lindermant

shroomster,

max cold inflation pressure = 51 PSI

Dunlop SP20 FE
185/70 SR14

http://www.tirerack.com/tires/Spec.j...omCompare1=yes

nick95673

iTrader: (13)

back to the original topic. adding the extra gas wouldnt save you any money. it would just knock your gas mileage down a lil because of the extra weight. i suggest you give your gf your car keys nd tell her to go fill the tank up because you dont like to. trust me this is much cheaper.

joe6680

Just b/c you add a bigger tank doesn't mean you increase fuel efficiency..... In fact I bet you decrease it b/c your just adding weight. So you may go further but your just adding cost.

Jrfish007

iTrader: (3)

Well, yeah, adding more fuel is not more effecient, but the problem is (and I have the same problem) that it is annoying to keep filling the tank. Specially when you have to go out of your way to get to a decent gas station.

drjvic04

...wow. Thats the most intellegent thing I have ever seen on these boards.
You shame me with your wisdom.
You truly are a

HondaLuver

iTrader: (17)

my dads pruis can go 50 mpg, if driven right i can get about 600 miles in a non stop trip

CivicSF

here's a much better solution:

http://www.nationalfuelsaver.com

aftermarket canister that you T right into your vacuum line, platinum vapors mixed into the intake supposedly increases combusion cycle by 22% thermal effeciency

did some math after talking with dude to see if it was worth the money invested:

** $199 per NationalFuelSaver package for 7th gen civic
** 30,000 miles worth of product per canister, then need refill (cost unknown)
** 30,000 stock mileage x 122% improved mileage = 36600 miles
** cost of 6600 stock miles in gas:
6600 / 35 mpg (conservative): 188.57 gallons
188.57 x $2.75/gal (adjust as neccesary): $518.57
** $518.57 gas savings - $199.00 product price = $319.57 real world savings

with the assumption the product works as indicated, i've just ordered mine can't talk from experience, this should put $319.57 in your pocket per canister in the long run. i'll post when i get real data.

CivicSF

upping the tire pressure isn't a good way to attain better gas mileage. you sacrafice considerable ride quality, cornering ability, and you're at high risk for fun tire adventures i.e. riding home on a spare. tires are designed for optimal pressures, follow specs recommended from the manufacturer spec (+/- a few psi is always necessary for variables)

if someone is getting great gas mileage ten buck says it has to do with driving, conditions, and many other things rather than tire psi

Jrfish007

iTrader: (3)

hahaha..... here is the trick to that, just because you have 22% more thermal effeciency doesn't mean you have 22% more MPG. If you really want I can break down how thermal effeciency is defined and why that does not mean an direct increase in the Otto cycle, or you can take my word for it as an engineer that knows WAY to much about thermodynacis, you will be lucky to see a 10% increase in milage with a 22% increase in thermal effeciency.

Jrfish007

iTrader: (3)

I don't think anyone here said they where driving with their tire out of spec, like I said my truck tire say right on them they can go up to 65 psi cold. Yes all that stuff does get worse, but appartently they still think it is safe :shurg:

shroomster

max p.s.i. is referring to the max p.s.i the tire can be pressurized at while holding the maximum load (for example a tire has a max p.s.i of 44 and a max load range of 675 lbs. which means at 44 p.s.i if the load range exceeds 675 lbs the tire can/will fail) its simple math to find an optimal operating pressure, cept I feel if you want to drive on bricks drive on bricks who is to tell you how to air your tires....

ncirom2003

iTrader: (7)

shroomster is 100% correct here.
as for tires, everyone just put them to spec that is in the door jamb. if a couple miles per tank more is worth it to you, go on a diet and put it in neutral when your going down hills.

oh yea and REMEMBER THIS!....... if your manufacturer recommends 32psi that is when the tire is cold say in the morning. if youve been driving for a little while, lets say long enough for the engine to heat up, then add 5psi. so if you check your tire pressure at a local gas station after driving or on a trip, you should put it to 37psi. and if its really really cold (say an icy winter morning) i guess maybe you should put it to 30psi rather than 32, but im not sure on that one.

just read about that 22% dealy real quick. to me thinking about how a cars computer system works and all i dont see how a more complete combustion would cause the computer to inject less fuel to save gas. however it sounds like it could help maximize hp output. after all more gas burning means more power. but what if the platinum it injects lowers the fuels heating value, i know gasoline has a btu per gallon rating of about 215,000. so what if the platinum being injected lowers this, which it will just as if you inject ethanol with gas it lowers the heating value. so i guesss thats also something to think about. maybe its not doint what they say..............

