258 fuel economy - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > 258 fuel economy

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineBill Baird Motorsports DIY parts - NalinMFG.comComponent speaker deal for your dash - NalinMFG

Reply
Unread 07-10-2004, 02:54 PM   #1
eprobe
Registered User
1981 CJ5 
 
Join Date: Jun 2001
Location: Salt Lake City, utah
Posts: 29
258 fuel economy

I'm interested in what kind of fuel economy people out there are getting w/ their 232/258s. I get about 15 mpg w/ a 1bbl Carter on a 232 w/ 3.31 gears and 31.5" tires. Does anybody's Jeep do better and what did you have to do to achieve that? I'm particularly interested in people who may have swapped heads w/ a 4.0 or added EFI or TFI or an HEI.

Thanks,

Eric

eprobe is offline   Reply With Quote
Unread 07-10-2004, 06:06 PM   #2
jeepsarecool
Registered User
1982 CJ7 
 
Join Date: Jan 2003
Location: Alabama
Posts: 1,138
I get 14.5 mpg with 33" tires and a Weber 38. Not sure about my gears.
__________________
Check out my Art


CJ7 - God's gift to the masochist.
jeepsarecool is offline   Reply With Quote
Unread 07-10-2004, 07:13 PM   #3
djfuzzy
Web Wheeler
 
Join Date: Jun 2004
Location: Twenty-nine Palms, California
Posts: 1,219
I figure I get about 17mpg - but....all of my guages are out of whack except for my odometer so I don't really know.
__________________
USMC 2006-Present

Searching for a CJ again

Sold: 2000 TJ
1983 CJ7 Renegade
djfuzzy is offline   Reply With Quote
Unread 07-11-2004, 10:10 AM   #4
CJeep
Alpha dog
 
CJeep's Avatar
1982 CJ8 
 
Join Date: Apr 2001
Location: Near Fairfield, CT
Posts: 1,207
With the MPI kit, 31" 5-speed, and 3.31, I get over 20 mpg, close to 25 at times, on the highway, if you can beleive that. That's really the only time I calculate it.
__________________
'82 Scrambler - NV4500/4.5" lift/33" Toyo MTs/4.0/twin stick, and my windshield washers work! Full 1/2 cab Cage

2004 Grand Limited 4.7 HO - OH Boy!

2010 Grand Laredo 5.7 Hemi - SICK - work vehicle -gone - replaced by an 08 Tahoe - nice ride.

"Both my Doberman and my Jeep can accurately be described as 'black and rust.'"

"I got a fever . . . and the only prescription is more cowbell"
CJeep is offline   Reply With Quote
Unread 07-11-2004, 10:48 AM   #5
gosupes
Registered User
1986 CJ7 
 
Join Date: Jun 2004
Location: Monroe, WA
Posts: 1,527
Between 15 and 18 depending on type of driving with 4.10 gears, 31" tires and 5 speed trans.
__________________
1986 CJ7, 4.2 w/4.0 head, TFI-HEI hybrid ignition, Clifford manifold w/Holley 390 w/cold air intake, OBA, 4.5" lift, Woody CV shaft and Tattons in front, 4.10 gears - lunchbox in front, Truetrac in the back, twin-sticked, blower upgrade for running topless, trying to keep it simple.

It's just a Jeep, and if you don't wheel it once in a while, it's not even that.
gosupes is offline   Reply With Quote
Unread 07-11-2004, 11:34 AM   #6
80cj
Web Wheeler
 
80cj's Avatar
1980 CJ5 
 
Join Date: May 2002
Location: Hawaii
Posts: 5,754
Mine is a 80 CJ-5 with 4.10 gears 31 inch tires and a T-176. I haven't corrected the speedo since installing the 4.10s. Mileage is lousy ...probably about 12-13 mpg. I used to get between 15 and 17 with the old 3.54 gears.
80cj is offline   Reply With Quote
Unread 07-11-2004, 12:10 PM   #7
SamFromCO
Registered User
 
Join Date: Mar 2002
Location: Aurora, CO
Posts: 404
'86 CJ7, 258 w/Mopar MPI kit, 5 speed transmission, 35" tires, 4.56 gears=20 mpg highway (I seldom drive it around town so I don't know about that)
__________________
'86 CJ7, 258 w/Mopar MPI, 4.56 gears, rear Detroit/front Truetrac, full cage, OBA, 8274, 4" lift via Alcans/Rancho, 35's on beadlocks, other stuff. Built for rocks, mud is a four letter word.
SamFromCO is offline   Reply With Quote
Unread 07-11-2004, 12:55 PM   #8
jeepsarecool
Registered User
1982 CJ7 
 
Join Date: Jan 2003
Location: Alabama
Posts: 1,138
Quote:
Originally Posted by SamFromCO
'86 CJ7, 258 w/Mopar MPI kit, 5 speed transmission, 35" tires, 4.56 gears=20 mpg highway (I seldom drive it around town so I don't know about that)
20 mpg???? Are you suuuure about that?
__________________
Check out my Art


CJ7 - God's gift to the masochist.
jeepsarecool is offline   Reply With Quote
Unread 07-11-2004, 03:47 PM   #9
OL YELLAH
Member
 
Join Date: Nov 2003
Posts: 149
14-15 mpg with the engine mods listed below, 3-speed, and 3.73 gears. That's pretty much all highway driving.
__________________
[B]1979 Jeep CJ-5; 1972 258 (Pacesetter Header, Weber Carb, Wrangler Aluminum Intake, 2.5" Exhaust Straight Through w/ Thrush Mufflers); 2.5" BDS Lift; 1" Daystar Body Lift, Herculiner; RJS Belts; 33" Interco Trxus M/T Tires; Xtreme Alloy Wheels; 2.5" Perfomance Wheel Spacers; TFI Upgrade.[/B]
OL YELLAH is offline   Reply With Quote
Unread 07-11-2004, 05:40 PM   #10
SamFromCO
Registered User
 
