月1日 · The as-cast, production Boss/351C 4V heads flowed a whopping 275 cfm! Combine cylinder head flow with proper cam timing and a decent inductions system, and you have the makings of a serious performer. One need only look at the current crop of modern Coyote, LS/LT and Hemi motors to understand the importance placed on …

2023年1月11日 · With the 4V 351 Cleveland variants, head breathability wasn’t an issue at all thanks to the massive ports and valves. For the high-performance 351C variants, like the M-Code and Boss 351 R-Code engines, an upgraded carburetor and more aggressive cam would likely yield the best results.

2019年1月9日 · The 351C-4V head with its smaller wedge chambers and exceptional quench delivers great mid- to high-rpm performance thanks to huge intake ports that deliver extraordinary breathing.

2006年6月1日 · Four basic types of 351C-4V heads were produced-closed chamber, open chamber, Boss 351, and High Output. Much of it has to do with compression ratio and mechanical lifter use.

First offered in 1970, the 351 Cleveland motor came as a 2V and a 4V engine. The heads and carbs were the difference. The 4 barrel 351 Cleveland had:

2016年8月15日 · A: Starting with the basics, 2V heads are designed for use with a factory 2-barrel carburetor option (2V = 2 venturi), while 4V heads came on one of the five Ford 351C engine configurations that came with a 4-barrel carburetor (4V = 4 venturi). The biggest physical difference between the 2V and 4V Cleveland heads is the huge intake and exhaust ...

It was a low-compression design that included open-chamber "4V" heads, a special intake manifold, special hi-lift long duration hydraulic camshaft, special valve springs and dampers, a 750 CFM 4300-D Motorcraft Carburetor, dual-point distributor, and 4-bolt main bearing caps.

2019年11月18日 · A 351C-4v in a ’67 Mustang would have made a world of difference. Instead, it got the boat-anchor 390, making the sharp 1967 Mustang one of the most disappointing musclecars of the era. Ironically, another Ford V8 that tends to get panned is the Cleveland-type Boss 302, a big-valve, high-rpm, free-breather hampered by its small displacement ...