There is something wrong with this picture. My 4+1speed, 11/1, hotrod 367, at 3650pounds, has made 30.
If you ask me, there is a conspiracy to sell gas, lots of gas, lots and lots and lots of gas. Somebody is getting really really rich selling lots and lots of gas,, and just maybe, he has the power to put a cap on the mpg numbers. I mean you know, think about it.
Fifty years of technology for 12 mpgs at best, with engines less than half as big.