Tire Pressure
Thread Starter
5th Gear
Joined: Sep 2005
Posts: 5
Likes: 0
Tire Pressure
I recently moved from CA to Prescott Valley, AZ. The altitute of my home in CA was about sea-level - maybe
300 feet or so. The altitude in PV in 5100 feet. I have noticed that it takes a considerable amount
of time for the engine to warm up to "normal" operating temperature - approx 5 minutes or so. Also,
when I travel from PV to, say, Phoenix, I start to receive a warning message about tire pressure
being too high - the readings are abou 42 or more lbs. In PV, I don't get these readings - tire
pressure is about 35-8 lbs.
Are these conditions the result of altitude difference between PV and other areas?
300 feet or so. The altitude in PV in 5100 feet. I have noticed that it takes a considerable amount
of time for the engine to warm up to "normal" operating temperature - approx 5 minutes or so. Also,
when I travel from PV to, say, Phoenix, I start to receive a warning message about tire pressure
being too high - the readings are abou 42 or more lbs. In PV, I don't get these readings - tire
pressure is about 35-8 lbs.
Are these conditions the result of altitude difference between PV and other areas?
Instructor
Joined: Oct 2003
Posts: 149
Likes: 1
From: clearwater fl
I found a tire shop that replaces the air in your tires with nitrogen. Nitrogen is a superior tire inflatant because it diffuses throught the tire rubber 30-40% slower than air. As a result, proper tire pressure is maintained for much longer period of time. You will also notice that tire pressure fluctuation is non existent with temperature changes (cold at nights and hot in the days).
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Compressed air is 80 % nitrogen...ALL gasses expand and contract..
while 100 % nitrogen is better than 80 % nitrogen, there is still fluctuation in expansion and contraction under heat and cold... it is about half the rate of compressed air... internal pressure is directly poportional to external pressure...if you have to pay for nitrogen filled tires, it is hardly worth it... Ive seen some plkaces hype the effect and charge 10 dollars a tire..and it just isnt worth it...while nitrogen molicules are much larger than compressed air, it doesnt seep though the tire walls as some would want you to think.... if you have a seal problem and loose some air naturally, nitrogen could help..but that is rare... in hot weather , 95+ days.. tire pressure can fluctuate as much as 7 psi with regular compressed air.... with 100% Nitogen , this will be about half...
The thing you need to do is try to keep your tires around 30/31 psi when they are hot... I have offered these tire tuneup tips for years here on the forum... these results are from years of training and testing... both in the lab and on the NASCAR circuit...
while 100 % nitrogen is better than 80 % nitrogen, there is still fluctuation in expansion and contraction under heat and cold... it is about half the rate of compressed air... internal pressure is directly poportional to external pressure...if you have to pay for nitrogen filled tires, it is hardly worth it... Ive seen some plkaces hype the effect and charge 10 dollars a tire..and it just isnt worth it...while nitrogen molicules are much larger than compressed air, it doesnt seep though the tire walls as some would want you to think.... if you have a seal problem and loose some air naturally, nitrogen could help..but that is rare... in hot weather , 95+ days.. tire pressure can fluctuate as much as 7 psi with regular compressed air.... with 100% Nitogen , this will be about half...
The thing you need to do is try to keep your tires around 30/31 psi when they are hot... I have offered these tire tuneup tips for years here on the forum... these results are from years of training and testing... both in the lab and on the NASCAR circuit...
Last edited by Evil-Twin; May 6, 2006 at 10:16 AM.
Instructor
Joined: Oct 2003
Posts: 149
Likes: 1
From: clearwater fl
Evil, thanks for that info. when i put new tires on all fours (BFG-KDW) the shop had all tires at 36psi. I noticed only about 1/2 psi increase in tire pressure on the highways, but in the summers in florida, it is either hot or hotter. At 36psi the ride is hard, almost comparable to the runflats. would it help if I lower the tire pressure for softer ride?
Former Law Dawg Moderator
Joined: Jan 2005
Posts: 29,434
Likes: 96
From: Eads, Tennessee
CF St. Jude Co-Organizer
St. Jude Donor '05 thru '24
Originally Posted by chanderson
Evil, thanks for that info. when i put new tires on all fours (BFG-KDW) the shop had all tires at 36psi. I noticed only about 1/2 psi increase in tire pressure on the highways, but in the summers in florida, it is either hot or hotter. At 36psi the ride is hard, almost comparable to the runflats. would it help if I lower the tire pressure for softer ride?
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Originally Posted by chanderson
Evil, thanks for that info. when i put new tires on all fours (BFG-KW) the shop had all tires at 36psi. I noticed only about 1/2 psi increase in tire pressure on the highways, but in the summers in florida, it is either hot or hotter. At 36psi the ride is hard, almost comparable to the runflats. would it help if I lower the tire pressure for softer ride?
This a tired a true method used by hundreds of people here on the forum.. tire tuning for conditions is nothing new.. they do it everyday at NASCAR and most other racing organizations. Road surface temps in the summer play a big part in the pressure your tire sees as it roils down the highway. Tire pressure fluctuation can be as high as 7 psi...
