more air= less traction(not just for going but more importantly for stopping).
= poor ride quality
= no matter what you think......... your tires wear unevenly, just like any tire manufacturer will tell you and i think they would know because of the decades of extensive R&D that they, DOT, and insurance companies have done. as well as independant studies. the list goes on.
You run your 40+ psi, I'll run what Mitsubishi put on my door... 32 front, 29 rear.
To get better gas mileage.... I won't sacrifice safety. I won't.
What do i do?
Well on my 2.0l, 50 trim turbocharged 24 psi, 720cc injector, 255lph fuel pump, with big 8 inch wide tires..........
I lean the closed loop a/f ratio out whiel cruising to 16.5:1 a/f. And i get about 36 mpg.
why don't you just try something like that to get the mileage you want.
Instead of putting yourself and others in danger.