The next paragraph is background information of why I wanted to compare tires. If you just want to see the test and results, go to the next one.
Concerned that I wasn’t doing something right, or that the terrain in my commute was unusually rough on mileage, I wanted to explore the possibilities that might increase my mileage. My car, a 2000 (#2757) had 32000 miles on it when I bought it. I had posted several times about my mileage or how the rain affects it etc. but now that the weather was warmer I thought I should be getting better mileage. My best tank to date has been 67.9 which I had achieved 3 times. My average consists of mostly interstate driving, but I do a fair bit of around town on the weekends 66mpg for 4,000 miles. Since I was seeing posts of people getting 80s-90s or more, I wanted to increase mine so I could run the A/C this summer and still better my old mileage by at least 3 times. I installed the simplest warm air intake, and use the radiator block when it is cold. Rick Reece lives in Greenville about 30-35 miles away from me and he has been very cooperative in offering advice and stopped by on his commute to show me his car since I had never seen an Insight up close at that time. After talking with him I decided I would get a used one since that was all I could afford. For the most part is has been a great experience for me and I really like the car. Rick has a lot of stuff on his car, and it should be heavier than mine, but gets 20mpg better than I do on the highway. There are other factors like distance of commute, in town driving etc, but I thought I should be able to get better mileage. My car came with an Alpine Stereo, MBQuartz speakers, Sumitomo HTR200 175/65 14 tires and my newest discovery a K&N air filter. It is in perfect condition and it seems to me the person who had it before me had done his homework on the Insight.
I needed to know if I could attain significantly better mileage by going to the OEM tires, or at least enough to recoup my investment in a reasonable time. Rick had graciously accepted my offer of making a controlled (sort of) run and then switching tires to see if there was a significant difference. Our test is far from scientific, but it gave us an idea of the difference between the two (your mileage may vary
). The Sumitomo tires are considered to be low rolling resistance (3rd on the list from greenseal.org).
Rick came over to Spartanburg yesterday and we decided on at least a 20 mile run and I had just received my OBD-2 scanner system, so I could at least verify some information. We did one run and then did a repeat after switching wheels and tires on the cars. I followed him both times, but not very closely as I would fixate on the FCD sometimes, which would probably introduce a fair bit of error. Fortunately he used his cruise and throttle controls.
Track info (from Rick’s gps): 25.7 miles by GPS over rolling hills, Avg. speed by GPS was roughly 55 mph, Min/Max elevation 753/940 ft MSL. Track included 2 stop lights at the turnaround point. Temp 72F first run 76F second run. (“I think the indicated temperatures were a few degrees higher than the real temp as I had the radiator block in thus it probably made the temp warmer than it really was”. (Rick))
My intake air temperature ranged from 109degrees to 113 degrees depending on the engine load. Rick’s was around 146 degrees if I remember correctly. According to the advertised weights for the tires, the Sumitomo’s are only 2 lbs heavier. I didn’t have any scales, so we just compared the two by lifting. The Sumitomo tires felt more than 2 lbs.
Insight #4738 [moderator insert, Rick Reece's](Approximately 150-200 lbs heavier due to full fuel tank, insulation, stereo equipment and heavier driver and floor jack).
Bridgestone tires RE-92 165/65 R-14
Odometer distance 25.9 miles
MPG: 91.6
Max engine load: 94.1% OBDII reading
Max speed: 66.7 mph (GPS)
Avg. Speed 54.7 (GPS and includes turnaround point)
Sumitomo HTR 200 175/65 R14
Odometer distance 25.2 miles
MPG: 78.2
Max engine load: 96.8% OBDII reading
Max speed: 64.3 mph (GPS)
Avg. Speed 53.9 (GPS and includes turnaround point)
Insight #2757 [moderator insert, originalbadbob's](approx ½ tank fuel)
Bridgestone tires RE-92 165/65 R-14
Odometer distance 25.9 miles
MPG: 94.9
Max engine load: 94.7% OBDII reading
Max speed: Approximately the same
Avg. Speed: Approximately the same
Sumitomo HTR 200 175/65 R14
Odometer distance 25.2 miles
MPG: 80.3
Max engine load: 96.9% OBDII reading
Max speed: Approximately the same
Avg. Speed: Approximately the same
My driving impression is that the Sumitomo’s track quite a bit better than the Bridgestone’s, ride better, are quieter and corner significantly better. The IMA was significantly higher with the Sumitomo’s when climbing hills without downshifting, which might make it easier on the batteries in the long run (although I usually downshift on my normal commute). The difference in mileage for our simple test was approximately 15% for both cars. If I was 25 years younger and still sliding around corners, I’d definitely opt for the Sumitomo over the Bridgestone.
For the type of driving I do, I’m going to switch over to the RE92’s as soon as they get here. I ordered a set when I got home. It looks like Roadway Tire in Pompano Beach, FL has the best prices at $47.24 each. Shipping might be more than some other places, but the bottom line is probably better. $223.81 to my door seems pretty good. roadwaywholesaletire.com
Tire Comparison Test
Bob & Rick Reece for your enlightening work.
