true timing control-REALLY!!!

CRASH said:
In the old days, it was measured as SAE gross. No accesories on the engine.

Now it's measured SAE net, with alternator, PS pump etc.

CRASH


Yeah, that's what I meant. I think. Haha, thx.
 
Just to expand on the SAE Gross vs SAE Net discussion a little. The old rating method was SAE Gross, which basically was the flywheel horsepower of an engine with no accessories OR exhaust system, also the humidity and ambient air temps were much lower. That is why some of the older "muscle" car engines had such high ratings, even though some were still underrated. In the early 70's the industry switched to SAE Net which more accurately measures the power for the engine installed in the car under more common atmospheric conditions. However, these figures are still somewhat misleading because they don't reflect rear wheel output. Even today most HP/torque ratings are for trans tailshaft or are simply "calculated". Very rarely if ever will you see a vehicle's actual rear (or front on fwd) wheel power ratings reported in the specifications for that vehicle, just the "net" figures. It's really all pointless other than it gives you a reference base line to compare to other vehicles. My 2001 4.0, measured in 1969 terms, would probably have listed as 250hp/275ft-lbs rather than the 190/225 in the advertising and maybe 115/150 of actual rear wheel output. It's all very confusing, and largely a concern of marketing.
 
yeah i know in my younger days i had a 1980 olds cutlass that i swap out the 3.8 v6 for a 1970 olds rocket 350 2 barrel stock -with points ignition-and completely spanked a 1990 corvette 3 times-he could not get over it-although i do agree that engines are getting up there now in power i work at a chevy dealer as a tech and i got to tell ya the 05 covette ls2 6.0 liter was fun to test drive!!!!!!!!!!!! :wow:
 
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