Desertdave

I screwed up royal, I bought a builder off a guy in Phoenix to rebuild while I still drive my jeep back and forth to work. I just got the head back yesterday from the head shop and did some research on the casting numbers. Turns out I have a 1990, 2686 head which is a renix motor. I have a 93 sport HO motor, which I need a 7120 head. I can dump the head on craigslist and get my money back, but what about the block? Is there any real difference in the Renix block and an HO block?

cruiser54

You're fine. Don't really need to swap heads for that matter.

Desertdave

You can run a Renix motor in a newer Cherokee? What about all the sensor hookups?

I did notice there is 2 sensors coming out of the block on the drivers side near the motor mount bracket that is not on my 93 HO motor.

cruiser54

Yes, you can. The Renix has a sensor threaded into the bock near the oil pan. Knock sensor. You wouldn't use it. Nor would you use the one part way up the block. The coolant temp sensor. Yours is in the thermostat housing.

HOs are not magic or anything. Minoe differences. The whole 8 horsepower they made over the Renix was due to exhaust manifold design, 58mm throttle body vs 52mm, and intake port differences. And, the estra 8 HP they made was in the upper RPM range. Made not one bit more torque.

Desertdave

So all my sensors from the 93 will bolt on to the 90, like the TPS, CPS and the like?

cruiser54

If you use your manifolds, dizzy, and flexplate.

Desertdave

Thanks for the great info, which intake/exhaust gasket would you recommend I use if I put the 93 intake on the Renix head. I noticed they are different.

cruiser54

Always use the gasket that matches the intake manifold.