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homemade87 · 01-14-2012, 01:13 PM

I have an 82 w/ 5.3 & 4l60 swb, everything stock. I did have my local tunner do some work on the pcm. Before I was running a tbi w/ 350 & 200r4. At best I got 12.5. After the swap and running a few tanks . I could tell a lot of diffrence before I even calculated it. I used to get right at 200 miles on a 16gal tank. Now I get about 285 miles on a tank. Now I am close to 18mpg. I have not been at cruise speeds for very long so I dont know what it would do at hwy speed. It may not be much better because of these truck being like a sale in the wind. I am hopeing to get around 20mpg ( wishfull thinking ). But in my case I have about 5.5 more miles for every gal I burn at $3.50 gal ($.086 per mile). That puts me at .47 cents savings for every gal I burn. Keith, you may not see these kind of results because the size and weight of the burb. But I thing you will see some improvement. Good luck with your install. The swap was totaly worth it for me.

Buy the way, I am running a 3.23 gear. With my tire height at 28.3 gives me a 200rpm lower than the stock setup at 60mph.

01-14-2012, 01:13 PM	#14
homemade87 Registered User Join Date: Apr 2010 Location: Guntersville Alabama Posts: 1,073	Re: fuel economy question I have an 82 w/ 5.3 & 4l60 swb, everything stock. I did have my local tunner do some work on the pcm. Before I was running a tbi w/ 350 & 200r4. At best I got 12.5. After the swap and running a few tanks . I could tell a lot of diffrence before I even calculated it. I used to get right at 200 miles on a 16gal tank. Now I get about 285 miles on a tank. Now I am close to 18mpg. I have not been at cruise speeds for very long so I dont know what it would do at hwy speed. It may not be much better because of these truck being like a sale in the wind. I am hopeing to get around 20mpg ( wishfull thinking ). But in my case I have about 5.5 more miles for every gal I burn at $3.50 gal ($.086 per mile). That puts me at .47 cents savings for every gal I burn. Keith, you may not see these kind of results because the size and weight of the burb. But I thing you will see some improvement. Good luck with your install. The swap was totaly worth it for me. Buy the way, I am running a 3.23 gear. With my tire height at 28.3 gives me a 200rpm lower than the stock setup at 60mph.