Jrfish007

iTrader: (3)

Yes, well I'm refering to my Ford, which see lots of heavy loads and off roading (it's a real work truck), and given that Ford's are known to flip because of tires bolowing out due to to low of tire pressure, I think I'll put a little extra pressure in it But my '06 Civic runs at 32 ish because the most load it sees is 2 people, same with my Integra.

nick95673

iTrader: (13)

it was a tire compound problem. the stock tires would nearly melt in the summer heat. thats why customers in south america and the tropics were experiencing the problem b4 those in the northern hemisphere. run your tires at recomended psi.

Jrfish007

iTrader: (3)

It was a compound problem in the sidewalls that under low pressure the adhesion of the polymer would termintate if under to high of sheer pressure. The guy next to at work was working at Firestone when that happened, he watched the team that found that particular flaw and what caused it. It was a catalyst supplier problem in the end, bad catalyst = bad product.

Those people in the south where doing a lot of off roading, it is common practice to deflate the tires for off roading to increase the abilty to grip, the tire "forms" around the rocks and such. I have a friend with "swampers" on his jeep, he runs that at 4 psi. It is fiine if you are not traveling at high speeds, the problem was that they would deflate their tires for off road, then drive on the paved roads at high speeds with the low tire pressure.

The real problem was that salesmen would tell people to lower the tire pressure if they wanted a better ride, I was told this at one point too. Think of a flat tire and how the tire buldges at the bottom. If you rotate that tire like that a 1,000 times a minute, that is alot of flexing for the side wall, eventually that causes heat (heat of deformation) that heat accumlates and eventually will melt and weaken the polymer structure causing a blow out. It makes sence that higher temperature climates would blow out first because the ambient temperature is higher, so it does not require as much heat to deform.

The tire was fine when properly inflated, both Ford and Firestone said this. But if the valve stem devolped a leak (or someother way pressure was lost) and the driver did not notice (which is quite common), a blow out could occur, and this is why they where recalled.

If the tire was a little over inflated, there would be little to no problems with that specific tire. As I said earlier, I run my tires according to what the tire says and am aware that under heavier loads the tire needs to be inflated to a max of 65 psi, so when hualing something, I make sure the cold tire psi is not above the stated pressure

shroomster

<<<JRFISH

I just wish a shop around here had nitrogen.... my front dr. tire always loses about 6 p.s.i a month...I gotta stay away from the Taco Bell....

ncirom2003

iTrader: (7)

good to know, i didnt know it was a problem that the adhesion broke down under heat. i thought it was just not adhered properly and would rip off under stressful situations. stupid blue oval! oh and people are kinda dumb to drive around with such low tire pressure thinking nothings wrong (talkin about off road hobbiests)
oh and im willing to bet another cause for this was people inflating the tire while it was hot and not compensating for the extra pressure needed. i see people do this allllll the damn time.

Jrfish007

iTrader: (3)

Well part of the problam is that Ford prides them self on having the smoothest riding truck. As every body knows the tire plays a huge roll in that, if the side wall is somewhat flexible and soft it will give more when you hit a bump and create a smoother ride. The bad thing is, to make it more flexible, you weaken the strength of the polymer (i.e. use longer polymer chains with less adhesion), so it will break down faster than it should.

So yeah, Ford was just tring to keep their trucks smooth by having Firestone make a soft side wall on the tire. It was fine and dandy until Firestone's supplier made a slight change in the polymer catalyst, which then made slight change in the polymer (made it a little weaker), which then caused these problems while the tire was under inflated.

