Re: six cylinder in 79 Cherokee
if its a 258, you can do what I did. Slapped on a 92 4.0 HO head, toss that old dist and put in a C&^%y HEI dizzy. get the right adapter and put a motorcraft 2100 2bbl carb (found a most Jeep 360s)on the intake. Oh yea, you would also need to the the ehxaust maniforld for the 4.0 head also. Do not get a 4.0 head from 90 or older, must be 91 or newer. There are some things that need to be done to the head but you can have them done for under 250.00
Before I did all that I to would get dogged down on easy inclines, even on the freeways, after the upgrades, only time I down shift now is if I am off-road and meet a REAL steep incline.