Gross vs Net Hp

[bobfist]

Many says the horsepower dropped alot in 73, but they changed the SAE GROSS to SAE NET 1972 and thats a big difference, would a 266 HP 351c 4v 1973 make around 300 if in GROSS ratings then...

Notice that in 72 Ford started with net hp ratings; and between 72 and 73, the 351C 2V went from 8.6:1 to 8.0:1, and lost 9 hp at a .6 point loss of comression, and were rated by the same standard. As you can see, the difference in power between 71 and 72 is 77 hp at a .4 point loss in compression - the biggest difference is in the method that they were rated.

 

[auron73mach1]

In 72 they measured it with all the accessories p/s, a/c, alternator, ect. At least that's what I read.

 

[bobfist]

In 72 they measured it with all the accessories p/s, a/c, alternator, ect. At least that's what I read.

Yes in 72 they started with all accessories on the engines, would be fun to see the SAE Hp on the pre 72 engines,

 

[matrixx]

Id like to see HP ratings from pre 72 that were not botched by ford for any reasons, insurance, safety. etc.

 

[bobfist]

Id like to see HP ratings from pre 72 that were not botched by ford for any reasons, insurance, safety. etc.

Yes, i think the HP in any year isnt correct

 

[bobfist]

Cadillac 500 cui eldorado after dyno SAE NET

Some difference...

Displacement: 8.2 Litres, V-8 (500 CID)

Bore and Stroke: 4.30 x 4.304

Compression Ratio: 8.5 to 1

Gross Horsepower: 365 @ 4400 rpm

SAE Net Horsepower: 235 @ 3800 rpm

Torque: 535 ft.-lbs. @ 2800 rpm

SAE Net Torque: 410 @ 2400 rpm

Carburetor: Rochester Quadrajet 4MV

 

[goodnigh]

My mechanic has a simple solution to the horsepower question.

You back the cars rear bumper to bumper. Attach a chain to both

car's frames and see who pulls who.

I had a 1978 Caddy with 425 rated at 180 HP. That car

weighed 2.5 tons and it was fast!

mike

 

[matrixx]

I think my car would just rip its own bumper off...everytime i bump it rust falls off...haha

 

[bobfist]

Same here:

100hp down 72-73 gross - net , but in real life they where all the same mabey with a difference on 5 hp

440

440-6 Barrel RB V8 in a 1971 Plymouth Barracuda

The 440 was produced from 1966 until 1978, making it the last version of the Chrysler RB block. It had a cast-iron block with iron heads and a bore of 4.32 inches (110 mm), for an overall displacement of 439.7 cu in (7,206 cc).[5]

From 1967 to 1971, the high-performance version was rated at 375 bhp (280 kW) (370 bhp (276 kW) in 1971) at 4700 rpm with a single four-barrel carburetor, and from 1969 to 1971, the highest-output version had a 3-2 bbl. intake setup ("440 Six Pack" for Dodge, "440 6 Barrel" for Plymouth) producing 390 bhp (291 kW) (385 bhp (287 kW) in '71).

In 1972, changes were made to the horsepower ratings of vehicle engines from gross (engine only, without air cleaner, exhaust system, alternator, or other power-consuming components) to net (with alternator, air cleaner, mufflers, and other vehicle equipment installed). The new rating system produced lower, more realistic numbers for any given engine. At the same time, emissions regulations were demanding cleaner exhaust. Engines including the 440 were made with reduced compression, modified cam timing, and other tuning measures to comply with the newly-tightened emissions regulations. The 1972 440 produced 335 bhp (250 kW) (gross) at 4400 rpm; the new net rating was 225 hp (168 kW)—which very closely coincided with period German DIN ratings and TÜV measurements.

The high-output 440 was marketed as the Magnum in Dodges, the Super Commando in Plymouths, and the TNT in Chryslers.

http://en.wikipedia.org/wiki/Chrysler_B_engine

 

[pegasus]

Some interesting reading here on the subject,

http://ateupwithmotor.com/automotive-terms/47-gross-versus-net-horsepower.html

 

[bobfist]

Some interesting reading here on the subject,

http://ateupwithmotor.com/automotive-terms/47-gross-versus-net-horsepower.html

So what i mean, 266 hp Net 1973 is not so bad as many thinks...thats a lot

More than a 396 cui

396 cu. in. (6.4 L) V8, rated at 325 gross horsepower (242 kW), probably had something like 220 net horsepower (164 kW) in pure stock form: decent, but no muscle car.