Thoughts on engine build

94 4.0 5 speed, stock gears, 2in lift, 30/ 9.5 tires.
lots of blowby out the dip stick tube, low vacuum and low compression on one cylinder(higher with wet test). Got a nice tap tap tap in the bottom.

So I'm going to do full rebuild. Thinking 20-30 bore, chyr HP head gasket, good 3 angle grind on valves, all the normal machine work, rods, crank,head, etc. Going to put in a larger cat back exhaust, dual elect fans nad ugrade some elect. while I got it down. Been thinking about a small cam to bring the power lower in the rpm. (for when I'm climbing those hills with the boat it drops into the power range instead of out of it)

This will be my first 4.0 build so any input would be great.

Sounds like a solid basic rebuild so far. I think you can't go wrong with a mild cam and a little head porting from what I've seen in other builds. Bump the compression up a little bit to go with the cam and smooth out the chambers to reduce hot spots.

A little concerned about bumping up the compression to much. we burn that junk 10% gas in the winter here. And I'm to cheap to by the good stuff.

I would just talk to whoever makes the cam you want to use. They will suggest a static compression ratio that will work best with the cam. Generally, a larger cam will work better with a higher static ratio. But, your dynamic compression ratio won't be increasing the same amount because of the longer duration and more overlap in your valve timing. So, you may be able to run 9.2:1 compression on 87 octane gas (just pulling numbers out of my butt here for an example).

In my experience with building up the Jeep 4.0, I recommend that you upgrade your cooling system too. Like your radiator and maybe a high flow water pump. Just to help keep things cool. Good luck!

Been thinking about a bigger rad and putting my old one in the wifes renix to upgrade to an open system.