Curious... MPG for an inline 6????

[72BlckButy]

What kind of MPG do the original inline 6's get? I've seen a lot of threads about increasing MPG in a V8, but I don't recall hearing anything from the inline 6 crowd...

[zeeklu]

My 67 K10 short fleetside 292 with a 4 speed gets around 13 mpg.It has a Holley 390cfm , headers and 373 gears. Chris

[zeeklu]

http://67-72chevytrucks.com/vboard/s...d.php?t=172346 Here's a good post about mpg. Chris

[Palf70Step]

There is typically not a whole lot of difference(maybe 1 or 2 mpg) between the inline 250 and a small block V8with all other factors equal (driving style/tranny/gears)

[68Stepbed]

I remember mine used to get pretty decent mileage. It was better than my 350, but that was probably because I couldn't keep my foot out of the throttle with the new 350

I know my mileage got alot better with the headers though.

[PanelDeland]

I would think that a 6 with headers and a couple other power enhancements with a 3:73 and 700R4 would maybe get 17-18 under ideal conditions.If you are looking for real milage and want to pay top shelf prices,you might go to the 6 from a late model Trailblazer(w/EFI) and auto.Most I have looked at run a 3:42 gear ratio.I think they get around 22-24 MPG.

[68gmsee]

Originally Posted by PanelDeland

If you are looking for real milage and want to pay top shelf prices,you might go to the 6 from a late model Trailblazer(w/EFI) and auto.Most I have looked at run a 3:42 gear ratio.I think they get around 22-24 MPG.

Mine (2006 LS) gets closer to 21-22 on the highway. Not sure if it would require major modifications, but it would be a great little engine for our trucks...

[Willy Prost]

15-17....up to 20 if you drive like you have a live grenade between your foot and the gas pedal and you don't have a death wish.

[AuggieStyle]

Originally Posted by PanelDeland

I would think that a 6 with headers and a couple other power enhancements with a 3:73 and 700R4 would maybe get 17-18 under ideal conditions.If you are looking for real milage and want to pay top shelf prices,you might go to the 6 from a late model Trailblazer(w/EFI) and auto.Most I have looked at run a 3:42 gear ratio.I think they get around 22-24 MPG.

i have been thinking of this since i read your post, with the price of brackets for 6 cylinders A/C AND P/S it would almost make it worth it. i wonder how easily it could be done.

[72BlckButy]

I'm not looking to swap out the SB400, but I've always been curious if they got better gas mileage than a V8.

Now, if my truck had an inline 6 I would definitely keep it in there, because you don't see a lot of them out there anymore.

[lukecp]

I'm sure a Trailblazer 4.2 would get even better mileage in one of our trucks....a Trailblazer weighs around 5000 pounds if I remember right, and our trucks are closer to 4000 pounds or even less. I'm sure the 6 weighs less than a small block V8 too...plus with 270 net horsepower it would have some nice power, quite a bit more than a stock 350.

[jm8872]

My '72 LWB has a 250 inline 6 with granny 4 speed and 4:11 gears and it gets 14 mpgs.

[shifty]

i was lucky to get 10mpg ith my 250 and a single bbl carb. 3.73 gears, 3spd on column, 15" wheels.

[mvfd70]

I had a 68 with a 250 single barrel and 4 speed and I got 10-12. Don't know what rear it had though

[ksjh1316]

My 71 LWB with a 292 granny with 3:73's is lucky to get double digits. She loves to drink gas.

[Brad]

Last summer I used a GPS for 50 miles on a straight and level freeway and calculated that I was getting 17 mpg at a constant 65 mph. That's with wide tires and a tired, high mileage, stock rebuild 250. See my signature below for more specs.