A local diesel shop was doing a special today in regards to dynoing and I jumped in on it. I actually ended up getting around 8 different dyno's, but they all sucked. My car, which has a 1969 Chevelle 396 engine in it was only pumping out 215 RWHP. I'm not sure how accurate that is, but that number seems really low. I know I can do a few things to increase power, but I doubt I'll do that soon. One thing, though -- I really need a tach. The guys had to use a different method to get the RPMs of my engine.

Anyway, it was an interesting experience. Don't think I've ever seen a car go 95 standing still. The engine is pretty damn loud.

YouTube - 1967 camaro dyno setup

YouTube - 1967 camaro dyno

 

That seems about right. Keep in mind that those old cars didn't put down much horsepower to the rear wheels. I've read an article in Chevy High Performance where they put a 454 LS6 equipped Chevelle on a dyno. It only put down like 285RWHP.

 

I've got a 350 in mine and it only put down 200 HP and 278 Tq. I thought the same about it being low, but it turns out that is about what the 350 was actually rated at, so since most of it was getting to the wheels I was a little less concerned with the low numbers. The LS3 was getting 370ish down on the same dyno for comparison.

 

ok, that makes me feel a little better. The engine IS over 40 years old. What's surprising is how fast the car takes off. I could have sworn it had more power than that. Maybe its the 4.10 gears I have.

 

Back then as today factories rated engine power as measured at the crankshaft using an engine dyno, but engine power was computed differently than today.
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SAE gross power (up to 1972) Cheating & lying common and expected
Prior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower (bhp), frequently referred to as SAE gross horsepower, because it was measured in accord with the protocols defined in SAE standards . SAE gross hp was measured using a stock test engine, running with few belt-driven accessories and sometimes fitted with long tube in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.

SAE NET (After 1972) More truthful, so advertised power is down
In 1971-72, automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net power testing calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer with the power produced by the engine as it is actually configured and sold.

SAE CERTIFIED (After 2005)
In 2005, the SAE introduced "SAE Certified Power". This test is voluntary and is in itself not a separate engine test code but a certification where the manufacturer is allowed to advertise "Certified to SAE J1349" or "Certified to SAE J1995" depending on which test standard have been followed. To attain certification the test must follow the SAE standard in question, take place in a ISO9000/9002 certified facility and be witnessed by an SAE approved third party.
A few manufacturers such as GM, Honda, and Toyota switched to the new ratings immediately, with varying results. The first engine certified under the new program was the 7.0 LS7 used in the 2006 Corvette Z06. Certified power rose slightly from 500 to 505 hp.

 

I'll say this, your car looked damm good on that dyno. Sounded like a beast too. Don't worry about the dyno sheet, just enjoy that beautiful 67.

 

Thanks man.