Griswald- I wouldn't run that much air, personally. That is harder on the suspension, the people that build the car figure those pressures, and of course they want to go as high as reasonanble for better gas mileage. IMO a couple psi over is OK, but running that much air is harder on the suspension, ride, and handling.Based on my 4 years hybrid experience, the more pressure you can run in your tires, the better your mileage will be. My Fusion was in its sweet spot at 44 psi. I haven't started to mess with my Niro tires yet. Some people run as much as 50 psi but that seems to be a bit high to me. They say it still drives OK, though.
Until you've tried it, how do you know how it affects the car? In the Fusion, I couldn't tell any difference until I hit 45 psi. It rode and drove exactly the same except for rising MPG numbers.Griswald- I wouldn't run that much air, personally. That is harder on the suspension, the people that build the car figure those pressures, and of course they want to go as high as reasonanble for better gas mileage. IMO a couple psi over is OK, but running that much air is harder on the suspension, ride, and handling.
I don't need to try something to know of the effect. If you overinflate tires, you get a smaller tread contact area. Less tread on the road. That affects handling. It increases the wear of the center tread over outside tread- so tires wear out quicker. It makes for a harsher ride, the tire is harder- which transmits to suspension, and more road noise.Until you've tried it, how do you know how it affects the car? In the Fusion, I couldn't tell any difference until I hit 45 psi. It rode and drove exactly the same except for rising MPG numbers.
Set mine up to 42 psi yesterday and will report back after a few drives.
I don't need to try something to know of the effect. If you overinflate tires, you get a smaller tread contact area. Less tread on the road. That affects handling. It increases the wear of the center tread over outside tread- so tires wear out quicker. It makes for a harsher ride, the tire is harder- which transmits to suspension, and more road noise.
After 10 fuel fillups with the proper pressures, I am averaging 55MPG. I am very sastisfied with that. I think if I was zealous enough for a small MPG increase to consider overinflation, I would remove the roof rails first. Per EPA ratings, that would be a 1MPG increase.
Sorry, that is crap. The max pressure on the tire is the maximum safe pressure. Above that and you are at higher risk of blow offs and tire damage. The car maker determines what pressure is appropriate for the load placed on the car. That recommended pressure is always in a sweet spot between best efficiency, safety, and tire longevity. You can tinker with it a bit for your road condition and actual load. If you disagree with this, please cite a reputable source and link it.On most vehicles the PSI on the car door is different then what the tire says. Car manufacturers use tire inflation as part of their suspension to cushion the ride. Handling isn't affected until you go over the tire psi spec.
The KIA factory reco of 36 psi (in the book and on the door tag) is based on cold tires and this is also the common spec on all tires. However in Auto racing they play with tire pressures a lot and use different psi for different corners depending on the track layout. I'm huge F1 fan and tires/pressure/composition are huge factors in any given race. BTW, in case you didn't know, they race Hybrids these days !!!Is the maximum inflation pressure for cold tires or the absolute you shouldn't exceed even when the tires are warmed up?
Over the weekend, I drove from Silver Lake to Montrose up the Glendale Freeway portion of the SR-2. At 65mph and with 2 passengers, dash showed 36mpg for that predominantly uphill 11 mile trip. Going back downhill, I decided to take it easy at 60-65mph and the dash showed 87mpg for that 11 miles, haha.I run 42 front, 40 rear, no off roading, so ride is not that much rougher on SoCal freeways. Handles fine, no worries. If I could just flatten SR-2 freeway run uphill, which just sucks the life outta the MPG numbers, I would have 50's also! Although the last fill was 46.1, a personal best! C'est La Vie!!