On a side note, Ford is now pushing for tire inflation warning lights to be intalled on all their car and trucks and tring to make it into a industry standard lol

Jrfish007

iTrader: (3)

Nitrogen is mostly useless in normal tires. The reason for nitrogen is to prevent oxidation of the inside of the walls of the tire. No oxygen inside the tire, no oxidation. Oxidation of the rubber in side the tire will weaken it over time. But the normal person only uses his/her tires for about 60,000 mile, maybe 75,000 if you are really lucky (or 30,000 if you're like me ). But anyway, nitrogen prevents this oxidation, so where is it inportant? When you use your tire for a LONG time. Semi's use their side walls for about 250,000 miles, they just keep retreading them, so over that many miles the sidewall can become oxidized and eventually weaken, causing a blow out when under a heavy load.

The idea that Nitrgoen will expand less than air is mostly bs. It is slightly true, but you talking about maybe a 0.1 psi difference, if that. For the most part, all the air in your tire (rather it be nitrgen or normal air) is all pretty much consdiered idea gas and falls under the ideal gas law of PV=nRT.

But I know some people like nitrogen, so each person their own

As for the Taco Bell, if you find the solution let me know

shroomster

in doing so won't they need to install valve stem p.s.i monitors? those wireless tiny inch by 1/2 inch boxes connected to the inner part of the valvestem? that junk is gonna cost ....woooooo

Jrfish007

iTrader: (3)

yeah, I'm not sure how they are going to do that. I know the polymer division here at the Univeristy just finished a patent for a polymer that changes colors under different stress. So when the tire is with in limits it is a normal black (or maybe clear, I forget) and if it becomes under inflated or over loaded it turns red or something like that. So it could be built right into the tire where a patch or maybe the entire tire changes colors with improper loading.

But I think Ford said they wanted a dummy light inside the car, so yeah, that would be wireless I guess That would be costly...... The tire changing color thing sounds like a better option to me, but if I where incharge....

shroomster

honestly that polymer color is very intriguing, but you know as well as i do that there will be people willing to risk their lives for the sake of having a colored tire to match there vehicle (say 15 p.s.i is blue, they will run 15 just to get the 'look') thats just my opinion

but damn that is pretty cool that you guys were able to come up with that...

Jrfish007

iTrader: (3)

lol... yeah, well colored tires have been around for about 10 years, just nobody actually wants to make them because where exactly do you stop. I mean how many colors do you want to make, and then which colors to make? It would just be a nightmare.

But yeah, I personally don't make polymers, I just know a bunch of people who do that, University of Akron is famous for that, the main R&D for Firestone and Goodyear is done here in Akron. I work on catalyst (like the ones in your catalytic converter) and fuel cells.

igetmadchocha

that so;unds good bigger gas tank

sage_

drove home from college for the weekend, did some driving while i was at home, and then drove back to college sunday night when the fuel light turned on. when the light goes on, i'm pretty sure i have ~3 gallons left, so if you figure you get 25 mpg, then you can drive at least 75 miles on E... well i got 58.2 miles when my engine suddenly shut off on me when i was 1 mile from my exit . i was pissed because i wanted to get back and start drinking. anyways, my college's campus safety drove out to me with some gas and i made it home just fine.

*p.s.*I routinely run my tanking to down to the fumes, unless it’s cold out, and I normally drive at least 60 miles before I finally refill my tank and find out I had .2-1 gallon left.

Jrfish007

iTrader: (3)

I thought the light came on when you have about 1.7 gallons left.... I think it's in the manual, but I'm pretty sure it is not 3 gallons.

ncirom2003

iTrader: (7)

no my light comes on with three gallons left all the time.

DOES ANYONE HAVE A PIC OF WHERE THE NEEDLE IS RIGHT AFTER FILLING UP AND TOPPING OFF LIKE 4CENTS MORE?
i recently changed gauge lights and needles arent perfect so i figure this is the best way to fix it.

sage_

in my mom's 1999 crv ex and 2002 piliot ex their manual says that when the E lite goes on, they have 3 gallons left. so i would go look in my 5 speed 2002 ex manual, but it's snowing like crazy in Mi right now... try it out sometime, when your E light turns on, see how far you can drive your car...

as far as how far the needle goes up, on my car it goes like a cm above the Full hash mark line.