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68C15 · 05-18-2010, 10:56 PM

fuel economy is a direct descendant of volumetric efficiency (VE).

VE is achieved many ways but it all comes down to better flow in and out while getting the most use of the air-fuel mix (AF) while in the cylinder.
granted you buddy may have gotten better MPG with the 283 heads and no pinging but you need to look at the whole picture. what cam/lifter set did he have? some will bleed off compression at lower speeds. I had a NICE 355 in an 80 K20 with a crower 00210 cam which bled off the static 11:1 until it hit about 2300. along with a grocery list of other one-off parts and TONS of tuning it netted 17 MPG @ 70 MPH.

IMHO the best way to increase VE is with forced induction (blower etc.).

05-18-2010, 10:56 PM	#18
68C15 blood type; Retumbo Join Date: Jan 2004 Location: next to my reloading bench Posts: 10,269	Re: 283 heads on 350 fuel economy is a direct descendant of volumetric efficiency (VE). VE is achieved many ways but it all comes down to better flow in and out while getting the most use of the air-fuel mix (AF) while in the cylinder. granted you buddy may have gotten better MPG with the 283 heads and no pinging but you need to look at the whole picture. what cam/lifter set did he have? some will bleed off compression at lower speeds. I had a NICE 355 in an 80 K20 with a crower 00210 cam which bled off the static 11:1 until it hit about 2300. along with a grocery list of other one-off parts and TONS of tuning it netted 17 MPG @ 70 MPH. IMHO the best way to increase VE is with forced induction (blower etc.).