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Unread 05-04-2013, 05:36 PM   #31
pinky2252s
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Quote:
Originally Posted by doc8669 View Post
I was thinking of installing and CAI to get better numbers but I'm trying to decide if its worth it or not. We have some pretty cold winters up here and it would hinder the fuel consumption with the colder temperatures. I would probably have to put the stock one back and I don't want to do that

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Unread 05-04-2013, 05:49 PM   #32
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I guess that works lol

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Unread 05-05-2013, 05:42 AM   #33
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I agree with that the EVIC is not accurate at all, we have to do the math manually. I already gave up trying to reach the 20 MPG amd and am very satisfied with my 17 MPG highway (did the math manually) although my car runs without O2 sensor or Cat convertor.
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Unread 05-05-2013, 06:02 AM   #34
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The EVICs do seem to be much more accurate on the diesels though. My friends one and mine never seem to be out more than a couple of tenths of a MPG....so I dont bother hand calculating any more! Mind you I will when I get my new tuning box fitted, just to see if Im getting anywhere near the the claimed fuel savings!

Could be that the diesel injector is more tightly controlled and more easily monitored by the ECU on a diesel...not sure though.
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Unread 05-05-2013, 07:22 AM   #35
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Now that I changed my tires and the odometer/OBD speed data is about 7% off, the accuracy of my EVIC is much better, but still off. As for a CAI, for the purposes of fuel economy colder air is not always better. The hardcore MPG guys will often WARM the air to increase fuel economy.
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Unread 05-05-2013, 07:35 AM   #36
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The EVICs do seem to be much more accurate on the diesels though. My friends one and mine never seem to be out more than a couple of tenths of a MPG....so I dont bother hand calculating any more! Mind you I will when I get my new tuning box fitted, just to see if Im getting anywhere near the the claimed fuel savings!

Could be that the diesel injector is more tightly controlled and more easily monitored by the ECU on a diesel...not sure though.
Hi Alfaitalia,

First time I saw your nickname I thought you are Italian, by the way I follow your post as all of them make sense and an added value to me

Quote:
Originally Posted by lazyWJ View Post
Now that I changed my tires and the odometer/OBD speed data is about 7% off, the accuracy of my EVIC is much better, but still off. As for a CAI, for the purposes of fuel economy colder air is not always better. The hardcore MPG guys will often WARM the air to increase fuel economy.
As a fuel engineer, there is another crucial factor which I believe never been mentioned here, which is the base components of the gasoline blend itself, as different blends with same octane number and both complies with the specs but can be totally different in terms of energy released and consumption.
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Unread 05-05-2013, 07:39 AM   #37
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Hi Alfaitalia,

First time I saw your nickname I thought you are Italian, by the way I follow your post as all of them make sense and an added value to me


Cheers. I am half Italian on my mothers side....but the user name came from my previous forum life on Alfaforum when I was running an Alfa 156 V6 Veloce. Ciao!
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Unread 05-05-2013, 07:52 AM   #38
lazyWJ
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Originally Posted by veiri86 View Post


As a fuel engineer, there is another crucial factor which I believe never been mentioned here, which is the base components of the gasoline blend itself, as different blends with same octane number and both complies with the specs but can be totally different in terms of energy released and consumption.
This is interesting. It doesn't sound like something an operator has any control over, but might be helpful in recognizing the possible differences. Could you elaborate?
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Unread 05-05-2013, 08:19 AM   #39
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Quote:
Originally Posted by lazyWJ

This is interesting. It doesn't sound like something an operator has any control over, but might be helpful in recognizing the possible differences. Could you elaborate?
Some refiners or traders they add certain blends to achieve the target octane number, for example some traders they could get a good deal buying low octane gasoline, so they buy it and upgrade it in their plants by adding another blending component, for example some of them they use low molecular weight blends which can boost the octane number, but at the same time will boost the RVP (ratio vapor pressure) where there is a maximum limit for the RVP, the RVP in brief will give an indication for the volatility of that component. So if you use that gasoline with such components you might be having lower MPG than other gasoline blend.

Talking about refiners, some of them they are facing problem with one of the units that produces the high octane component and it is down, so they tend to use other available blend which not healthy to be used and not very feasible and it will put their gasoline on the higher side of the gasoline specs range, but they have no choice but using it to fulfill the local demand.


Mainly there are several specs for the gasoline where they have to stick with it such as the octane number, RVP, Oxygenates, and many others.

And by the way there are other blends contains component tends to form gum and fouling material in the tank causing plugging in the fuel system.

This is in brief but if anybody interested to go deeper in details with some boring chemical details I will be happy to help
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01' 4.7 Limited WJ 5" lifted, Rubicon Express 4.5" coil springs with IRO critical path setup and Bilstien 5100 shocks all around, JKS adjustable Trackbar (KOR bushings), JKS HD tie rod (MOOG problem solver Ends), JKS HD drag link (Moog Probel solver Ends), 4.56 Yukon ring and pinion, Moog HD SSD107 Steering Stabilizer, IRO Front drive shaft conversion, Stillen slotted rotors all around with Stillen brake pads, IRO adjustable A-Arm, 3" all the way Kolak Exhaust with High flow Magnaflow Cat. Converter and Flowmaster Super 50 Muffler, 285/70R17 AT Kumho (33") on 17" BlackWheel rims 909B, K&N Cold air intake, Four nozzles Bosch injectors, and Flashpaq 3780.

