I recently detonated a piston in my 5.9L Grand Cherokee. Am looking to rebuild because the block was not scarred much. My dad is the mechanic but is having trouble finding the parts to rebuild. Is the 360 in the 98 Grand Cherokee the same one used in Dodge pick-ups, dakotas and Durangos? Where is the best place to find complete rebuild kits? Am looking to kick the HP up to between 325 and 350 but want to maintain a good low end torque for towing on steep inclines. Will only be towing about 5,000 lbs and currently have 3.73 gears. Before actually towing am thinking I will be going to 4.10 gears.

 

My son got a kit from Enginetech. Yours is a Chrysler.
It says 70-91 is 4.080 bore AMC engine.
Double check and confirm part numbers as we had a mix up but they made good
in a timely fashion.
Edit: look up Enginetech go to red catalog then engine search.

 

hughesengines.com they have everything you'll need. yes all the 5.9s are the same. different vehicles may have different cams but thats about it.

 

Here's another place http://www.speedomotive.com/s-13-small-block-mopar.aspx

 

Any 5.9 will work from 94-01(?) as the blocks are the same but as 78doubler said, the cams may be a bit different.

Make sure that your tranny, t-case and axles are up to par with handling that kind of power.

 

When you start comparing numbers price out a long block or used motor from the bone yard. With fuel injection and good rollers these days i have seen many in the 75k mile range that had minimal wear if any. Last one i got was 500 bucks with heads.

Grab a used motor, change the oil pump and timing chain, sell the heads and accessories. Check your heads for cracks when they are off.

Put a cam in it. 212/218 at .5 or 210-220 .5 Change the springs to the Hughes 1110 and retainers, direct fit, no machine work needed and installed height is same to reuse your valve train gear. CHECK push rod length in case cam base circle is smaller as is common with some of the new quick opening ramp lobes..


You will need shorty headers, SCT tuner, and Mopar M1 fuel injected intake.
( your intake will work but wont get you past 4000rpm with any flow.

This combo will give you the occasional tow you want but will rev up past 5000rpm and make this a nice sleeper. The sct will let you change shift points to take advantage of the intake.

 

I kinda like Pk's suggestion.

 

LOL! ME too! Gonna see if I can get the boss to approve it...

j

 

He's right about the wear! I just tore-down a 95,000 mile 2.5 Mitsubishi in a 99 Cirrus and could still see the original cross-hatch in all cylinders! F.I. Rules! No more cylinder-washdown from bad carbs! Pk, I'll be replacing my 263,000 5.2 in my Ram soon. A friend has a 99 5.2 with 99k on it. Was thinking about just putting a Computer friendly RV cam in it and calling it a day. Opinions? Its just a tow vehicle, and snow truck now. Not a daily driver.

 

318 can do well with some mild upgrades. they're a great motor. Biggest problem is the computer. With or without the dreaded "death flash" it wont handle changes in LSA, duration or dramatic lift changes without the SCT tuner. Which sucks cause the heads flow in the area of 210 plus at .5 of lift.

For the "money's no issue" folks..

206 / 212 with .480 lift, hughes 1110 springs and retainers, shorty headers and SCT. Have the cam cut no tighter than 112lsa. I prefer 114 for heavy trucks with a tow option. Leave the TB and intake alone. Set TPS at .78 and "fuel sync to +4. Go one heat range colder in the plug. This will make a huge difference in performance and be very streetable and tow nicely.

I'm like you, since you are swapping blocks the cam swap is easy.

But the cam alone may cause some issues. Some pcms handle them, others don't.

All will handle headers nicely.

 

I had my fuel system cleaned, flushed etc and after 1 month I had the check engine light come on. The computer reads misfire cylinder 3, so I replaced the plugs had the wires and rotor check out fine, plug on cylinder 3 had black build up, more so than any of the other plugs..does anyone have any idea what can be happening? I'm going to replace the ignition coil this wknd and see what happens. It is well taken care of and never misses a service. 115k miles. Also it started to run low on coolant?? and the ac condsensation line is clogged, is there any way these problems could be correlated? thanks for the help!

 

If your coil was bad it wouldn't discriminate between plugs.

Your Dad turns the wrench for a living right? Time to hang over his shoulder for some basics.

Don't change parts. Spend your money on tools and test the parts you already paid for.

Measure resistance in the plug wires. You can do this with the OHM setting. Make sure they aren't crossing each other closely at 90 degrees. Inspect boots and inside terminals.
Check the gap in each plug. And stay with reg plugs. Do not use platinum or anything iridium.
Check the cap for cracks and make sure it sitting off center.
Pull injector 3. Make sure the o ring isnt cracked or leaking.
Swap that injector with one from the even side of the motor.
Reset computer and drive.

Did you recently pull the dizzy? And if so did you reset fuel sync to +0?

 

Figured I would pull up an old thread from the grave. We did the motor swap a couple years ago, got about 13K on motor now. Never set the fuel sync when we installed and I took it to the Jeep dealership and they looked at me like I was crazy when I asked for them to set it. They had never heard of it nor had the mechanic. It has been running nice but how do I go about setting the fuel sync myself?

 

I think if it runs..... It's in Sync.....
If not it would not start and run.... I think you could only have the rotor 180* out... But does not sound like the case here.....
I think that is only a read only PID by design on the OEM? Not 100% sure....
I do know that with something like a "Megasquret" you would have to input the parameters....

 

If the fuel sync wasn't right, it would either not run or stumble. Its something that the computer "self learns" after running for a little bit.

 

So the engine is just going to learn the fuel sync on it's own? It will advance it +4 for the cam not back to factory 0?
I was under the impression I could do it with an old MT2500 scanner but preferred to just get it done at dealer rather than buying another tool. I also read somewhere it could be done with a multimeter but that it could be way off that way.
It runs pretty good but does not idle well. Perhaps sync is set with the SCT?

 

Yes its supposed to "relearn". Not sure how it would take into account the cam though.

I'd ask around locally if anyone has a MT2500 scanner that you could borrow or even "rent". Or someone may be able to reprogram the ECM for you based on the specs of the engine. I know a few people do that with the GM ECMs in the off-road community.

Years ago we had a guy come into the dealership with a stroked 5.9L in a 98 GC asking the same thing and our scanners then couldn't do anything for him. Never heard from him what he did to fine tune it.

 

Gear ratio ? What size tires are on it ??? auto ??

 

Stock gears, 3.73, and it is an automatic. Tires are retreads and I could not see a difference from the 265x70r16 tires I took off.
I suspect I'll know more when I finish installing my data logger. I have bung installed so far.