Tire pressure?

[gid]

Y.S. , he sent me a private message telling me to remove a post I made in one of his THREADS . He wants all the glory . To think these are the people who are MODERATORS and use it as leverage and attack other members with insults . Reminds of a certain ADMINISTARTION for the past 8 years .

[1stToyota]

If over-inflation wasn't ONLY about increased fuel economy, we'd be seeing actual real world test results with handling, braking, etc..., comparing the results of tires that have normal pressure with those with double pressure, not just fuel economy increases, or do the 60p.s.i.ers and the websites they go to consider *safe* being a tire that didn't blow out? I'd like to see some real test results of two cars being track test against each other. I'm betting the car with over-inflated will come in 2nd in every catagory except fuel economy.

[YarisSedan]

Originally Posted by 1stToyota

If over-inflation wasn't ONLY about increased fuel economy, we'd be seeing actual real world test results with handling, braking, etc..., comparing the results of tires that have normal pressure with those with double pressure, not just fuel economy increases, or do the 60p.s.i.ers and the websites they go to consider *safe* being a tire that didn't blow out? I'd like to see some real test results of two cars being track test against each other. I'm betting the car with over-inflated will come in 2nd in every catagory except fuel economy.

http://www.popularmechanics.com/blog...s/4199963.html

[SeaYa]

Originally Posted by 1stToyota

If over-inflation wasn't ONLY about increased fuel economy, we'd be seeing actual real world test results with handling, braking, etc..., comparing the results of tires that have normal pressure with those with double pressure, not just fuel economy increases, or do the 60p.s.i.ers and the websites they go to consider *safe* being a tire that didn't blow out? I'd like to see some real test results of two cars being track test against each other. I'm betting the car with over-inflated will come in 2nd in every catagory except fuel economy.

Thank you! I tried something like this! Snowy parking lot (1-2 inches) and brought my pump. Did 30 psi and 45 psi two times each on a 20 mph turn in the middle of the lot. Here's what happened: 30psi, better traction, worse handling. I slid about 7 feet from my intended line of travel with the car pointed to the outside of the turn. At 45 psi, I had worse traction, but better handling. I slid nearly 12 feet from the intended line of travel, but the car was pointing nearly straight on the way I wanted to go. Did some reading and thinking and maybe this is why: The Yaris is a very light FF, and with an empty trunk, any increases in tire pressure will have a more dramatic effect on the rear tires, eg, smaller contact patch. Since there is already so little weight back there, the rear tires slip to an even greater degree than the front when at 45 psi, hence, the back sliding around more cuts down on the under steer, and you get the feel of better handling. Traction though, another story, I slid 5 extra feet off the 'road', which in straight line braking, could mean running into the hazard you were "looking ahead for and planning for, but still hit because I sacrificed my vehicles engineered performance for an extra 2 MPG"..and by the way, to all the 60psi people...I can't find your actual MPG savings on this post.

To the OP: I've done 35psi (42/44mpg) and 40psi (42/ 47mpg).

Seems to me like the hypermilers are trying to beat the EPA rating by as much as possible for bragging rights. Otherwise, why stop at 60? Why not do 100psi? If your answer is because the tire will burst, then you admit to already pushing the engineered limits of your tire. Otherwise, if traction isn't important to you, why not buy 3 extra spares and run them at 80psi? They're only rated for 60psi, but you don't seem to have a problem with doubling manufacturer recomendations. Let me know how that works out for you.

[1stToyota]

Originally Posted by SeaYa

Thank you! I tried something like this! Snowy parking lot (1-2 inches) and brought my pump. Did 30 psi and 45 psi two times each on a 20 mph turn in the middle of the lot. Here's what happened: 30psi, better traction, worse handling. I slid about 7 feet from my intended line of travel with the car pointed to the outside of the turn. At 45 psi, I had worse traction, but better handling. I slid nearly 12 feet from the intended line of travel, but the car was pointing nearly straight on the way I wanted to go. Did some reading and thinking and maybe this is why: The Yaris is a very light FR, and with an empty trunk, any increases in tire pressure will have a more dramatic effect on the rear tires, eg, smaller contact patch. Since there is already so little weight back there, the rear tires slip to an even greater degree than the front when at 45 psi, hence, the back sliding around more cuts down on the under steer, and you get the feel of better handling. Traction though, another story, I slid 5 extra feet off the 'road', which in straight line braking, could mean running into the hazard you were "looking ahead for and planning for, but still hit because I sacrificed my vehicles engineered performance for an extra 2 MPG"..and by the way, to all the 60psi people...I can't find your actual MPG savings on this post.

To the OP: I've done 35psi (42/44mpg) and 40psi (42/ 47mpg).

Seems to me like the hypermilers are trying to beat the EPA rating by as much as possible for bragging rights. Otherwise, why stop at 60? Why not do 100psi? If your answer is because the tire will burst, then you admit to already pushing the engineered limits of your tire. Otherwise, if traction isn't important to you, why not buy 3 extra spares and run them at 80psi? They're only rated for 60psi, but you don't seem to have a problem with doubling manufacturer recomendations. Let me know how that works out for you.

