351CJ & Boss 351 dyno numbers

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"The final small-block in our test was the ’71 Boss 351, which produced an amazing 383 hp at 6,100 rpm and 391 lb-ft at 4,000 rpm. Torque production exceeded 375 lb-ft from 3,300 rpm to 4,700 rpm, showing the big ports and valves on the four-barrel Cleveland heads can be made to work in the lower rev ranges when combined with the right cam and compression."

Obviously they got it all wrong because as we all know 4V heads are no good on the street. :poke:

 
Hemikiller, thanks for posting, education is a good thing. DonC, so true the 4V heads are terrible. So, if anyone wants to give me their CC 4v 351C heads, I'll pay the freight. Chuck

 
"The final small-block in our test was the ’71 Boss 351, which produced an amazing 383 hp at 6,100 rpm and 391 lb-ft at 4,000 rpm. Torque production exceeded 375 lb-ft from 3,300 rpm to 4,700 rpm, showing the big ports and valves on the four-barrel Cleveland heads can be made to work in the lower rev ranges when combined with the right cam and compression."

Obviously they got it all wrong because as we all know 4V heads are no good on the street. :poke:
Yeah, they were so terrible on the street.  lollerz

 
Awesome, from the article:

"Unlike GM, Ford maintained the ’60s-era high compression for one last year and combined the ’70 351 Cobra Jet displacement with the ’69 Boss 302 cam timing. The result was nothing short of amazing, as the ’71 Boss 351 is actually the most powerful small-block Ford or Chevy ever produced."

"With 383 hp, the baddest small-block of the muscle car era was actually produced in 1971." (referring to the Boss 351)

Ford certainly assembled some incredible engines during the classic musclecar era. I find it unfortunate though they just didn't seem to have the market penetration of the other manufacturers with their best offerings. I saw Chevy LT-1 350, 396, Buick/Olds/Pontiac 400 and 455, Mopar 340 and 440 (never saw a live Hemi back then), but only ever saw the more common models of Ford 289, 302, and 351 around back in the day. I know they were out there somewhere, but I never saw people with Boss 351, 428, 429, etc. in Ford musclecars. Those things seemed to be as rare as hen's teeth back then. Just one person's observations...

 
GM was much better at making their high performance engines available in almost everything they made. They were also usually "first to market" with high power engines. Ford was much more conservative in their marketing, both were mistakes in my opinion. If they had made the Ford 427 available in large numbers beginning in 1963 things would had looked much differently. You had to be a bit of a hard head back in the day to be running a Ford/Mercury. In my group of about 40 "street enthusiasts" about 30 were Chevrolets, one Fairlane, my Cyclone, one AMX, one Buick GS, one Dart, and one Charger. Ford didn't "get it" until the middle 80s. You had to embrace the role of the underdog to run a Ford in those days.

 
The people who bad mouth the 4V head have never used them, tried to use a 2.XX rear gear, or installed the wrong cam. Chuck

P.S. I'm still waiting for someone to offer up their free 4V heads  ;)

 
The people who bad mouth the 4V head have never used them, tried to use a 2.XX rear gear, or installed the wrong cam. Chuck

P.S. I'm still waiting for someone to offer up their free 4V heads  ;)
So.......... I hear a lot about Aussie closed chambered heads. How do they compare to Oe ford 4v heads? This should start a conversation?  :chin:

 
Aussie heads are better than most Chevy heads of the era. The magazines love them, because the seem more like a Chevy head, so they understand them. Like anything, you can make them work fine. I think not worth the money. They are no cheaper to buy, cost more to ship from Oz. Valves, springs, seats, machining, cutting for adjustable rockers, studs and guide plates all cost the same.

So for the same money, do you want glorious 4V heads, with all their “problems” that you can rev all day long to 7000 rpm...or some Aussie heads that make your small Ford breathe like a Chevy?

If you found some cheap, and had good flat top pistons laying around, and were afraid of ever revving the engine above 6000 rpm, then they may be for you. They would give you a little more compression than American 2V heads. Your lady friends will not be impressed regardless of the path.

Just to reiterate, they will work fine, a friend had an Aussie headed “fake Boss” I used to race with. This engine was very strong. High rise airgap intake, titanium valves, lots of compression and cam. He ran a super light flywheel and mini clutch with the stacked disks. It was in a 2800 lb 68 fastback. It was a rocket ship. Engine probably cost him close to $20k. Cheaper than my race motor for sure.

 
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