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General Discussion => GS Questions => Topic started by: kcombs on August 20, 2021, 06:32:44 PM

Title: Miles per gallon?
Post by: kcombs on August 20, 2021, 06:32:44 PM

How many miles per gallon will a good running 1965 401 GS with a four speed and stock gear get. This is without drag racing or hard acceleration while passing long lines of cars.  :dontknow:

Title: Re: Miles per gallon?
Post by: dsags on August 20, 2021, 06:45:09 PM

15 mpg - on a good day. My experience. In an automatic with 3.08 gears.

10 - 12 with manual and 3.36 gears.

Missed that 4 speed part.

Dan

Title: Re: Miles per gallon?
Post by: Mark Ascher on August 20, 2021, 09:58:03 PM

Dan & Kurt,

Before restoration: 10 mpg.
After restoration: 10 mpg.

Mark

Title: Re: Miles per gallon?
Post by: Rollaround on August 20, 2021, 10:17:02 PM

Uphill           10 mpg
Downhill       10 mpg
Air on           10 mpg
Air off           10mpg

Title: Re: Miles per gallon?
Post by: GS66 on August 21, 2021, 08:43:58 AM

On long trips I have averaged 13-16 mpg. This is with an automatic though.

Title: Re: Miles per gallon?
Post by: vinnie on August 22, 2021, 01:48:47 PM

just returned from a 240 mile trip to Dublin, Ohio and back for the Arthritis Foundation car show. 240 miles round trip, 14.2 gal. of gas =16.9.
Not bad for a 2x4 car. Driving at 65 MPH must of the trip.

Title: Re: Miles per gallon?
Post by: kcombs on September 09, 2021, 02:06:15 AM

Okay, I am going to plan on 15 to 16 mpg on Interstate 5, around town 13. My 1972 F250 with a 460 and a Holly carb gets 10 mpg, I am hoping for better than that. BTW, the truck is the only vehicle I have driven where you can really watch the gas gauge go down. I should have left the original 360 in it, who needs all that power in an old 3/4 ton truck?

Title: Re: Miles per gallon?
Post by: GS66 on September 09, 2021, 11:03:10 AM

 I bet with a TKX 5 speed or automatic with OD 20+ MPG in within reach.

Title: Re: Miles per gallon?
Post by: telriv on September 09, 2021, 08:10:26 PM

The best I've gotten on my '64 Riv. with 425 & 3.08 gears is when I went to the flats of Ken. going to Bowling green. Almost got 20mpg & with a Holley 750 dbl. pumper. Everything being the same but with 3.90's 14-15 even around town.  No better with 3.08's around town.