36psi Vs. 42psi

[TheManVan]

Well as many of you know simply by upping your tire pressure you can lower your rolling resistance. But some people really never thought about it...
So I had the opportunity to do a before and after fuel economy study on two Honda odysseys. An 2008 lx and a 2002 ex, now since the 2002 ex has VCM its FE is much better.
2008....36psi = 15.7 mpg (driven by three people, who had never heard of Hypermiling)
2002....36psi = 21.7mpg same driving

Then I had the chance to check the tires and I "accidentally" filled them up to 42psi...the max sidewall is 44 so I think that 42 is a safe level.

AND...the results are in..after about 5 fill ups per van the averages are below.
Same driving habits and same exact routes.

2008....42psi = 18.37

2002....42psi = 22.67


And just last week I cleaned the EGR ports and valves on both.. the vans idle about 200-250 rpm lower and run cleaner..so I hope to see even more FE in the next few tanks!
Thanks for the info guys!

[mcrews]

I feel so vindicated........

[mcrews]

actlly Im surprised at the increase given the 36psi startingpoint.
Most are at 32 and go to 44psi.

Very good results though.
no one complained of a harsher ride?

[TheManVan]

No really the ride is firmer when going around corners and the performance over bumps and rough spots seems to be the same!

Yeah I was rather surprised at the increase!

[mcrews]

My last car, Infiniti Q45 Sport had an electronic adjusting suspension. I ran 44psi for 200,000 miles and never noticed.
When I finally sold it I started driving a 2006 KIA Sportage. I increased the psi....wow, did I notice the difference in the ride quality. I got use to it.......but it left me wishing for the Q!!!!!

[Cobb]

You get over the firmerness fairly quickly. I run sidewall psi in all my vehicles. You dont start to notice a smoother ride til you get down to 20 or 15 psi.

Many gen 1 insight owners use 60, 80 to even over 100 psi for the road rallys and mpg races.

[serialk11r]

Damn, that's a big increase. I might have to "accidentally" raise the pressure on my parent's cars and see if it makes as big of a difference. I secretly raised them from the factory 28 or whatever to ~35 already. I have my own car at 36/40 and refuse to pump it higher since the ride is crappy and most of the gas goes to spinning the engine up past 3000rpm thanks to the stupid gearbox.

[ecomodded]

I like 50 psi makes the car roll like mad , its a big jump going from 40psi to 50psi ,its a substantial decrease in rr , it coasts noticeably further/faster, incredible.

[CapriRacer]

Originally Posted by TheManVan

Well as many of you know simply by upping your tire pressure you can lower your rolling resistance. But some people really never thought about it...
So I had the opportunity to do a before and after fuel economy study on two Honda odysseys. An 2008 lx and a 2002 ex, now since the 2002 ex has VCM its FE is much better.
2008....36psi = 15.7 mpg (driven by three people, who had never heard of Hypermiling)
2002....36psi = 21.7mpg same driving

Then I had the chance to check the tires and I "accidentally" filled them up to 42psi...the max sidewall is 44 so I think that 42 is a safe level.

AND...the results are in..after about 5 fill ups per van the averages are below.
Same driving habits and same exact routes.

2008....42psi = 18.37

2002....42psi = 22.79


And just last week I cleaned the EGR ports and valves on both.. the vans idle about 200-250 rpm lower and run cleaner..so I hope to see even more FE in the next few tanks!
Thanks for the info guys!

You should be aware that there have been reports of wet traction and wear issues when using elevated inflation pressures.

And you also ought to compare what you are running to what is stated on the vehicle tire placard - the sticker on the door that lists the original tire size and the vehicle manufacturers inflation specification. What is written on the sidewall as a maximum doesn't imply that it is OK to use for every application. It's a bit more complex than that.

[TheManVan]

Originally Posted by CapriRacer

You should be aware that there have been reports of wet traction and wear issues when using elevated inflation pressures.

And you also ought to compare what you are running to what is stated on the vehicle tire placard - the sticker on the door that lists the original tire size and the vehicle manufacturers inflation specification. What is written on the sidewall as a maximum doesn't imply that it is OK to use for every application. It's a bit more complex than that.

Awe thats no fun! The traction is fine...its a minivan! Not a F1 car! LOL
Nope I have noticed no decrease in traction, both vans have abs and the 2008 has ESA so its not an issue for me or anyone who will ever drive them!
And as for the vehicle placard its a lawyer butt covering sticker....:P
Thanks for you interest in my safety! I need all the help I can get. (I can do stupid stuff) LOL
Thanks for all the great replys guys!