What happened to my mpg's
12-08-2011, 07:58 PM
#12
JK Super Freak
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Originally Posted by dinojeep
Wow, 12? I'm thinking about making the jump to 4.88 and 37s someday but I dont want to see that number. I am a little lighter than you, I guess that would help. Interesting.
12-08-2011, 08:14 PM
#13
Wow that's surprising it's not like your new tires are huge either..... I had 33x12.5x17 not big enough now have 35x12.5x17 and I can see why guys go 37"
I also have a new front bumper with stinger and levelled 4" lift and get over 16mpg.... Get a superchip it helps a bit....
I also have a new front bumper with stinger and levelled 4" lift and get over 16mpg.... Get a superchip it helps a bit....
12-10-2011, 10:46 AM
#14
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Found the issue! My coil is bad. When it idles, the engine is smooth, but i guess when it is under load, one of the plugs doesn't fire. I have been a mechanic since I could hold a wrench and I have NEVER heard of anything like this. So, is there a performance coil out there that actually makes a difference?
Is this any good? http://www.4wd.com/Jeep-Engine-Perfo...fD31740-9300RD
With these? http://www.summitracing.com/parts/ETP-E3-66/
Is this any good? http://www.4wd.com/Jeep-Engine-Perfo...fD31740-9300RD
With these? http://www.summitracing.com/parts/ETP-E3-66/
12-10-2011, 03:10 PM
#15
JK Newbie
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19.2 with stock bicycle tires, 15 with 285/75s on mine. It IS the tires. You're adding width (rolling resistence), height (leverage against drivetrain), weight (almost double the weight of the stock 225s), and air turbulence under and around your Jeep. Basically everything you can possibly do to kill mileage, that's what you've done with large tires.
Hence, the reason I sold my 285s after only 2 months and just bought 265s this week.
Hence, the reason I sold my 285s after only 2 months and just bought 265s this week.
12-11-2011, 04:59 AM
#17
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With these? http://www.summitracing.com/parts/ETP-E3-66/
Also, when doing a replacement performance coil, you'll need new plug wires and to also increase your plug gap. If the manufacturer of the coil doesn't have a prescribed new plug gap, look for a different one.
12-11-2011, 05:07 AM
#18
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Originally Posted by SOBX
Found the issue! My coil is bad. When it idles, the engine is smooth, but i guess when it is under load, one of the plugs doesn't fire. I have been a mechanic since I could hold a wrench and I have NEVER heard of anything like this. So, is there a performance coil out there that actually makes a difference?
Is this any good? http://www.4wd.com/Jeep-Engine-Perfo...fD31740-9300RD
With these? http://www.summitracing.com/parts/ETP-E3-66/
Is this any good? http://www.4wd.com/Jeep-Engine-Perfo...fD31740-9300RD
With these? http://www.summitracing.com/parts/ETP-E3-66/
