Go Back   EcoModder Forum > EcoModding > General Efficiency Discussion
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 05-11-2014, 07:06 AM   #11 (permalink)
Tire Geek
 
CapriRacer's Avatar
 
Join Date: May 2008
Location: Let's just say I'm in the US
Posts: 794
Thanks: 4
Thanked 388 Times in 237 Posts
Quote:
Originally Posted by oil pan 4 View Post
.....This will be part of the non road test, fill the tire at night to a set pressure, lay it down on the ground where the sun will hit it, let it get good and hot to simulate being driven and check pressure again. I am not expecting much to happen......
Some things you might not be aware of:

Tires, when first mounted, expand greatly in the first 24 hours - to the point where people who do this regularly add 2 to 3 psi over the target, so that it will be on target after the tire grows.

Second, even tires that have been deflated, then re-inflated suffer from a lesser form of this.

So I'd recommend mounting the tire for 24 hours before starting the test and readjusting the pressure at the start. That reading should be taken in a stable environment - room temperature.

You need to have a sensitive pressure gauge. I think one with tenths of a psi will work.

And lastly, as an end point, you ought to return the tire to its original condition (at room temperature) and check for leakage by measuring the pressure 24 hours after it is returned to that stable environment. THAT reading should be the same as the first one. If not, you have leakage that invalidates the test.

__________________
CapriRacer

Visit my website: www.BarrysTireTech.com
New Content every month!

Last edited by CapriRacer; 06-14-2014 at 08:19 AM..
  Reply With Quote
The Following 2 Users Say Thank You to CapriRacer For This Useful Post:
Daox (06-16-2014), oil pan 4 (12-18-2015)
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 05-11-2014, 03:56 PM   #12 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,175

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,522 Times in 2,796 Posts
Ok these are all tires that are between several years old, to brand new tires mounted on the rim within the last month or so but have seen 0road miles.
My gauge does half psi.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 05-12-2014, 01:32 AM   #13 (permalink)
Eco-ventor
 
jakobnev's Avatar
 
Join Date: Oct 2010
Location: sweden
Posts: 1,630

Princess - '92 Mazda MX-3 GS
House of Tudor
Team Mazda
90 day: 53.54 mpg (US)

Shirubāarō (*´ω`*) - '05 Toyota Prius Executive
Team Toyota
90 day: 54.88 mpg (US)

Blue Thunder - '20 Hyundai IONIQ Trend PHEV
Team Hyundai
Plug-in Hybrids
90 day: 587.16 mpg (US)
Thanks: 74
Thanked 701 Times in 444 Posts
Send a message via MSN to jakobnev
I'm mostly interested in seeing what the tires look like with vacuum in them.
__________________




2016: 128.75L for 1875.00km => 6.87L/100km (34.3MPG US)
2017: 209.14L for 4244.00km => 4.93L/100km (47.7MPG US)
  Reply With Quote
Old 06-13-2014, 11:37 PM   #14 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,175

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,522 Times in 2,796 Posts
I dont try to pull a high vacuum. I figure tires are made to hold pressure in, not the other way around.
I put the air powered vacuum pump on it and let it pull air out till the side walls suck in a little bit.
Then it takes a lot of CO2 to bring them up to 30psig.

So far they have been holding CO2 like a champ.

Next step will be to bleed the CO2 down to 15psig, then bring it up to 40psig with R-404a.

Next time I fill with CO2 I will weigh the bottle before and after.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 06-14-2014, 06:34 PM   #15 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,175

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,522 Times in 2,796 Posts
The CO2 test was on going for a few weeks. About as exciting at watching grass grow.
Tired of that I decided to spice things up a bit.
So I deflated my CO2 test tire from 40psig to 15psig. Then brought them up to 40psig with R-404a.
Then rolled it out in the sun and dropped a sheet of aluminum in front of the tire to act as a reflector to heat the tire up faster. Almost immediately the tire surface temperature jumped up 50°F. The back side of the tire heated up 12°F in about 5 minutes.
This translated to a 2psi pressure rise.
An increase of 5 to 6 degrees F on the shade side of the tire resulted in another 1psi increase. At the same time the sun side temperature had risen another 10°F.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 06-15-2014, 03:53 PM   #16 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,175

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,522 Times in 2,796 Posts
Its looking like with the 50/50 CO2/R-404a mixture I am getting almost a 1psi change for every 10°F in temperature change.

