horsepower? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

1968CHEVYC10 · 11-30-2009, 06:07 PM

does anybody know what the factory horsepower/torque rating was for the '68 350 with a quadrajet?

**americanmusc1e** · 11-30-2009, 06:58 PM

IIRC, for 1970 it was 255hp net 300hp gross, and 300lb-ft net, 350lb-ft gross,

according to Chevy's sales brochure, but I'm not exactly sure.

but IIRC thought that 350's weren't available until '69, are you sure you don't have a 327???

hugger6933 · 11-30-2009, 07:07 PM

350 was a camaro thing until 69 right? Jim

**americanmusc1e** · 11-30-2009, 08:21 PM

Quote:

Originally Posted by hugger6933

350 was a camaro thing until 69 right? Jim

that's what I was thinkin'!!

Dr. Evil · 11-30-2009, 08:57 PM

Here is a picture of my Brouchure for GMC Truck engines
350 V8 9 to 1 compression

255HP gross at 4600 RPM
195HP net at 4000 RPM
355 # torque gross at 3000 RPM
305 # torque net at 2400 RPM

**americanmusc1e** · 12-01-2009, 11:56 AM

Quote:

Originally Posted by Dr. Evil

Here is a picture of my Brouchure for GMC Truck engines
350 V8 9 to 1 compression

255HP gross at 4600 RPM
195HP net at 4000 RPM
355 # torque gross at 3000 RPM
305 # torque net at 2400 RPM

that, I believe, is what my '70 chevy brochure says, or pretty close to it

1968CHEVYC10 · 12-01-2009, 01:59 AM

Quote:

Originally Posted by americanmusc1e

IIRC, for 1970 it was 255hp net 300hp gross, and 300lb-ft net, 350lb-ft gross,

according to Chevy's sales brochure, but I'm not exactly sure.

but IIRC thought that 350's weren't available until '69, are you sure you don't have a 327???

it's a 350, but its not the original engine so thats probably why. I've not been able to figure out what year it is yet, but I didn't know the 350 wasn't available till '69.
this may be a stupid question but what's the difference between gross and net horsepower?

**americanmusc1e** · 12-01-2009, 11:57 AM

Quote:

Originally Posted by 1968CHEVYC10

it's a 350, but its not the original engine so thats probably why. I've not been able to figure out what year it is yet, but I didn't know the 350 wasn't available till '69.
this may be a stupid question but what's the difference between gross and net horsepower?

there are a couple of sites that will let you decode the casting #'s, that's about the only way to tell without tearing the motor apart. I decoded the casting #'s on our '49 pickup and found out the motor was replaced with a '55 235

dwcsr · 12-01-2009, 03:10 AM

Gross is an ideal HP with minimal accessories and no trans/rear drag. Its the hp at the flywheel under optimal conditions with headers no air cleaner or power draining accessories.

Net is with all the accessories, air cleaner , stock exhaust and is the more realistic of on the road daily driving HP measured at the flywheel.

1968CHEVYC10 · 12-01-2009, 02:19 PM

where's the casting number located on the engine?

**john** · 12-01-2009, 02:52 PM

Heres a couple of helpful sites.
http://www.nastyz28.com/decode.php
http://www.mortec.com/

1968CHEVYC10 · 12-01-2009, 05:02 PM

ok I found the casting number, 3970010, I plugged it in to a couple different site all I could find was it was a 1968 327 or a '69-'79 350, I also found next this next to it, 39GM, I have no idea what that means, any help?

**americanmusc1e** · 12-01-2009, 05:35 PM

Quote:

Originally Posted by 1968CHEVYC10

ok I found the casting number, 3970010, I plugged it in to a couple different site all I could find was it was a 1968 327 or a '69-'79 350, I also found next this next to it, 39GM, I have no idea what that means, any help?

try the heads, sometimes they will help you narrow it down.

1968CHEVYC10 · 12-01-2009, 06:07 PM

you mean the one inside the valve covers?

11-30-2009, 06:07 PM	#1
1968CHEVYC10 Registered User Join Date: Aug 2009 Location: Tomball, TX Posts: 578	horsepower? does anybody know what the factory horsepower/torque rating was for the '68 350 with a quadrajet? __________________ '68 C10 LWB 6.2NA/NP833 3.73's

11-30-2009, 06:58 PM	#2
americanmusc1e Senior Member Join Date: Jan 2009 Location: Austin, TX Posts: 1,079	Re: horsepower? IIRC, for 1970 it was 255hp net 300hp gross, and 300lb-ft net, 350lb-ft gross, according to Chevy's sales brochure, but I'm not exactly sure. but IIRC thought that 350's weren't available until '69, are you sure you don't have a 327??? __________________ -- Josh Instagram: @americanmusc1e OLD SKOOL-- 1970 C10. 454/Th400/3.07 posi Build Thread FARM TRUCK----1949 Chevrolet 3800 Power Wagon Hauler Build Thread 1999 4wd OBS Tahoe - daily. DM me if you can't see photos i posted

11-30-2009, 07:07 PM	#3
hugger6933 Registered User Join Date: Oct 2008 Location: Marianna Arkansas Posts: 7,279	Re: horsepower? 350 was a camaro thing until 69 right? Jim

11-30-2009, 08:57 PM	#5
Dr. Evil Registered User Join Date: Nov 2008 Location: Bernardsville, NJ Posts: 164	Re: horsepower? Here is a picture of my Brouchure for GMC Truck engines 350 V8 9 to 1 compression 255HP gross at 4600 RPM 195HP net at 4000 RPM 355 # torque gross at 3000 RPM 305 # torque net at 2400 RPM Attached Images

12-01-2009, 03:10 AM	#9
dwcsr Hollister Road Co. Join Date: Apr 2005 Location: Houston Posts: 6,134	Re: horsepower? Gross is an ideal HP with minimal accessories and no trans/rear drag. Its the hp at the flywheel under optimal conditions with headers no air cleaner or power draining accessories. Net is with all the accessories, air cleaner , stock exhaust and is the more realistic of on the road daily driving HP measured at the flywheel.

12-01-2009, 02:19 PM	#10
1968CHEVYC10 Registered User Join Date: Aug 2009 Location: Tomball, TX Posts: 578	Re: horsepower? where's the casting number located on the engine? __________________ '68 C10 LWB 6.2NA/NP833 3.73's

12-01-2009, 02:52 PM	#11
john member #16 Join Date: Dec 1999 Location: Yuba City Ca. Posts: 3,618	Re: horsepower? Heres a couple of helpful sites. http://www.nastyz28.com/decode.php http://www.mortec.com/ __________________ john http://67-72chevytrucks.com/vboard/showgroups.php board vendors http://www.flickr.com/photos/1745471...7602865984234/

12-01-2009, 05:02 PM	#12
1968CHEVYC10 Registered User Join Date: Aug 2009 Location: Tomball, TX Posts: 578	Re: horsepower? ok I found the casting number, 3970010, I plugged it in to a couple different site all I could find was it was a 1968 327 or a '69-'79 350, I also found next this next to it, 39GM, I have no idea what that means, any help? __________________ '68 C10 LWB 6.2NA/NP833 3.73's

12-01-2009, 06:07 PM	#14
1968CHEVYC10 Registered User Join Date: Aug 2009 Location: Tomball, TX Posts: 578	Re: horsepower? you mean the one inside the valve covers? __________________ '68 C10 LWB 6.2NA/NP833 3.73's



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.