ok..... it's been a few gas fill ups since i posted and i can confirm that lowering my timing does wonders for my gas mileage.... could there be something wrong with my ignition system perhaps?

the thing is..... using a timing light, at 16 degrees at 750rpm, i get 19-24 mpg..... basically crappy gas mileage.....

when lowering the timing to about 14 degrees, it instantly jumps back up to 29-30 mpg and the car feels a lot faster... this is of course with NO other changes....

i tested this for 2 months now..... i would run it at 14 degrees.... 29-30 mpg..... go back to 16 degrees and my gas mileage drops significantly to 19-24mpg....... then just last week i decided to lower it to 14 degrees again and bam... 29 mpg from today's fill up.... my driving varies, but even if i drive like a grandma, i could never hit more than 25mpg with 16 degrees timing.....

??? - i am confused....

oh and i'm using 87 octane btw..... and i have the lower compression b20 which is designed for 87 octane (which is 8.8 or 9.2 compression depending on which b20 theory you believe in)... maybe later i'll test it again at 16 degrees and try 91 octane and see if gas octane is the reason here.....