Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: lil_me on April 27, 2006, 10:33:24 AM

Title: 4.0 Cherokee MPG
Post by: lil_me on April 27, 2006, 10:33:24 AM
Anything that might increase the MPG I get, getting about 15 at the minute, just wondering if there is any modifications which might squeeze a few more miles out, especially as petrol is about 97.9 up here at the minute  :shock:
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Post by: tim_aka_tim on April 27, 2006, 10:56:24 AM
Sounds about right. Everything you read about saving MPG tends to be snake oil, but if you try not to drive it like you stole it i.e. very moderate acceleration, that should help. Also, drive at the speed limit or slower and never go above 60! When you're on a long run, use the cruise control to keep your speed constant. My grand went from 25 to 28mpg just by doing that.
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Post by: Anonymous on April 27, 2006, 10:58:04 AM
try wearing lighter shoes!!! :lol:
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Post by: lil_me on April 27, 2006, 11:11:06 AM
I only have little shoes  :cry: ?

Cruise control on mine doesn't seem to be working, might have to make another post about that  :lol:
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Post by: Mike Pavelin on April 27, 2006, 11:20:55 AM
Please send some of that cheap petrol down here and remember the XJ trip computer uses US gallons which are smaller, so you're going to be doinh more MPG than it says.
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Post by: tim_aka_tim on April 27, 2006, 11:28:52 AM
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why not go over 60


Jeeps have the aerodynamics of a brick towing a parachute. More speed = more air restistance. Fuel consumption goes up exponentially at much above 50, but going that speed on the motorway is dangerous so 60 is a compromise.

No-one ever bought a jeep to save money!
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Post by: lil_me on April 27, 2006, 11:33:00 AM
:cry: ok I suppose I will have to leave the lead boots at home

 :shock: I thought we had the most expensive fuel prices, I must be wrong then
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Post by: isle of man on April 27, 2006, 11:46:24 AM
over £1.03 here.......count your self lucky as my wrangler is in single figures per gallon.



peter henry
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Post by: tim_aka_tim on April 27, 2006, 11:48:49 AM
97.9 is expensive. petrolprices.com says 94.9 is cheapest in durham area.
If you're doing some serious miles, maybe you should consider an lpg conversion.

Incidentally, a high flow exhaust and air induction *might* help, but the hundreds it will cost aren't likely to be made back in fuel savings. Make it sound nice though  :lol:
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Post by: Anonymous on April 27, 2006, 11:50:49 AM
Get a K&N panel filter that will get you 1-2 more mpg :D
Try Yates and Bloomfield off eblag Their in Rossendale or google www.ybfilters.co.uk (http://www.ybfilters.co.uk)
Quality and speed of service was 1st class
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Post by: stevegreen0 on April 27, 2006, 12:35:23 PM
I see Mike said that the trip Computer uses US Gallons which are smaller and so you are actually getting a slightly better mpg than it shows. (I have heard this before). Is there an easy way to convert the reading i.e. multiply the computer figure by xxx to give the UK figure?

Regards.

Steve
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Post by: tim_aka_tim on April 27, 2006, 12:47:24 PM
multiply by 1.2
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Post by: chrisjones on April 27, 2006, 12:49:11 PM
Have a serious look at converting to LPG. 40p per litre :twisted:

70-80mph on the motorway is fine.

(and that's with 31" mud tyres and a lift. :wink: )
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Post by: Mort on April 27, 2006, 01:36:50 PM
Quote from: "Mike Pavelin"
Please send some of that cheap petrol down here and remember the XJ trip computer uses US gallons which are smaller, so you're going to be doinh more MPG than it says.


Gonna take my life in my hands, and beg to differ with you on that Mike.  #-o
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Post by: Mike Pavelin on April 27, 2006, 02:31:03 PM
I guess it's possible, but when they were supplied new they had stickers on them informing the driver of the discrepency, but they were removed on pre delivery inspection.
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Post by: lefty on April 27, 2006, 02:46:13 PM
I use mine around town most of the time and driving to the pay'n'play and to the shooting club once a week. Maybe 100-150 miles a week if that.

I can't help giving it the beans off the lights to embarass the baseball-capped chavs in their corsas etc...  :shock:
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Post by: lil_me on April 27, 2006, 02:56:07 PM
Quote from: "chrisjones"
Have a serious look at converting to LPG. 40p per litre :twisted:

70-80mph on the motorway is fine.

(and that's with 31" mud tyres and a lift. :shock:
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Post by: AdrianW on April 27, 2006, 03:24:37 PM
Quote from: "Mike Pavelin"
I guess it's possible, but when they were supplied new they had stickers on them informing the driver of the discrepency, but they were removed on pre delivery inspection.


My handbook has the advisory sticker in it - mulitply by 1.2, etc

Only got about 17 mpg on a recent trip to Devon and back, but can't really complain as cruise was set 'quite high'  8) Pretty sure that running taller tyres takes its toll though!
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Post by: chrisjones on April 27, 2006, 03:56:25 PM
Quote from: "lil_me"
Quote from: "chrisjones"
Have a serious look at converting to LPG. 40p per litre :twisted:

70-80mph on the motorway is fine.

(and that's with 31" mud tyres and a lift. :shock:


Take a look at a single point LPG conversion then.  You should be able to get it done for less than £1000.  It all depends on how many miles you do, as to whether it's worth the money or not. I do about 15,0000 a year in mine, so it was. :wink:
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Post by: Mike Pavelin on April 27, 2006, 04:38:35 PM
AW. remember if you have tall tyres and you havem't corrected the speedo gearing, this will give you fewer MPG on your trip computer, too.
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Post by: prozac on April 27, 2006, 05:31:35 PM
Quote from: "lefty"
I use mine around town most of the time and driving to the pay'n'play and to the shooting club once a week. Maybe 100-150 miles a week if that.

