cam swap and ignition upgrade ?'s on 89 renix 4.0

[big66440]

I'm looking to do a few upgrades on my stock 4.0 so far I've came up with a cam swap to a comp cams high energy piece along with their roller timing set as well as summit's own high performance ignition box,coil and taylor's thundervolt wires.I noticed on the comp website that the cam is advertised for use on 84-97 4.0's but is NOT for use with fuel injection,if their cams aren't compatible who makes one that is? I'm looking for as much low end as possible along with maybe some improved mileage,also will the summit ignition box and upgrades work with my year model comanche? anyone run after market hi-po ignition systems?

[Eagle]

Considering that the 4.0L engine was never available without fuel injection, I think you should call the cam company and ask what they mean. Might be a misprint.

[jeepcoma]

I threw a spare MSD 6A on my '91 HO. I didn't expect much out of it, but I was hoping for a bit easier starting in the winter and easier restarts if it stalls while cold (seems like it would flood trying to restart while in warm-up mode, even with brand new plugs/cap/rotor). Maybe a bit extra gas mileage on the highway. That being said, I was shocked (no pun intended) by the improved quality of idle and low-end responsiveness. It also seem much more resistant to stalling (I didn't do any intentional pre/post testing to specifically check this), to the point that it seems like it will recover from impossibly low RPMs and just keep on going. All in all I was pleasently surprised. Would I go out and spend $300 on a new MSD unit? Nope. Would I recommending picking up a used one for $50-$75, or an inexpensive unit from another manufacturer? Sure!