I did a test like this on tires if purged and filled my self with 95% nitrogen back in 2006 and saw something like a 1.5 psi change for every 20°F change.

So the CO2/R-404a mixture only changes pressure with temperature slightly more than nitrogen. Nitrogen according to some people doesn't change pressure as it heats up.

http://ecomodder.com/forum/showthrea...tml#post255838
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.

Last edited by oil pan 4; 06-16-2014 at 02:31 AM..
  Reply With Quote
The Following User Says Thank You to oil pan 4 For This Useful Post:
ecomodded (06-15-2014)
Old 06-16-2014, 02:58 AM   #17 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,175

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,522 Times in 2,796 Posts
Since immediate catastrophic failure has been ruled out it may be time to start limited on road testing, where 1 tire is filled with the mystery gas and the other 3 regular air.
So far my test tires have been with 2 brand new yokohama 30 inch load range C highway tires, that I purged and filled with CO2 and then took one tire forward with the R-404a test. These tires have been on rims and filled with air for a few months before I started messing with their inflation media.

I would also like to know whats going to happen this winter to these tires. Unfortunately I do not have a time machine. But a refrigerator and small trailer tire small enough to fit in said refrigerator should work in place of a time machine.

To be environmental friendly, save the O-zone (*cough* BS *cough*) and be cheap I have set aside an old empty R-134a tank that I can pump down to a vacuum and recover my tire gas. Soon I will have a compressor I can use to pull tire gas out of a tire and force in to a bottle. Then I have more tanks I can store gas in once the compressor is up and running, I dont think these other tanks will survive pulling a vacuum inside them.

The helium biasply trailer tire test will be soon. This test will just be to see how fast it leaks out.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 06-16-2014, 06:15 AM   #18 (permalink)
Tire Geek
 
CapriRacer's Avatar
 
Join Date: May 2008
Location: Let's just say I'm in the US
Posts: 794
Thanks: 4
Thanked 388 Times in 237 Posts
Quote:
Originally Posted by oil pan 4 View Post
Its looking like with the 50/50 CO2/R-404a mixture I am getting almost a 1psi change for every 10°F in temperature change.

I did a test like this on tires if purged and filled my self with 95% nitrogen back in 2006 and saw something like a 1.5 psi change for every 20°F change.

So the CO2/R-404a mixture only changes pressure with temperature slightly more than nitrogen. Nitrogen according to some people doesn't change pressure as it heats up.

http://ecomodder.com/forum/showthrea...tml#post255838
Yes, some folks believe that old wive's tale.

But I disagree about the gases behaving differently.

The Ideal Gas Law predicts a 12°F change for every psi change, and 18°F for 1 1/2 psi. Looks like good correlation there for the data you are getting regardless of the gas. (Keeping in mind you are only able to measure the pressure to 1/2 a psi.)
__________________
CapriRacer

Visit my website: www.BarrysTireTech.com
New Content every month!
  Reply With Quote
Old 06-16-2014, 12:10 PM   #19 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,175

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,522 Times in 2,796 Posts
I believe you are correct.
The Nitrogen tire testing was more controlled.
The gas mix tire was heated by the sun and aluminum reflector.
My difference between the N2 tire test and the gas mix test was about a half PSI difference between the 2, that difference was likely caused by even heating of the N2 tire versus the uneven heating of the gas mix tire.
The gas mix test scope was to heat the tire up as much as possible from the base line to see if there were any wild pressure swings.

I thought there would be a much wider pressure swing with the R-404a mixture, because of the way refigerants act in a refrigeration system.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 06-16-2014, 12:41 PM   #20 (permalink)
EcoModding Apprentice
 
bryn's Avatar
 
Join Date: Jun 2008
Location: trumansburg NY
Posts: 162

sputnik - '93 oldsmobile silhouette
90 day: 23.23 mpg (US)

home sweet home - '92 ford clubwagon E-350 xlt

very excelant - '92 honda civic vx
Thanks: 16
Thanked 10 Times in 10 Posts
[QUOTE=oil pan 4;430103]
My difference between the N2 tire test and the gas mix test was about a half PSI difference between the 2, that difference was likely caused by even heating of the N2 tire versus the uneven heating of the gas mix tire.

you have a pressure gauge accurate to 0.5 psi and you are using a recorded difference of 0.5 psi as significant data?

so... um... well good luck with the research.

__________________
  Reply With Quote
Reply  Post New Thread


Tags
co2 tire filling, cooling mixture

Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com