03' 4.7 H.O WJ 3" lifted, OME HD with 0.5" Coil spacers and Bilstien 5100 shocks all around, JKS adjustable Trackbar (KOR bushings), Moog Problem solver TRE's, IRO Front drive shaft conversion, IRO adjustable A-Arm, High flow magnaflow mini cats, high flow magnaflow cat, Flowmaster Super 44 muffler, 265/65R17 AT Yokohama on 17" Rays rims, and Flashpaq 3780
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Unread 05-05-2013, 08:34 AM   #40
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Quote:
Originally Posted by veiri86 View Post
Some refiners or traders they add certain blends to achieve the target octane number, for example some traders they could get a good deal buying low octane gasoline, so they buy it and upgrade it in their plants by adding another blending component, for example some of them they use low molecular weight blends which can boost the octane number, but at the same time will boost the RVP (ratio vapor pressure) where there is a maximum limit for the RVP, the RVP in brief will give an indication for the volatility of that component. So if you use that gasoline with such components you might be having lower MPG than other gasoline blend.

Talking about refiners, some of them they are facing problem with one of the units that produces the high octane component and it is down, so they tend to use other available blend which not healthy to be used and not very feasible and it will put their gasoline on the higher side of the gasoline specs range, but they have no choice but using it to fulfill the local demand.


Mainly there are several specs for the gasoline where they have to stick with it such as the octane number, RVP, Oxygenates, and many others.

And by the way there are other blends contains component tends to form gum and fouling material in the tank causing plugging in the fuel system.

This is in brief but if anybody interested to go deeper in details with some boring chemical details I will be happy to help
Very interesting stuff. In my area (Maritime Canada) all the gas comes from one refinery, and the different "retailers" just use their specific additive packs. I don't know if this would make it more consistent or if it could vary even from one source? Is getting one fuel instead of another just luck of the draw, or is there any way to be more aware of what you might be getting? Thanks for the info.
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Unread 05-05-2013, 08:41 AM   #41
veiri86
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Quote:
Originally Posted by lazyWJ

Very interesting stuff. In my area (Maritime Canada) all the gas comes from one refinery, and the different "retailers" just use their specific additive packs. I don't know if this would make it more consistent or if it could vary even from one source? Is getting one fuel instead of another just luck of the draw, or is there any way to be more aware of what you might be getting? Thanks for the info.
No body could know what you are having in the tank except three people, the supply chain guy who made the recipe of the blend, the lab guy who made the hand blend and tested it, and the trader in case there is a trader who bought it and upgraded it. So as you said it is matter of luck. But as long as all of them from the same source, I will tend to go to the fuel with the least additives as most of the additives will fix one spec and screw many others, especially these gasoline blends designed for more mileage.

And for sure avoid the patrol pumps with with old tanks as they could cause plugging in your fuel system due to the deposit.
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Build thread: http://www.jeepforum.com/forum/f197/...x-wjs-1872002/

01' 4.7 Limited WJ 5" lifted, Rubicon Express 4.5" coil springs with IRO critical path setup and Bilstien 5100 shocks all around, JKS adjustable Trackbar (KOR bushings), JKS HD tie rod (MOOG problem solver Ends), JKS HD drag link (Moog Probel solver Ends), 4.56 Yukon ring and pinion, Moog HD SSD107 Steering Stabilizer, IRO Front drive shaft conversion, Stillen slotted rotors all around with Stillen brake pads, IRO adjustable A-Arm, 3" all the way Kolak Exhaust with High flow Magnaflow Cat. Converter and Flowmaster Super 50 Muffler, 285/70R17 AT Kumho (33") on 17" BlackWheel rims 909B, K&N Cold air intake, Four nozzles Bosch injectors, and Flashpaq 3780.

03' 4.7 H.O WJ 3" lifted, OME HD with 0.5" Coil spacers and Bilstien 5100 shocks all around, JKS adjustable Trackbar (KOR bushings), Moog Problem solver TRE's, IRO Front drive shaft conversion, IRO adjustable A-Arm, High flow magnaflow mini cats, high flow magnaflow cat, Flowmaster Super 44 muffler, 265/65R17 AT Yokohama on 17" Rays rims, and Flashpaq 3780
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Unread 05-06-2013, 08:17 PM   #42
Jdellimited
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Originally Posted by miami5th View Post
I also have an 01 v8 limited. I get about 21mpg combined. Usually around 18-19 city and 22-23 highway. I am a moderate driver, sometimes I am conservative with the gas, other times I drive the suv hard. That v8 is fun to drive and hard to resist the throttle

Is your jeep utilizing overdrive?
Man, I wish I only get about 15.5 and I drive highway all the time, what grade of gas do you use? By the way i always try to be conservative with the gas but it is hard sometimes with the V8, lol.
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