The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - What kind of mpg should I expect after a engine swap?

Plunkett · 08-03-2010, 01:28 AM

Ok, so to start off. My truck is an86 chevy silverado with a 305/700r4 transmssion, 6" lift, 35" tires,and 4.56 gears. I don't ever expect this thing to get amazing fuel mileage. I'm currently looking at twodifferent engine swaps. One being swapping in a gen3 5.3 motor and bolting it up to my 700r4 transmission, the other idea was doing a 350 with a street avenger carb, comp cams 268 cam, and lt headers. I don't drive this truck hard. What kind of fuel mileage can I expect to get from both swaps?

08-03-2010, 01:28 AM	#1
Plunkett Registered User Join Date: Nov 2009 Location: Chattanooga, TN Posts: 140	What kind of mpg should I expect after a engine swap? Ok, so to start off. My truck is an86 chevy silverado with a 305/700r4 transmssion, 6" lift, 35" tires,and 4.56 gears. I don't ever expect this thing to get amazing fuel mileage. I'm currently looking at twodifferent engine swaps. One being swapping in a gen3 5.3 motor and bolting it up to my 700r4 transmission, the other idea was doing a 350 with a street avenger carb, comp cams 268 cam, and lt headers. I don't drive this truck hard. What kind of fuel mileage can I expect to get from both swaps?