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  #13  
Old 10-27-2015, 09:00 PM
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Originally Posted by jeepgcoman View Post
Funny about that, Jeff, I've never been able to give it a "real good" test at or near sea level. I've driven it on trips at or near sea level (the Oregon Coast), but there are too many small towns all down the coast, and the speed limit in Oregon is only 55 mph on most highways. The best I've done on one of those trips was around 21 mpg. I've also done a couple trips to Vegas, but that is over more mountainous terrain (a few over 7000 ft.) before you start dropping down into Vegas. I have gotten around 22 on one of those though. The best economy for me is around home (~3000 ft.) where I can run non ethanol fuel and the terrain is more hilly than mountainous. One other thing I've noticed is that the economy falls off a little with the 20 in. wheels and huge tires on it. Still, since all the mods., I've only gotten less than 20 mpg. about 3 times in about 3 years.

Haven't done any mod. in nearly two years now and I am getting the "itch" again. I am actually thinking of putting a low boost (~5 PSI) supercharger on it, but I am having trouble getting past the price. When I started all this, my main goal was better fuel economy with slightly better fuel economy without any real invasive engine work. So far it's all worked out well, but a blower is a whole different game. For sure I'd never be able to keep my foot out of it then, LOL. So far, my research has found that, if you can keep your foot out of it, it will improve the fuel economy to some degree, but the break even point would be more than several years down the road. I do tend to keep my vehicles for a long time (longest was my classic Mercedes....29 years), so it may be OK in the long run.

If I get one, it'll probably be a Vortech unit, as most of it is also bolt on without requiring any engine teardown. At about 8 PSI they're suppose to be worth about 100-120 rwhp. but I'd be happay with about 80-100 more. I am sure I could deal with that though.
I see. I think 6 would be a more useable number tho. That should net you 90 or so and slightly better airflow off boost. Plus then you'll have a touch better power when you stab the loud pedal

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  #14  
Old 10-27-2015, 09:09 PM
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Re: 5.7 hemi questions

Ya, 8 would be even better, but my 06 is an early on (built Aug. 05) and some of those are the ones that dropped the valves. Just want to be a little safe rather than sorry. The up side to that (if I blew the engine) is that then I could spend a ton more $$$ and build it the way it should have been built in the first place.
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Old 10-27-2015, 09:15 PM
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Originally Posted by jeepgcoman View Post
Ya, 8 would be even better, but my 06 is an early on (built Aug. 05) and some of those are the ones that dropped the valves. Just want to be a little safe rather than sorry. The up side to that (if I blew the engine) is that then I could spend a ton more $$$ and build it the way it should have been built in the first place.
I could easily get the power I want if I had like 15k laying around lol
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  #16  
Old 10-27-2015, 10:10 PM
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Re: 5.7 hemi questions

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I could easily get the power I want if I had like 15k laying around lol
I hear you. I'd still like to build an all out hot rod six, just so I could waste some of the big V-8's.

Many years ago, I had a buddy that had a blown 49 Ford (painted "Grandma Gray") flathead V-8....about 200 cu. in. We'd go to the local drive in and ask if any of these big hot rod Chevys and Fords wanted to race a flathead. They'd all laugh until he blew their doors off. No one ever came close, not even the big block Chevys and Dodges. Now that was a hoot. Ahhh, the good old days.
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  #17  
Old 10-29-2015, 09:55 PM
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Re: 5.7 hemi questions

Hello everyone!!

Is a 5.8 mpg normal on a Hemi? I did changed the original air filter to a K&N. Could the K&N upgrade decrease the miles per gallon?

Thanks!!
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  #18  
Old 10-30-2015, 08:58 AM
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Originally Posted by GCOV View Post
Hello everyone!!

Is a 5.8 mpg normal on a Hemi? I did changed the original air filter to a K&N. Could the K&N upgrade decrease the miles per gallon?

Thanks!!
Not normal at all. Just swapping filters won't kill the mileage. I think something else is at play here....
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Old 10-30-2015, 09:28 AM
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Re: 5.7 hemi questions

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Originally Posted by GCOV View Post
Hello everyone!!

Is a 5.8 mpg normal on a Hemi? I did changed the original air filter to a K&N. Could the K&N upgrade decrease the miles per gallon?

Thanks!!
So, what do you have......year and mileage? If it's that bad...and that is really bad, you may have tune issues, O2 or other sensor issues, and perhaps a host of other things. Also, is the tire size stock?
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  #20  
Old 10-30-2015, 12:09 PM
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Re: 5.7 hemi questions

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Originally Posted by jeepgcoman View Post
So, what do you have......year and mileage? If it's that bad...and that is really bad, you may have tune issues, O2 or other sensor issues, and perhaps a host of other things. Also, is the tire size stock?
Hi, thanks for your reply. Itīs a 2014 Overland with 18718 miles on it; I brought it from the US to Shanghai where I live now. It was shipped on August 12 and arrived on September 19, but I actually received it on October 14 because of customs clearance. During all this time the car was turned off and had an almost empty tank. This 5.8 average mpg is from the first refueling I did since it arrived to China. Today it had its second refueling. We haven’t used it very often.

Besides the terrible mpg, the car runs great, it has lots of power and I haven’t felt any engine issues nor seen an engine warning light. I used 95 octane gasoline. Today I refueled with 92 and there is a 98 available as well. It has 2480 miles left until the next oil change. Tire size is stock, 20"
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  #21  
Old 10-30-2015, 02:06 PM
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Originally Posted by GCOV View Post

Hi, thanks for your reply. Itīs a 2014 Overland with 18718 miles on it; I brought it from the US to Shanghai where I live now. It was shipped on August 12 and arrived on September 19, but I actually received it on October 14 because of customs clearance. During all this time the car was turned off and had an almost empty tank. This 5.8 average mpg is from the first refueling I did since it arrived to China. Today it had its second refueling. We haven’t used it very often.

Besides the terrible mpg, the car runs great, it has lots of power and I haven’t felt any engine issues nor seen an engine warning light. I used 95 octane gasoline. Today I refueled with 92 and there is a 98 available as well. It has 2480 miles left until the next oil change. Tire size is stock, 20"
Was the battery disconnected for the move? If so let the evic register 300 miles before it will read accurately
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Old 11-01-2015, 10:14 AM
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Re: 5.7 hemi questions

Damn!!
missed buying good condition low km hemi!!
Well stick with the 3.7 for now. Besides, I love my 3.7 V6
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  #23  
Old 11-05-2015, 01:33 AM
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Re: 5.7 hemi questions

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Was the battery disconnected for the move? If so let the evic register 300 miles before it will read accurately
Got it!! I will keep you posted. Thanks!!
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Old 11-09-2015, 10:40 AM
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Re: 5.7 hemi questions

Hit the reset button for MPG for a more realistic realtime display, as IIRC it averages the last 50 km of driving. Refineries have 2 types of knock engines to test octane, and octane numbers in Japan are just for Motor octane, while in the US, we average Research and Motor octane to get the final number. R+ M / 2. 98 Octane in Japan is similar to our 93 Octane.
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