Jeep Grand Cherokee Forum banner

1 - 7 of 7 Posts

·
Registered
93&97 ZJ 5.2 Limited AWD 97 ZJ 4.0 Laredo Select Trac
Joined
·
3 Posts
Discussion Starter #1
So I have a 1993 ZJ limited that I’m going to be modifying but I’m running into a few speed bumps in deciding the direction I want to take it.
I plan on lifting 3.5-4” and I already have most all of that figured out by watching Matt on bleepinjeep over at the YouTube’s. Of course I’ll be doing some body trimming and bumpers, just have to get loaded up and the last few things necessary in the shop to get it done.
Furthering, the 280k stock 5.2 is finally suffering from enough blow by and internal leaks to cough oil out of the tail pipe. She’s live her life and it’s time to do a heart transplant, now a disclaimer I am not very forum savvy and I have tried to search for what I am looking for to no avail. So my biggest question for y’all, can anyone link a thread for me to a write up about swapping to a 5.9 from the 5.2... otherwise tell me why I should stay with the 5.2
 

·
Registered
Joined
·
37 Posts
Physically 5.7 & 5.2 identical but 5.7 external balance, at least LA motors were. There are aftermarket flex plates available.
ECU fuel mapping might be a problem.
 

·
Registered
Joined
·
674 Posts
5.9 came in the 98 models but they were often plagued with overheating issues. Easy to spot one as they have louver vents on hood.
if you can solve the heat issue I’d definitely do it. Been out of the game for a long while so don’t remember other issues. I’m sure a few here have done it or old fashion google.
 

·
Registered
93&97 ZJ 5.2 Limited AWD 97 ZJ 4.0 Laredo Select Trac
Joined
·
3 Posts
Discussion Starter #4
I have the heat issue solve, as the 5.2 had similar issues with holding to much heat in the bay as well. A couple of well placed louvers and a new max cooling system set from the parts store and I’m running about 180 with a 195 thermostat. My biggest question is the fueling and such, a weekend experiment with 26.5 injectors from a Dodge Ram resulted in a very p.o.’d Jeep computer... I’ve heard rumors from older car guys and a glimpse of it being mentioned on other sources that a computer from a Dodge Ram truck would allow this swap due to this Jeep being built with the 5.2/46RH combo. The only problem is I have no solid leads on a positive answer to pursue this and know I’m not running for a dead end. Any help is appreciated.
 

·
Registered
Joined
·
87 Posts
Is there any good reason to do a 5.9 swap?
Anytime you go from one engine to a different one, you will have a ton of research, experimentation, trial and error, and unexpected expenses in both time and money. The vehicle will need either a tune or compatible ECU.
All of the issues you run into will certainly have solutions, even if the easiest solution is to find a complete donor vehicle.
The problem is after all that trouble and expense you will still have a thirty year old Jeep with an outdated motor that doesnt offer any significant performance benefits except maybe burning gasoline faster.
If this is a vehicle you feel is worth saving, than the simplest, cheapest, and historically correct solution is to use the right motor.
If you wanted a better motor while keeping a reasonable budget, a 4.7 would be a good solution because complete donor vehicles are a dime a dozen.
If you wanted to "hot-rod" it up, a modern Hemi would be a better solution than a 5.9. You would still probably need a complete donor vehicle, but they aren't that hard to come by.
 

·
Registered
Joined
·
79 Posts
The big item is the computer that the 5.9 will need. Are going to swap the interior out too?
 

·
Registered
93&97 ZJ 5.2 Limited AWD 97 ZJ 4.0 Laredo Select Trac
Joined
·
3 Posts
Discussion Starter #7
I have another 97 limited that body rot has destroyed that I plan to swap in but not the dash, I don’t want to OBD2 swap I would rather refrain from that much rewiring.
 
1 - 7 of 7 Posts
Top