Camaro Power Through the Years

[JR 1]

Interesting graphic GM put out.

[nyrfan]

Seen that on FB, thought is was pretty cool.

[Rocky1974]

Originally Posted by JR 1

Interesting graphic GM put out.

It's interesting, but not very accurate.
GM did build 425 and 430 horsepower Camaros in 1969.
All the 67-70 engines were rated in SAE Gross Horsepower.
Since 1972, all engines have been rated in SAE Net Horsepower.
In 1971 all engines were rated in both SAE Gross and Net Horsepower.
SAE Net ratings give much lower numbers than SAE Gross ratings.
As an example the horsepower rating on Z/28 Camaros went from 330 Gross Horsepower in 1971 to 255 Net Horsepower in 1972, with absolutely no changes to the engine.
The end result of this is that a LS3 Camaro is making more than just 1 horsepower more than a 1969 COPO 427 Camaro, a LOT more.
Today's LS3 would be making around 500 horsepower if it were rated in SAE Gross Horsepower.

[pyroguy]

1969 ZL1 was rated at 430 hp, with realistic numbers being approximately 560 hp. Either way, Chevy is B.S.ing their early numbers.

[Jims73z]

72 z28 was rated at 255 actually.

[JR 1]

Originally Posted by Rocky1974

It's interesting, but not very accurate.
GM did build 425 horsepower Camaros in 1969.
All the 67-70 engines were rated in SAE Gross Horsepower.
Since 1972, all engines have been rated in SAE Net Horsepower.
In 1971 all engines were rated in both SAE Gross and Net Horsepower.
SAE Net ratings give much lower numbers than SAE Gross ratings.
As an example the horsepower rating on Z/28 Camaros went from 330 Gross Horsepower in 1971 to 275 Net Horsepower in 1972, with absolutely no changes to the engine.
The end result of this is that a LS3 Camaro is making more than just 1 horsepower more than a 1969 COPO 427 Camaro, a LOT more.
Today's LS3 would be making around 500 horsepower if it were rated in SAE Gross Horsepower.

True, gross vs. net does skew thing. Some first gen engines were also underrated which confounds things even more. It's still interesting to think about. Today's V6 makes more power than any V8 since the first gen. Granted today's cars are heavier.

[Scalded Dog]

Originally Posted by Rocky1974

It's interesting, but not very accurate.
GM did build 425 horsepower Camaros in 1969.
All the 67-70 engines were rated in SAE Gross Horsepower.
Since 1972, all engines have been rated in SAE Net Horsepower.
In 1971 all engines were rated in both SAE Gross and Net Horsepower.
SAE Net ratings give much lower numbers than SAE Gross ratings.
As an example the horsepower rating on Z/28 Camaros went from 330 Gross Horsepower in 1971 to 275 Net Horsepower in 1972, with absolutely no changes to the engine.
The end result of this is that a LS3 Camaro is making more than just 1 horsepower more than a 1969 COPO 427 Camaro, a LOT more.
Today's LS3 would be making around 500 horsepower if it were rated in SAE Gross Horsepower.

Excellent point... but, to counter that true statement (gross hp was basically measured on an engine with no accessories, while net hp is an engine powering the basics, like oil pump, alternator, whatever the engine will actually be powering in a car), back in the 60s and 70s, manufacturers would often claim a lower hp that the actual engine was making (the engine might make 360 hp, but the manufacturer might claim 325 hp). While this seems really backwards to us who love hp and want more of it, back then, manufacturers were afraid of safety regulators (who might cry "foul!" over cars that were "too powerful," and they did not want to scare customers away, those who might be afraid of increased insurance rates for a car that had a lot of horses to offer.

So... the same engine might produce 300 gross hp, but only 270 NET hp (and, there is no direct mathematical conversion, as there are too many variables in each an every engine setup)... but, in order to "underrate" the hp, the manufacturer might have even reported the gross- 300 hp engine at only 250 hp.

Love the OP's chart... I AM going to take from it the fact that my 1LT makes more horses than ANY Camaro manufactured from 1971 through 1997...

[Scalded Dog]

Looks like JR1 and I had the same thought... he was just a little less wordy!

Good explanation here;

http://ateupwithmotor.com/terms-tech...et-horsepower/

[PalmerGA]

My understanding is that early HP ratings were "at the wheels", where as today's HP ratings are "at the crank". Big difference between 400 HP at the wheels and 400 HP at the crank. (At the wheels is what really matters)

I could be wrong.

[JR 1]

Originally Posted by PalmerGA

My understanding is that early HP ratings were "at the wheels", where as today's HP ratings are "at the crank". Big difference between 400 HP at the wheels and 400 HP at the crank. (At the wheels is what really matters)

I could be wrong.

Both net and gross ratings are at the flywheel. You should read the article Scalded Dog linked to.

[Rocky1974]

Originally Posted by pyroguy

1969 ZL1 was rated at 430 hp, with realistic numbers being approximately 560 hp. Either way, Chevy is B.S.ing their early numbers.

But again, 560 Gross Horsepower would be less than 500 net horsepower.
My point is that when you compare Muscle Car Era horsepower ratings with modern horsepower ratings, you are comparing apples and oranges.

Originally Posted by Jims73z

72 z28 was rated at 255 actually.

Fixed it!

[PalmerGA]

Originally Posted by Rocky1974

My point is that when you compare Muscle Car Era horsepower ratings with modern horsepower ratings, you are comparing apples and oranges.

My point as well. Engine HP is measured differently these days. It sounds impressive to say the 5th gen V6 puts out (virtually) the same HP as the 60s era base 396 V8... but it just ain't so.

[MLAZ1990]

Awesome!!

[Rocky1974]

Originally Posted by PalmerGA

My point as well. Engine HP is measured differently these days. It sounds impressive to say the 5th gen V6 puts out (virtually) the same HP as the 60s era base 396 V8... but it just ain't so.

Oh! It ain't so alright. That V6 in a 5th Gen produces a lot more power than a 60s era base 396. Probably about a 100 horsepower more!

From the article linked above: "A 1967 Chevrolet Impala with the 396 cu. in. (6,488 cc) V8, rated at 325 gross horsepower (242 kW), probably had something like 220 net horsepower (164 kW) in pure stock form."

Let's see: 323-220=103 horsepower more!