1983 Pontiac Bonnewagon, 1979 Pontiac 301, 4 speed Saginaw, 1980 TA 301 Q-jet set to 1979 TA w/301 specs: #70 jets, #44 rods. I was getting some detonation on takeoff, as well as in high gear, for no good reason, driving me bonkers for several years now. Ignition timing was conservative, EGR working. I decided to rebuild the Q-jet and when I opened it, the gas was gone from just yesterday, evaporated away overnight,the bowl was just damp. I found nothing wrong but on a hunch I decided to richen up the primary jets by 3 numbers, to #73 jets, same rods. The change was dramatic. NO detonation, pulls like it grew 2 cylinders, idles better, runs cooler. Now, this set up is even richer than a Pontiac 400 would have normally needed , yet this little 301 eats it up. All I can deduce is that the alcohol in the gas has changed the density of the fuel, requiring a richer mixture for the same power as before. The rate of evaporation is increased, so yeah, after a couple of days, the bowl is dry, answering all those "hard to start" posts. I am amazed.