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Theoriginalsilverado 03-23-2014 12:46 PM

Horsepower ratings a lie
 
Hey guys. Just a quick question. I've been told that my 350 cubic inch motor only runs 185 HP. Does anyone have the horsepower ratings for all the engines in our squares? Or do you know what a 350 is rated for? It seems like 185 is a little low

nekkidhillbilly 03-23-2014 01:12 PM

Re: Horsepower ratings a lie
 
about right the ones in 95 only made 200-210 depending on what truck they where in. the vortecs only made 260.

cool68 03-23-2014 01:22 PM

Re: Horsepower ratings a lie
 
what year and model is motor from? any ID numbers? what upgrades on/in motor?

Zane M 03-23-2014 03:01 PM

Re: Horsepower ratings a lie
 
The HP ratings vary across the production run, but basically the 350 was a 165-210 net horsepower motor during the square body era.

If your motor is original and not upgraded/rebuilt, you probably aren't getting the 185 HP at this point either.

mrolds88 03-23-2014 05:39 PM

Re: Horsepower ratings a lie
 
Also after 71 or 72 they changed the way they rated HP. Prior they rated at gross with no accessories, after everything was installed and parasitic losses were factored in.

LONGHAIR 03-23-2014 07:08 PM

Re: Horsepower ratings a lie
 
They have always been "adjusted" to suit the needs of the manifacturers.
They artificially lowered them when they wanted lower insurance rates, so the "gross" figures were not accurate either. The change to "net" figures confused things even more. Then came the emmisions era, where mileage and performance both took a dump. The feds requirments brought mileage back up and fuel injection came along as a way to make that happen.
Modern engines make more power, more smoothly, with smaller displacement, and better mileage.....with worse fuel.

Keith Seymore 03-24-2014 07:15 AM

Re: Horsepower ratings a lie
 
Quote:

Originally Posted by Theoriginalsilverado (Post 6590128)
Hey guys. Just a quick question. I've been told that my 350 cubic inch motor only runs 185 HP. Does anyone have the horsepower ratings for all the engines in our squares? Or do you know what a 350 is rated for? It seems like 185 is a little low

If you have a specific model year in mind I can probably direct you to the actual GM HP and torque curves.

Quote:

Originally Posted by mrolds88 (Post 6590538)
Also after 71 or 72 they changed the way they rated HP. Prior they rated at gross with no accessories, after everything was installed and parasitic losses were factored in.

Correct.

Prior was "gross" horsepower = no accesories, induction or exhaust

SAE testing is now "net" horsepower. Accesory drive in place, as well as engine air induction system and full exhaust.

Quote:

Originally Posted by LONGHAIR (Post 6590686)
They have always been "adjusted" to suit the needs of the manifacturers.
They artificially lowered them when they wanted lower insurance rates, so the "gross" figures were not accurate either. The change to "net" figures confused things even more. Then came the emmisions era, where mileage and performance both took a dump. The feds requirments brought mileage back up and fuel injection came along as a way to make that happen.
Modern engines make more power, more smoothly, with smaller displacement, and better mileage.....with worse fuel.

Also correct.

We used the same 6.2L engine in the H2 as we did in the Escalade.

Escalade = 403 HP - net.

H2 = 383 HP, due to induction and exhaust differences.

K

killthewabbit 03-24-2014 10:41 AM

Re: Horsepower ratings a lie
 
If you have driven a newer v8 car lately, you'll feel the difference. My 85 has a stock 305 that had 165 hp 30 years ago. Driving the wife's 05 Denali with a 6.0 makes mine feel like a rowboat.


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