2.8 Or 2.5 Which Would You Choose

[Eagle]

Basic comparison:

 

The 2.8L (as used in the XJ and MJ) was rated by Jeep at 115 HP at 4,800 RPM, and 145 ft-lbs of torque at 2,400 RPM.

 

The 2.5L Carbureted version (used in the 84 & 85 XJs) was rated at 105 HP at 5,000 RPM and 132 ft-lbs of torque at 2,800 RPM. (A few less horses, and almost equal torque.)

 

The 2.5L TBI as used in the 86 - 90 MJs and XJs produced 117 HP at 5,000 RPM and 135 ft-lbs of torque at 3,500 RPM in 1986. In 1987 that was increased to 121 HP at 5,250 RPM and 141 ft-lbs of torque at 3,250 RPM. That's MORE horsepower than the 2.8L, and almost as much torque -- with significantly better gas mileage.

 

Then we get to the "HO" (multi-port) version of the 2.5L, used in the 91 & 92 MJ. That produced 130 HP at 5,250 RPM and 150 ft-lbs of torque at 3,250 RPM.

 

As I posted above, IMHO the 2.5L wins hands down.

[onlyinajeep726]

:agree: 100%

[Htchevyii]

You can buy a GM 3.4 crate motor to replace the 2.8. It might be OK 160 HP

http://www.summitracing.com/parts/nal-12363230/overview/

[mpace6a]

You can buy a GM 3.4 crate motor to replace the 2.8. It might be OK 160 HP

http://www.summitracing.com/parts/nal-12363230/overview/

Why would anyone spend $2200 plus shipping for that, when you could buy a parts cherokee, ram, zj, mercedes, whatever, for that price, part out the vehicle, keep the driveline, and use the money from parting it out to sort out odds and ends for more power and/or effeciency?

[TheDirtyJeep401]

Supercharged Buick 3800 (I think) lol

 

Id prefer the 2.5. You get good gas mileage, torque and some power. I live in MO and I can drive up a hill in 4th gear just fine with out down shifting. They are durable and a very easy engine to work on. They are great engines. 

[gogmorgo]

Yeah, looks like a FWD 3800 that was spun 90 degrees... Getting that supercharger to breath must have been a b*@$£ and then some...