can I improve gas mileage of a 390 ?

[andy2175m4]

Hello all,

I have a 1963 Landau with a 390, that was running an edelbrock 4 bbl carb, when I bought it a year ago. The gas mileage was about 6 - 8 MPG in city traffic, but was 22+ mpg on the freeway.

Due to this terrible city gas mileage, I installed a Holley throttle body 650 cfm 4 bbl injection system, which does a little bit better on gas, but I have not actually measured it yet.

What are the experiences of anyone else out there that has tried to track and improve the MPG of the 390....my 63 thunderbird is my commute car, and I drive it often...(chicks dig it !)

[WVIncagold]

Really the only better way to improve mileage is to lighten the load on the 390. If you replace the heads and intake that will help if they are aluminum as that gets ridd of a couple hundred pounds. You could also try a higher gear ratio or possibly a inline overdrive unit which is costly but it would help. these engines were not designed with fuel economy in mind.

[frame30]

I have had the same idea of trying to make the 390 more efficient, especially given the high cost of Fuel. I was wondering if anyone has put a 302 in to a 1964 Thunderbird with the hopes of (a) using regular fuel and (b) having a more reliable engine. Look forward to your thoughts. Cheers. Michael.