Join Date: Mar 2002
Location: Aurora, CO
Posts: 404
Quote:
Originally Posted by jeepsarecool
20 mpg???? Are you suuuure about that?
Yep, I've checked it several times. And, if you found that hard to believe you'll probably have a harder time with this, that's over the mountains. About the only time that I ever really check mileage is on my trips from Denver to Moab and back. I believe that my odometer is pretty close and have checked it several times with my GPS. Also I roughly know the distance between gas stops. 19-20 mpg! The only catch is that I have to run premium unleaded to keep the motor from pinging.
__________________
'86 CJ7, 258 w/Mopar MPI, 4.56 gears, rear Detroit/front Truetrac, full cage, OBA, 8274, 4" lift via Alcans/Rancho, 35's on beadlocks, other stuff. Built for rocks, mud is a four letter word.
SamFromCO is offline   Reply With Quote
Unread 07-11-2004, 09:28 PM   #11
Aphelion79
Registered User
 
Join Date: Oct 2003
Location: Omaha, NE
Posts: 1,120
Quote:
Originally Posted by jeepsarecool
Not sure about my gears.

Any idea what rear axle you have?
__________________
1982 CJ7
Iron Duke "Hurricane" 151 CID 2.5L 4-Cyl
T177 Tranny | Dana 300 T-Case
Dana 30 Front | AMC 20 Rear
Aphelion79 is offline   Reply With Quote
Unread 07-12-2004, 10:16 AM   #12
jeepsarecool
Registered User
1982 CJ7 
 
Join Date: Jan 2003
Location: Alabama
Posts: 1,138
Quote:
Originally Posted by Aphelion79
Any idea what rear axle you have?

Yeah, I have the AMC 20 rear.
__________________
Check out my Art


CJ7 - God's gift to the masochist.
jeepsarecool is offline   Reply With Quote
Unread 07-12-2004, 05:19 PM   #13
Aphelion79
Registered User
 
Join Date: Oct 2003
Location: Omaha, NE
Posts: 1,120
Quote:
Originally Posted by jeepsarecool
Yeah, I have the AMC 20 rear.
To find your gear ratios (if stock and no one has done any upgrades etc) look at the rear of your 20

Rear View
Driver's Side (|)---=(+)=---(|) Passenger's Side

The right most = sign is the edge of the pumpkin that has either one letter or two letters sticking out of it. This is right where the axle tub fits into the differential. The letter(s) represent the current gearing from the factory.

Code:
'81 and earlier CJs
Narrow Track AMC 20  
Code  Gear Ratio  Diff Type  
AA  2.73  Open 
DD  2.73  Trac-Lok 
BB  3.31  Open 
CC  3.31  Trac-Lok 
A  3.54  Open 
N  3.54  Trac-Lok 
GG  3.73  Open 
Q  3.73  Trac-Lok 
L  4.10  Open 
M  4.10  Trac-Lok 


'82 up CJs
Wide Track AMC 20  
Code  Gear Ratio  Diff Type  
D  2.73  Open 
DD  2.73  Trac-Lok 
B  3.31  Open 
BB  3.31  Trac-Lok 
A  3.54  Open 
AA  3.54  Trac-Lok 
H  3.73  Open 
HH  3.73  Trac-Lok 
C  4.10  Open 
CC  4.10  Trac-Lok
Mine had a single "A" sticking out (not stamped INTO the metal) showing 3.54 gearing with Open differentials (no limited slip).
__________________
1982 CJ7
Iron Duke "Hurricane" 151 CID 2.5L 4-Cyl
T177 Tranny | Dana 300 T-Case
Dana 30 Front | AMC 20 Rear
Aphelion79 is offline   Reply With Quote
Unread 07-13-2004, 10:18 AM   #14
jeepsarecool
Registered User
1982 CJ7 
 
Join Date: Jan 2003
Location: Alabama
Posts: 1,138
'82 up CJs
Wide Track AMC 20
Code Gear Ratio Diff Type
D 2.73 Open
DD 2.73 Trac-Lok
B 3.31 Open
BB 3.31 Trac-Lok
A 3.54 Open
AA 3.54 Trac-Lok
H 3.73 Open
HH 3.73 Trac-Lok
C 4.10 Open
CC 4.10 Trac-Lok





Hey, thanks for the info. I went out and checked, and if it is stock (and I'm fairly sure it is), I have the 3.31 open gears. Is that a good gear ratio? It seems to work ok with my T5 and 33" tires.
__________________
Check out my Art


CJ7 - God's gift to the masochist.
jeepsarecool is offline   Reply With Quote
Unread 07-13-2004, 10:22 AM   #15
Aphelion79
Registered User
 
Join Date: Oct 2003
Location: Omaha, NE
Posts: 1,120
Quote:
Originally Posted by jeepsarecool
Hey, thanks for the info. I went out and checked, and if it is stock (and I'm fairly sure it is), I have the 3.31 open gears. Is that a good gear ratio? It seems to work ok with my T5 and 33" tires.
Well concidering its a final drive ratio it all kinda depends on what else you have... tranny, transfer case ratios .... tire size, and what you plan on doing with it... For me... I could stick with my Dana 300 and reduce it to 4:1 low and still have my high range that will work with my 4 spd on the highway... I'm not entirely too sure how well that would work... but with my 4 banger i shouldnt be able to beef out that much stress anyway lol...
__________________
1982 CJ7
Iron Duke "Hurricane" 151 CID 2.5L 4-Cyl
T177 Tranny | Dana 300 T-Case
Dana 30 Front | AMC 20 Rear
Aphelion79 is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.