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  #13  
Old 02-27-2014, 08:47 PM
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Re: Tire size (CRD specific version)

He is correct, the tires increase rolling resistance, unsprung weight, and increase your coefficient of drag. It is a physical impossibility to get better mileage because these things both cost you effective power and increase your load. It cannot happen.

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  #14  
Old 02-27-2014, 09:04 PM
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Re: Tire size (CRD specific version)

I never said the mpg was due to the larger tires. Try reading the thread. I said i het 33-34mpg on the evic despite larger tires at 80mph on flat highway period. Some of you just make stuff up to argue about.
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Old 02-27-2014, 10:47 PM
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Re: Tire size (CRD specific version)

I will give it a shot, but I suspect I may need a slightly downhill grade to find the sweet spot.

yours truly,

DoubtingThomas

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Old 02-27-2014, 10:57 PM
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Re: Tire size (CRD specific version)

Well you were wrong about the onboard mpg calcs so there is a good chance that trend may continue.

you also seem to have a different GC than mine and different size tires .
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Old 02-28-2014, 05:06 PM
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Re: Tire size (CRD specific version)

Quote:
Originally Posted by Goonbash View Post
I never said the mpg was due to the larger tires. Try reading the thread. I said i het 33-34mpg on the evic despite larger tires at 80mph on flat highway period. Some of you just make stuff up to argue about.
I did read and carefully. You are claiming better mileage from an rpm drop DUE TO YOUR LARGER DIAMETER TIRES. Let me quote you... "There is a sweet spot with turbo vehicles where you arent making noticeable boost (which sucks gas) but where the compressor wheel is still helping the engine to be very efficient when you have larger tires that sweet spot rpm and throttle position happen at a higher road speed because bigger tires give less rpm at the same speed as smaller tires." ... end quote.

This is not a physical possibility because the losses easily overcome the drop in rpm. Also what the evic says has nothing to do with calculated mileage, this can only be derived by doing the math at the pump. Any other number from any other source is meaningless.

Stating facts is not arguing and the physics are not made up. You may as well claim you threw a ball in the air and couldn't find it so it must have left the planet and therefore gravity doesn't exist.

The reason it matters is because people will come by and read a post like yours and then think they can mount larger tires and get better mileage when they will not. If I was sitting around talking about it I would let it go because its not worth correcting but on a forum these things take on a life of their own.
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Old 02-28-2014, 05:12 PM
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Re: Tire size (CRD specific version)

Wrong again. The response you quoted was simply an explanation of why my car might get the gas mileage at 80mph, instead of say 65 or 70 mph. If you read the other guys post he asks what the secret to getting good mileage "at 80+ mph" was with bigger tires. I never said the reason for the mileage itself was due to larger tires. Is reading comprehension a weak spot for you? I was simply explaining to the other guy why the 'sweet spot' might be at higher road speed than with stock tires and NEVER mentioned it getting either better mileage than with stock tires or mentioned the mileage being due to larger tires. That is you arguing against things i never mentioned because that is obviously your MO.

since you seem to like forum 'yelling' in all caps:

i WAS CLAIMING THE HIGHER SPEED AT WHICH ThE VEHICLE GETS ITS BEST MILEAGE WITH THE LARGER TIRE SET UP WAS DUE TO LARGER TIRES (please quote where i ever said the mileage was better than with stock tires, you cant because i never said it), I NEVER EVEN COMPARED OR LISTED MY STOCK TIRE MILEAGE IN THIS THREAD SO YOU SAYING I CLAIMED BETTER MILEAGE DUE TO LARGER TIRES WHEN I NEVER EVEN MENTIONED THE NUMBER YOU SAY I WAS CLAIMING THE MILEAGE WITH LARGE TIRES WAS BETTER THAN, MAKES YOU OVER-ASSUMPTIVE AND UNREASONABLY ARGUMENTATIVE.

It is pretty obvious the quote you mentioned explains why the best mileage of the car when it has larger tires might happen at a higher road speed than the best mileage when it has stock tires. If i were claiming better mileage overall due to larger tires i would have listed the mpg with stock tires. Period!
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  #19  
Old 02-28-2014, 06:16 PM
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Whoa, calm down there bud. The reason it sounds so far fetched is because I don't know of any account of anyone being able to hit 30+ mpg at anything over 70 mph, much less with larger, heavier tires.

Keep in mind, those Duratracs are LTs and a bit heavier. When I replaced my Bridgestone duelers with the identical size Duratracs I lost 2 mpg.
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Old 02-28-2014, 06:20 PM
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Re: Tire size (CRD specific version)

AGAIN i never said i didnt lose mpg with bigger tires! I said that with bigger tires the evic reads 33-34mpg at 80mph on flat highway. And everyone 'in the know' saus the mpg readings, like the speedo and odo, should be reading slightly low with the larger tires. Those are the facts. I have 275/65r18s that read 33-34mpg at 80mph. When i dtop to 65-70mph the mpg reading drops to 27-28mpg.

