[greenmachine99]

Ive been trying to find a 5.2 donor for awhile. I thought I'd broaden the search and start looking for 5.9's also. Either would replace my 4.0 in my 99 tj. My question about the 5.9 is arent they externally balanced and the 5.2 is internally? Point being everything I find is auto. I'm going to be switching it over to manual, and I assume the 5.9 would be balanced at the fly wheel. Rather than go through all that with taking the motor to a machine shop and pay for all the shop time, do I just want to stick with a 5.2? To me its not worth the extra power to do all that. So is my assumption right or can I just take the flex plate off, throw on a fly wheel and call it good on the 5.9 like I could on the 5.2?

[Texas ZJ1]

I did the swap from 5.2 to 5.9 but, this is the info I used.


What is needed for a 5.2 -> 5.9 swap?

93-95 ZJ V8
5.9 flexplate
5.9 harmonic balancer
5.9 driver's side motor mount
torque converter from 96-98 V8

96-98 ZJ V8
5.9 flexplate
5.9 harmonic balancer
5.9 driver's side motor mount

Notes
You can use a spacer or washers and make the 5.2 motor mount work.

You can oval out one of the holes on the 5.9 flexplate and make a 93-95 torque converter work.

Late '95 ZJs may not need the torque converter because some of them came with '96 flexplate and torque converter.

A complete motor from a 98 5.9 ZJ will bolt right into a 96-98 V8 ZJ. Because of OBD1 and EGR, it will not bolt into a 93-95 ZJ. You will need to use the old throttle body and sensors. If you have emissions testing, you will need to use the old intake manifold and the passenger's side exhaust manifold to maintain the EGR system.

The upside to swapping a 5.9 into a 93-95 V8 ZJ is the 46RH transmission, which is stronger than the 44RE used in the 96-98s.

Hunter

[greenmachine99]

So all I need is a harmonic balancer? It'll be a complete motor and will already have it on.

Sent from my iPhone while I shouldn't be on my iPhone.

[ratmonkey]

flex plate/flywheel and the harmonic balancer are externally weighted.
it's universal though.

[greenmachine99]

Originally Posted by ratmonkey

flex plate/flywheel and the harmonic balancer are externally weighted.
it's universal though.

Universal as in just order a flywheel from rock auto? Or do I need to have it balanced?

Sent from my iPhone while I shouldn't be on my iPhone.

[Tamatacan]

Buy an external balance from Mopar. It should work on a stock street motor.
http://www.summitracing.com/parts/DCC-4529110/
Bob

[greenmachine99]

Originally Posted by Tamatacan

Buy an external balance from Mopar. It should work on a stock street motor.
http://www.summitracing.com/parts/DCC-4529110/
Bob

Isn't any flywheel for the 5.9 made to balance it? That seems kind of steep.

Sent from my iPhone while I shouldn't be on my iPhone.

[ratmonkey]

Originally Posted by greenmachine99

Isn't any flywheel for the 5.9 made to balance it? That seems kind of steep.

Sent from my iPhone while I shouldn't be on my iPhone.

that's a pretty normal price for a magnum external balance flywheel.

http://www.summitracing.com/search/P...0/?Ns=Rank|Asc

[Tamatacan]

Well if you have a good balance shop you can have them take the 360 stock flex plate and balance it to your flywheel on an double ended arbor. We use to do it. Some shops can't but it works. Most 360 autos had the weight on the torque converter. And yes your right. Most any 360 flywheel will have enough imbalance to spin with your crank. It won't be right on but most likely close.

[SunDevilJeeper]

Originally Posted by ratmonkey

that's a pretty normal price for a magnum external balance flywheel.

Mopar: You gotta pay to play.