horsepower rating

The Boss 2 number is actually pretty close to what the modern net hp rating would be, but the peak would be at about 6500, not at 5000 or whatever it was they used in the day for that 290 hp advertised number. No way was that a 400 hp engine, by any measure.

The 290 hp 351C-4v was about 225-250 modern net hp. The '71 Boss 351 was about 350-400. My opinion, based on all the road tests and bench racing, is that the Boss 351 was the quickest production Mustang of them all, at least until the 351W Cobra R and the blown Cobras and Shelbys came along.

180 Out

Something does not add up. I have driven a mid 90's 5.0 Mustang rated at around 250 HP and my '71 351C 4V is a lot more powerful. The car is simply much faster and responsive. Tried to get the car dyno'd but was told if it did not have computer chips or fuel injection, they could not work on it. Bummer.

The numbers don't match the performance. Don't really care if it has 15 HP, it is one Fun ride. Just want to add, the original Cleveland has been B*B'd and modified.

mike

FYI the 93 5.0L rating was 205; it was 215 in 94 and 95; and the 4.6L engine that showed up in 96 also had a 215hp rating. This was upped to

225 in 98 and finally to 260 in 99, where it remained thru 04.

FYI: SAE GROSS(aka Brake) HP figures are calculated without many of the accessories (such as alternator, water pump, exhaust system, etc.)attached to the engine. After the 1972 model year most manufacturers switched to SAE NET HP ratings. The SAE NET HP rating is measured with all accessories installed including a full exhaust system, all pumps, the alternator, the starter, and emissions controls (i.e., engine is tested as it would be if installed in the vehicle).

The following are SAE GROSS horsepower ratings:

1969-70 Boss 302 4V 290 BHP @ 5800 RPM 290 lb-ft @ 4300 RPM 1970 351C 4V 300 BHP @ 5400 RPM 380 lb-ft @ 3400 RPM 1971 351C 4V 285 BHP @ 5400 RPM 370 lb-ft @ 3400 RPM 1971 Boss 351 4V 330 BHP @ 5400 RPM 370 lb-ft @ 4000 RPM 1972 351HO 4V 275 BHP @ 6000 RPM 286 lb-ft @ 3800 RPM 1972-73 351CJ 4V 266 BHP @ 5400 RPM 301 lb-ft @ 3600 RPM

Yet another $.02 worth from a proud owner of a 1970 Mach 1 351C 4V M-code @

Advertised horsepower... ya just gotta love it....

Torques me off.

All the "SCCA's Trans-Am series" cars were 290 horsepower. It was like, who could get more horsepower out of their 290 horse engine.

Al

Bingo!!! For a time, even NASCAR got into some "horsepower wars"... Which manufacturer could build the most ignorant big block and pass it off as "Caspar Milquetoast".

Chevy gave up the venerable 389 and put their money into the 396 (soon to become the 427 and, eventually, 454). Ford went through several permutations of the 427 - tunnel port, high port, SOHC and some other variants thrown in for fun (sexier than the 429) and Dodge redesigned the Hemi (no real relationship to the old 392). The basic requirements were advertised horsepower and homolgation.

Things were getting out of hand and the little teams couldn't buy the big dollar technology.

Today, advertised HP means little.... NASCAR has (IIRC) a 358 inch displacement limit, NHRA is around 600 inches (could be 500 - someone will correct me). What is allowed and what isn't allowed is spelled out pretty tightly.

As far as advertised HP and a street car is concerned.... having a 300 HP car and not having any time slips is rediculous.... Announcing that "My car is advertised at 300 HP" is a lot like putting some rolled up socks in your front pocket.

Street racing is for idiots.....

Well, Chevy was about the best horsepower liar around. Example the 360 and

375 horse 396's. Try to guess how many parts they shared. Only 15 horse difference. Just try:) Another Chevy joke was the 400 and 425 horse 427's. Or the 435 and 430 horse 427's. Whoops, wrong group:)

Al

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