As i explained earlier, it is hard to know the exact mpg loss with larger tires because the diameter throws off the mpg calcs in evic. I was told the evic would be taking the extra rotating mass and aero loss of bigger tires into account because that would show up in measured fuel consumption but since the mpg calcs are done by the computer assuming a 5% smaller tire, that you have to add 5% to the trip odometer, mpg, etc to get the real # but i dont know if that is truly accurate. So while i assume i lost mpg i cant say how much since the onboard calcs are off.

Most other people agree since the speedo and odometer read low with larger tires (meaning you are driving more miles than the evic thinks you are) the mpg should read low too.

my assumption is simply that with stock tires my GC diesel must have gotten 36-37mpg under good conditions (flat highway) at some speed below 80mph (since the best mpg speed would have been slightly lower than with big tires to be at the same engine rpm as the best mpg with bigger tires).
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Old 02-28-2014, 08:56 PM
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Re: Tire size (CRD specific version)

Quote:
Originally Posted by Goonbash View Post
Wrong again. The response you quoted was simply an explanation of why my car might get the gas mileage at 80mph, instead of say 65 or 70 mph. If you read the other guys post he asks what the secret to getting good mileage "at 80+ mph" was with bigger tires. I never said the reason for the mileage itself was due to larger tires. Is reading comprehension a weak spot for you? I was simply explaining to the other guy why the 'sweet spot' might be at higher road speed than with stock tires and NEVER mentioned it getting either better mileage than with stock tires or mentioned the mileage being due to larger tires. That is you arguing against things i never mentioned because that is obviously your MO.

since you seem to like forum 'yelling' in all caps:

i WAS CLAIMING THE HIGHER SPEED AT WHICH ThE VEHICLE GETS ITS BEST MILEAGE WITH THE LARGER TIRE SET UP WAS DUE TO LARGER TIRES (please quote where i ever said the mileage was better than with stock tires, you cant because i never said it), I NEVER EVEN COMPARED OR LISTED MY STOCK TIRE MILEAGE IN THIS THREAD SO YOU SAYING I CLAIMED BETTER MILEAGE DUE TO LARGER TIRES WHEN I NEVER EVEN MENTIONED THE NUMBER YOU SAY I WAS CLAIMING THE MILEAGE WITH LARGE TIRES WAS BETTER THAN, MAKES YOU OVER-ASSUMPTIVE AND UNREASONABLY ARGUMENTATIVE.

It is pretty obvious the quote you mentioned explains why the best mileage of the car when it has larger tires might happen at a higher road speed than the best mileage when it has stock tires. If i were claiming better mileage overall due to larger tires i would have listed the mpg with stock tires. Period!
You were claiming better mileage due to your tires, at least be a man and own up to it instead of trying to pretend that you were only claiming better mileage at an isolated RPM so you get off on a technicality. It makes no difference anyways because it didn't happen. Your mileage is not better at 80 than it is at 70, it is worse. You are not getting better mileage anywhere. There is no special set of physics just for you.

I wasn't posting for your benefit, you are willfully ignoring truth which is easily obtained and common knowledge. I was posting for others who might read this thread that own cars that are driven in the real world. They will not get better mileage anywhere at any speed because they will not have the benefit of the special physics which apply to only your car. I have nothing more to add, the last word is yours. Be aware that if you go with inane drivel like "my evic says" I wont read it. The evic is meaningless.
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  #22  
Old 02-28-2014, 09:03 PM
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Re: Tire size (CRD specific version)

You really are a moron. You looked back and saw i never claimed what you accused and now like a 3rd grader you try to turn it around.

BTW if where are you getting your mpg numbets from if not ftom the evic???

Anyone reading this thread can see i never said the big tires gave me better mileage than stock. People like you who hijack threads to argue over things that were never even mentioned are the reason forums arent always helpful.
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  #23  
Old 02-28-2014, 09:35 PM
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Quote:
Originally Posted by Goonbash View Post
People like you who hijack threads to argue over things that were never even mentioned are the reason forums aren't always helpful.
Yep. You called it. Read the threads he's in and its not hard to see how he gets his jollies. Yawn.
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Old 03-02-2014, 07:13 AM
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Re: Tire size (CRD specific version)

To you excursion I will say this, I'm a life long car guy. My dad was what they used to call the head mechanic at Dodge garage. I grew up with cars, worked on them all my life, have built several frame off, the works. They are in my blood and I'm passionate about them and learning about them. I've actually been trying to stay out of many conversations because I know most people here are not hardcore about this stuff. My mission in life isn't to give you or anyone grief. I'm used to being on forums where Goon would have been raked over the coals for days. It appears I need to try harder at adapting to life in the burbs.
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