mileshigh
Well-Known Member
- Joined
- May 2, 2005
- Location
- Charlotte NC
ok i have a 1990 xj with the renix engine, does anyone know what all is involved with swaping in a 1999 H.O. 4.0l engine
4.0l upgrade question
- Thread starter mileshigh
- Start date
Falko
Well-Known Member
- Joined
- Mar 20, 2005
- Location
- Winston-Salem
Do you want to put in just the engine? or all of the associated OBDII stuff with it?
mileshigh
Well-Known Member
- Joined
- May 2, 2005
- Location
- Charlotte NC
well i want to put the engine in and since my jeep doesnt have to pass inspection anymore that stuff is not required but i think it the smog stuff has to be there visually
Falko
Well-Known Member
- Joined
- Mar 20, 2005
- Location
- Winston-Salem
The bottom end is for all intents and purposes the same, the one thing that you will have to check is the presence/absence of a bung for the knock sensor in the 99 block. I am not sure when the casting was changed, but i do know what the bung remained in blocks long after the demise of the renix injection.
As for the top end, the port design changed from renix to H.O. years (the ports became taller) so the older intake wont line up *correctly* with the newer head ports. If you use the newer intake manifold, then there will be no port for an EGR valve (which is useless garbage anyway) but if your shop is going to check for smog equipment...
Also the older TB won't bolt up to the new intake and sensor swapping between them is a bit tricky. You could machine a spacer plate if you went this route.
As for the top end, the port design changed from renix to H.O. years (the ports became taller) so the older intake wont line up *correctly* with the newer head ports. If you use the newer intake manifold, then there will be no port for an EGR valve (which is useless garbage anyway) but if your shop is going to check for smog equipment...
Also the older TB won't bolt up to the new intake and sensor swapping between them is a bit tricky. You could machine a spacer plate if you went this route.
I installed a 94 4.0 in my 86 mj. It had the renix 2.5. I just pulled the complete engine and wiring harness left it all attached the best i could. I also switched the interior wiring harness becouse so much was different. It was easier than figuring out everwire. Also you will need a factory service manual for the 99 xj. hope this helps.