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**First c10** · 05-28-2015, 05:41 PM

The picture below is what I was thinking. Please don't. I know I can't draw lol.

I understand the idea of high velocity in a small pipe with back pressure verse larger size less back pressure and Low velocity. The above chart reads in cfm flow and hp. So single 3" can flow 747cfm and 339 hp. That would say that the 243 heads I have on the motor need to flow 373.5 cfm each. Which I don't think this motor can do NA. The hp number is what has me puzzled. My 08 Duramax has 3.5" after the turbo and before the cat and 4.5 after thru a single muffler (can't remember the brand of the catback system ) motor is 325 hp 600+ torque stock. Probably not the same since it's an oil burner.
I am just thinking it would be different. Maybe put a large nasty chrome tip on it.

05-28-2015, 05:41 PM	#259
First c10 Registered User Join Date: Dec 2012 Location: Los Banos CA Posts: 2,705	Re: Project 68 k10 LWB..aka "The Hulk" The picture below is what I was thinking. Please don't. I know I can't draw lol. I understand the idea of high velocity in a small pipe with back pressure verse larger size less back pressure and Low velocity. The above chart reads in cfm flow and hp. So single 3" can flow 747cfm and 339 hp. That would say that the 243 heads I have on the motor need to flow 373.5 cfm each. Which I don't think this motor can do NA. The hp number is what has me puzzled. My 08 Duramax has 3.5" after the turbo and before the cat and 4.5 after thru a single muffler (can't remember the brand of the catback system ) motor is 325 hp 600+ torque stock. Probably not the same since it's an oil burner. I am just thinking it would be different. Maybe put a large nasty chrome tip on it. Attached Images __________________ 1956 Chevy Bel Air 2 door 1956 Chevy 210 4 Door 1970 K20 LWB project the Hulk build w/Supercharged 4.8L-ly2/4L60E HULK BUILD 1970 C10 Yellow/White Deluxe LWB w/ 5.3L-LC9/6L80E 1968 K10 LWB Dark green my son calls it "THE HULK Jr"HULK JR SOLD GO GO!!!