I can't help giving it the beans off the lights to embarass the baseball-capped chavs in their corsas etc...  :shock:


I did!!!
But mine's LPG :lol:  :lol:
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Post by: Anonymous on April 27, 2006, 07:00:53 PM
Found I used to get around 20-22 with standard 225 raod tyres on when I first had it.

Now with 235 AT's, a 3 inch lift & snorkel fitted (standard Mopar air filter though watching out for a K&N) I now get 18-19.

Can get low 20-21 on a motorway run with cruise set about 70-75 tho.

Cane it tho & they will drink it.

Running a standard TJ on 225 AT's & thats doing about 18.

God knows what that will drop to when the snorkel, K&N & winch etc is fitted but as everyone says, dont buy a Jeep for economy unless mileage / LPG is for you  :wink:
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Post by: Psychoman on April 27, 2006, 07:29:11 PM
We found fitting a snorkel actually helped with fuel economy on our Cherry - above about 50 you seem to get a ram air effect - which is nice. :wink:
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Post by: wrangler on April 27, 2006, 09:10:19 PM
I think 15 lamp post's to the gallon is good i get about 12 :roll:
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Post by: Dingo on April 27, 2006, 10:37:15 PM
Yea, I was gonna say stop complaining, last time the CJ was out I got about 8 mpg.
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Post by: chrisjones on April 28, 2006, 12:45:14 AM
Quote from: "Dingo"
Yea, I was gonna say stop complaining, last time the CJ was out I got about 8 mpg.


You've been told before about thet drink problem! :lol:
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Post by: JamesH on April 28, 2006, 09:26:00 AM
I'd agree with Mort. My facelift 4.0 is accurate when running on petrol (way out on LPG??!?) and my dad has a facelift 2.5 that also has an accurate / imperial trip computer.

It's still more accurate to calculate from how much goes in and how many miles are done though.

FWIW I'm getting about 15 MPG on LPG with stock gears, 3-4" lift and 31" BFG MTs. I don't drive consistently fast/slow, long journeys or short - it always returns similar  :roll:
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Post by: Anonymous on April 28, 2006, 10:03:48 AM
Tried driving the TJ with a light foot, got ~ 17mpg... drive it a bit nutty now... and get 16... Mostly short journies.... with 31's and stock.... am hoping and praying it get's a bit better if I re-gear....
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Post by: Anonymous on April 28, 2006, 10:06:38 AM
When I get the FJ back I'll work out the consumption ... 35's, rollcage, brick like aerodynamics oh and the 5.7l V8 ... perhaps I wont bother  :lol:
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Post by: chrisjones on April 28, 2006, 10:16:14 AM
Quote from: "matt the sign"
When I get the FJ back I'll work out the consumption ... 35's, rollcage, brick like aerodynamics oh and the 5.7l V8 ... perhaps I wont bother  :shock:  :lol:
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Post by: Anonymous on April 28, 2006, 10:18:19 AM
I thought that was in GPMs.....
 :twisted:

Have real fun, work out the cost per mile for the Nylint :D
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Post by: Anonymous on April 28, 2006, 10:54:43 AM
The Nylint would be cheap ... $150 divided by 4330 miles = 0.01pence per mile  :lol:
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Post by: AdrianW on April 28, 2006, 11:06:56 AM
Quote from: "Mike Pavelin"
AW. remember if you have tall tyres and you havem't corrected the speedo gearing, this will give you fewer MPG on your trip computer, too.


Very true, worked it out when I got back though - it's on LPG so it's still cheap - major advantage at the moment being that while petrol's going up in price, LPG hasn't changed (yet) around here.

Guess the Nylints work out cheap - used to have a 1/8 nitro engined r/c car - that was dear at £23.00 a gallon :shock:
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Post by: lefty on April 28, 2006, 01:32:18 PM
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£23.00 a gallon


Won't be long till we're paying that - Brent's at $71... :o
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Post by: lefty on May 01, 2006, 11:43:45 AM
Well, yesterday i managed an average 14.5mpg which I'm actually quite happy with.

215 miles on A-roads and about 60 on the Corrie Pass  :D
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Post by: Anonymous on May 01, 2006, 10:55:43 PM
currently getting 23 and a bit mpg, over 300 miles a tank, all A road stuff about 60-65mph, running 235-75-15's and have a lead foot, WTF are you lot doing with your petrol??
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Post by: Mort on May 02, 2006, 10:29:41 AM
Quote from: "offroading.net"
currently getting 23 and a bit mpg, over 300 miles a tank, all A road stuff about 60-65mph, running 235-75-15's and have a lead foot, WTF are you lot doing with your petrol??


Petrol?  Ah, that would explain it then - we run ours on sea water! :wink:
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Post by: Anonymous on May 02, 2006, 10:35:08 AM
Quote from: "offroading.net"
currently getting 23 and a bit mpg, over 300 miles a tank, all A road stuff about 60-65mph, running 235-75-15's and have a lead foot, WTF are you lot doing with your petrol??


You must have the only lead foot made of helium :)
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Post by: Anonymous on May 02, 2006, 08:28:48 PM
the trick is quick upto 45 and ease of the loud pedel a touch, the box jumps into 4th, much better mpg then  :D
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Post by: Anonymous on May 02, 2006, 08:31:00 PM
Or, you get to 30 and just shove the lever in 4th if you so feel  :twisted: