Background:
My 96 1.0 3 banger Geo has had several 57 mpg best mpg fills in the last two years. The original 155/80/13s rated at only 35 psi max were swapped out for 195/50/15s that had a 51 psi max. The new tire/rim package was 8 lbs heavier than the old stuff so I removed an extra 32 lbs from the interior so the total wt of the car was still 1630 lbs. I was still getting fuel fills at a best of 57 since the new stuff had lower rolling resistance. Where I used to be able to coast to the next red light now can be done from a longer distance away. I added a grill block and headlight covers but I started to have EGR issues and couldn't get a good mpg reading. I FINALLY ironed everything out but now winter weather and winter gas was here. Spring has sprung and I decided that a MODERNset of the lighter wt 155/80/13s would be the next ticket to better mpg. I got some 44 psi Kumho Powerstar tires in that size and mounted them on 11 lb Primax rims for a total rotating wt reduction of 10 lbs per corner from the 15s...40 lbs removed in just a few minutes. My last four tank fills have netted over 60 mpg with two being63.0!!! The attached link shows the car on the 15s with the aero mods in place.
http://hyperperformance.smugmug.com/...64413387_6htrP
