sbc vs bbc

[jesse79]

Yea i know this topic sounds like a hear we go again or kust do a search dummy lol
But lets factor everything not just power
For example lets say your running a 1/2 4x4 overdrive tranny 3,73 gears stock wheel size
A sbc would get ya better millage and enof power
Now lets say someone has a 1 ton 4x4 same motor and tranny and gears as above
With a 6" lift and 35s i would assume mpg would be horrible
Now lets put a mild 454 4:10s how much better if any for mpg
We were kinda talking about this at work and kinda thought it would be a fun
Topic to kick around and yes i am bored lol

[BADAZ chevy guy]

I had a 454 in a 73 3/4 ton C20. Empty it got 8-9 MPG. Loaded with a ton (2,050#s) of scrap steel it got 8-9 MPG. Loaded with a full sized over head camper it got 8-9 MPG. I Imagine if I had tried pulling a 3 bedroom house it would have gotten 8-9 MPG. LOL

[jesse79]

Thats sounds about what mine gets and its a 4x2 granted its a crew cab

[Irish_Alley]

my buddy had a 350 in his chevelle. dont know the mpgs but put a 454 and he reported the same mpgs with more power, thats all he changed. the way we saw it was the engine didnt have to work as hard to push the car and waist gas. so that being said my 79 k20 4.10 sm465 38" and 350 could touch 9-10. if i had od i could see her getting 12

[zieg85]

If you keep the engine rpms down on a 454 it'll do decent.  I've gotten just under 16 mpg with mine but kept it around 60.  I shift early and am in 3rd by 35.  I have a 3.21 gear in the rear.  Pulling a car trailer with a full sized truck she dropped to 12.  I have to watch it on wet pavement, it'll break the tires loose if I get on it to fast after I have it in 3rd.  My 85 C30 with the 5.7L TH400 and 4.56 gear will only do 12 

[Stewart G Griffin]

Read this:

http://www.oldsmobility.com/old/carlife_apr67.htm