Head Porting question

Need some advice. I have a 1990 4.0L with 220k on the clock. Motor runs great,good oil pressure,etc. I also have a spare head off of an identical motor that I was considering porting and installing on this motor. Is this a worthwhile project or am I just wasting my time?? Have ported heads in the past with great results but they were on carberated V8's.

I gained about 14hp from my ported/milled head so it's definitely worth doing. Here's my write-up:

http://www.jeep4.0performance.4mg.com/head.html

AFAIK, it's the only write up of a Jeep 4.0 head porting project so it'll help you a lot.

What works on a V-8 works on a I-6...just dont go nutz grinding away the floor of the port on the inside radius to the valve seat..that will kill any other improvements you make...taper the valve guide bosses expecially on the exhaust side...if the valve guides are worn, you can fit SB chevy valves by resizing the guides and adjusting the valvestem lenght to match the OEM..match the intake and exhaust ports to the manifolds..this makes more difference than you would think.

One word of caution...make a poster paper template of the cylinder deck and check it against the head, or more ideally mount the head on the block and scribe the head from below to show the relationship between bore and combustion chamber..if there is core shift in the valve pockets, the large valves (2.02/1.60) may not clear the cylinder bore without oversizing the cylinders...especially if you relieve the shrouding on the valve pockets..