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Swap a 4.0L in for your 258

Since my motor was from a Cherokee, I decided not to run a mechanical fan. I have a massive thermostatically controlled electric fan mounted to the front of my radiator. It keeps the engine very cool and I have the option to go back and add a mechanical fan if I feel it is necessary later.

The O2 sensor needs to be installed in the exhaust and the new header connected to your existing exhaust. This cost me $30 at the local muffler shop.

Cole FordAir Intake
Since the Cherokee air intake would obviously not fit in my Wrangler I chose to use a Turbo City Rock-It tube. It looks cool and sounds like a jet engine when you get on the gas hard. I do not know if it gave any performance difference since I do not know what it drove like with out it.

It is possible to use the 258 starter with the 4.0L engine. I would suggest that you get a 4.0L starter. I kept my 258 started and I had to shim it away form the bell housing to make it work. It works great but it did complicate the wiring just a bit since the 4.0L starter is a different set up than the 258.

I had to upgrade to a newer Jeep tachometer to get it to work with my new engine.

Gas tank/pump
You will need a high pressure fuel pump. It is possible to use an inline pump. I found it was more cost effective for me to buy a tank with a pump in it from a newer Jeep. Make sure to use steel braided high-pressure fuel line anywhere you have to use flexible line.



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