Good rule of thumb for them is to just throw their gauges away and air the tires up until they resemble motorcycle tires...bet their cars will corner better with a little bit of body-english.

[b_hickman11]

Actually I have a true story about a deer...kind off topic but it shows how deer are in my area. I used to work in a grocery store in high school and I was sacking some groceries on the front end one day. All of a sudden a lady comes runnning in the door screaming bloody murder. She runs towards the back of the store. Well right behind her was a 2 pt buck running into the store also. It ran over to the produce and 2 customers(2 huge guys) tackled it and tied it up. We sold deer corn at the store and kept the bags out on the sidewalk. 2 deer smelt it and came up there to eat it. Then they got spooked and 1 took off back towards the woods. The other one ran towards the door and well you know the rest of the story.

[MadMax]

I don't know why anyone would bother arguing with these "hypermilers," the bottom line is that they are right and the rest of the world is wrong!

I really wonder why these people don't drive a Prius? If they are so dedicated to getting the maximum efficiency out of every drop of gas, then they should select the proper equipment to do so. A Prius with 60+ PSI in it tires and employing those "hypermiler" techniques could get about a bazillion gallons to the mile!

And to my friend in Nacadoches, we both know the dangers of deer in Texas. Maybe we are too stupid not to "plan ahead," or maybe the deer just aren't following the rules! I will ask the next time I see one...

Cheers! M2

[33OH]

I actually used to run 50 psi in my tires just for MPG reasons. And then I hit a deer because I couldn't stop fast enough. Slammed on the brakes and the car just skidded on the road, hardly gripping at all.

Bottom line? I run 32 psi now, what Toyota recommends. Only took $5,000 and the safety of me and my passenger to figure it out.

[MadMax]

ryank, what the hell, didn't you PLAN AHEAD?!?

But I am going to see for myself. I just aired up my tires to 40 PSI (my tire pressure sensor light just went off this morning, so I had to check the pressure anyway) and we'll see how it goes. I sure hope I don't find out the hard way that this is a bad decision...

By the way, what is the PSI level that kicks off the air pressure sensor light? All my tires, sans one, were at 32 PSI; and the one that was a bit lower was only 28 PSI. Seems kinda high for the sensors to kick off...

Cheers! M2

[33OH]

Originally Posted by MadMax

ryank, what the hell, didn't you PLAN AHEAD?!?

Thanks for the laugh

But in all seriousness, if anyone thinks they can avoid an "accident", they're called that for a reason.

[otterhere]

Originally Posted by MadMax

By the way, what is the PSI level that kicks off the air pressure sensor light?

Hmmm; wonder why mine didn't go off? All four tires were at the same LOW level (26) when I finally checked them; with it increased to 38 -- didn't quite go to 40 -- I'm expecting better mileage the next time I check the MPGs...

[nemelek]

ON my wifes CR-V it kicked in at 26 psi. Kind of a good thing. I found a screw in the tire. Without the sensor she might have driven the car until the tire was completely flat.

[YarisSedan]

I dont think it sets the light based on a specific tire pressure but it compares all 4 pressures and when it senses one tire is a amount lower than the rest is when it sets the light.

[b_hickman11]

Originally Posted by YarisSedan

I dont think it sets the light based on a specific tire pressure but it compares all 4 pressures and when it senses one tire is a amount lower than the rest is when it sets the light.

Not true. If it was, your tires could ALL be at 15 psi and the sensor wouldnt go off?!?

[MadMax]

Glad you recognized that as humor, I am sure some people might take it literally! I'm also glad you weren't hurt in that accident, it could have been much worse but I am sure the damage to your beloved Yaris was enough! It would have been for me!

Well, I drove to work with my tires at 40 PSI and I will admit that although it was noticeable, it wasn't that bad. The bumps are a little harsher, but they were already a bit rough with my lower-profile tires. And I don't know if I am getting any better gas mileage going from 32 PSI in my tires to 40; but I keep tab of that info at fill-ups so I will let everyone know my results. I am not going to do anything else different, so I will see how much better the increased tire pressure works.

Stay tuned!

Cheers! M2

[33OH]

From my personal experience, going from 50psi to 32psi, I lost about 2-3 MPG (highway), but the ride is sooo much smoother and the handling (especially in the rain/snow) is 10x better.

[gid]

Originally Posted by ryank

From my personal experience, going from 50psi to 32psi, I lost about 2-3 MPG (highway), but the ride is sooo much smoother and the handling (especially in the rain/snow) is 10x better.

same here with lower p.s.i. , try to keep them hovering around 34 . If you notice harsher ride , car is telling you of the abuse on your suspension as well . Tie rod ends , etc.. Which could / would accelerate the wear on those . Say if part of suspension became damaged under warranty and service center noticed the high tire pressure , they may not honor it . One or few extra m.p.g. not worth it to me .

[smacky]

Wow, I knew a thread about tire pressure wouldn't go well but I'm still surprised. Things have gone downhill since the hack.