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Well I think my carb is holding up now. What kind of gas mileage can I expect on this stock AMC 258 i6 / 4.2l with an m/c 2150? Running 3:58 (not sure exactly don't have my paper here) or so.
1978 CJ7
Silver paint with black hard top on 33" radials & eagle alumium rims. Good looking ride and have done lots of work to make it look and run great.
Stock equipment is 258 carb, power brakes, power steering, hard top & hard doors (per vehicle gross weight) tilt steering wheel, big brake package with large rotars & drums, T18 Trans with low 6.4 granny gear, Dana 20 transfer, Dana 30 front axle, Dana 44HD rear axle with 3.73 gears. True Trac ft & rear.
I was around jeeps in the 70's and drove a 1973 Jeep Truck. My family had 4 jeeps at the time. We also joined a jeep club back then too. So about 6 years ago looked for a Jeep CJ and found the vehicle above.
AMC 258 i6 / 4.2l can get pretty good mileage but "everthing" and to be correct and working well. Good to know the axle gears, along with the ??tire size, and the Transmission and what gear ratios. The jeep has to match the Transmission gears, axles gears, and tires size so the rpms are in the proper range.
Transmission Gears, Axle Gears and large tires not combined correctly, like using the 2.73 gears with 33 tires.
Jeep Mileage for the 70s and 80s jeeps;
Poor Set up 9-10 mpg Hwy
Ok set up 15
Good set up 18-19
VG set up 21-24
When we talk about mileage this is HWY mileage. Stop & go and town driving cannot be used for this promo. My CJ7 can get 23/24 HWY mpg range if I stay out of the pedal, try to keep rpms about 2200-2500. In the past I used vacuum...... gauge on the manifold to help teach me . The higer you can keep the vacuum level driving down the HYW the higher your mpg will be. When the vac is HIGH the throttle plates are almost closed and do not pass much fuel. Want to learn more... use a 6-8 vac hose and put the gauge in the passenger seat and go for a ride. The gauge reading will teach you how to drive.
In the early 70s I drove a Jeep Truck with a AMC 258 i6 / 4.2l 3 speed..... GREAT TRUCK. It got 23 mpg back then.
The CJ (ligher) borla headers, better weber carb, MSD Ignition, upgraded plug wires, TeamRush, a better set up for engine. This is a very good set up and drives like a new truck. It also gets great mileage...... 17/18 normal and 23/24 Hwy Mpg.
Carb, intake, exhaust, gears/tires, Header?, ignition, WATER Jacket Intake, coil, plug gap, autolite plugs, set up correctly can make a big difference for the collector jeeps.
1978 CJ7
Silver paint with black hard top on 33" radials & eagle alumium rims. Good looking ride and have done lots of work to make it look and run great.
Stock equipment is 258 carb, power brakes, power steering, hard top & hard doors (per vehicle gross weight) tilt steering wheel, big brake package with large rotars & drums, T18 Trans with low 6.4 granny gear, Dana 20 transfer, Dana 30 front axle, Dana 44HD rear axle with 3.73 gears. True Trac ft & rear.
I was around jeeps in the 70's and drove a 1973 Jeep Truck. My family had 4 jeeps at the time. We also joined a jeep club back then too. So about 6 years ago looked for a Jeep CJ and found the vehicle above.
I would guess at 60 mph if you had a car with correct odometer to get to 60 or 65... I will guess your engine rpm is 2300. You are close... I did not look up the finnal gear on Transmission but they are usually 1:1
If she is puffing a bit with unkowns... Do a compression test on a at operational temp engine and record your results per cylinder. Also look at the plugs and record what they look like. Both the compression and plugs will tell you health of engine.
Haven't done a compression test yet. Plugs were rich but I've made some changes since then. You nailed it with the rpm range, don't have a tach but that's what I was thinking. I'm going to start with the team rush upgrades and start measuring gas for for miles and see what I have. I live in the mountains and even a suggestion of bad weather will have me driving the jeep 40 miles to work, so you can imagine why I'm asking this.
1978 CJ7
Silver paint with black hard top on 33" radials & eagle alumium rims. Good looking ride and have done lots of work to make it look and run great.
Stock equipment is 258 carb, power brakes, power steering, hard top & hard doors (per vehicle gross weight) tilt steering wheel, big brake package with large rotars & drums, T18 Trans with low 6.4 granny gear, Dana 20 transfer, Dana 30 front axle, Dana 44HD rear axle with 3.73 gears. True Trac ft & rear.
I was around jeeps in the 70's and drove a 1973 Jeep Truck. My family had 4 jeeps at the time. We also joined a jeep club back then too. So about 6 years ago looked for a Jeep CJ and found the vehicle above.
