TUPY head on 01 Cherokee

[KCullison]

I searched but didn’t find what I was looking for. I probably used the wrong keywords. Anyway, I have a 01 Cherokee with the 0331 head (non-TUPY). I have a 99 XJ ECU to swap in to eliminate the 2 pre-cats and O2 sensors. I was wondering if using the TUPY head from a 06 TJ with the factory 01 XJ manifolds and a federal emissions down pipe would work, as well as plugging the extra O2 sensor holes. Or would it be better to use the 0630 head with a 99 manifold or header? The Jeep only has 78k miles on it but I want to get out in front of any issues down the road while parts are relatively still easy to come by.

I live in NC and the Jeep is over 20 years old so it’s only subject to a safety inspection. I’ve had vehicles without converters in the past and haven’t had any issues passing. I figured that the exhaust is good enough for a 99 than it should be good enough for my 01. It’s not like it won’t have 1 converter still on it. Thanks in advance.

 

[RCP Phx]

I run the 0630 head on my 2000 mainly because I could use the Banks Revolver header which is what Russ did the port matching to mate up with! You may need the earlier PCM to compensate for the loss of O2 sensors.

 

[KCullison]

I was thinking that the TUPY head might be the easier swap since it probably already has the bracket for the coil packs, but I’m not afraid to fab something up. I will definitely be using the 99 ECU. Just want the best bang for the buck and not have to do it twice.

 

[75SV1]

The 2000 Fed XJ dose not have the Pre-Cats. Also, K-Suspension has a Kit for the Viper Coil upgrade. I did replace the cast iron exhaust manifold with an after market header, JBA. Its the 'compact' ones they sell for TJs. It sort of makes the 2000 Fed into a Tri-Y header.

 

[RCP Phx]

I run the 0630 head on my 2000 mainly because I could use the Banks Revolver header which is what Russ did the port matching to mate up with! You may need the earlier PCM to compensate for the loss of O2 sensors.

I used a tupy 0331 head that Russ made into a 0630 so it had the coil rail mounts! I did install a "Screamin Demon" coil to replace the OEM rail.
https://naxja.org/forum/showthread.php?t=1148702

 

[75SV1]

Also, don't forget about the wiring harness from the ECM. It will be different for a '99, a 2000 Fed and a 2000 Cali-2001.

 

[IslanderOffRoad]

The viper coil is the best way to avoid worrying about the coil rail. I did it when I put a TUPY head on my 01, not because I needed to, but because while I was at it I figured why not.

I kept the precats though.

 

[chris420]

I have a Tupy head on my 00 XJ no pre cats from the factory it’s an Arizona vehicle. No check engine lights and passes Smog. Stock ECU. Couldn’t you just weld two sensor bungs in line and eliminate the pre cats?

 

[IslanderOffRoad]

I have a Tupy head on my 00 XJ no pre cats from the factory it’s an Arizona vehicle. No check engine lights and passes Smog. Stock ECU. Couldn’t you just weld two sensor bungs in line and eliminate the pre cats?

Not legally if it came with them.

 

[chris420]

That’s a bummer. Do they check the 02 sensors when they do a smog check? I know the shop I go to did go under it once to look around and asked a bunch of ??. How could they prove that the vehicle came with pre cats? I guess you could be taking a chance but I wouldn’t think they could prove anything as long as it passes the computer test and emotions test.

 

[IslanderOffRoad]

That’s a bummer. Do they check the 02 sensors when they do a smog check? I know the shop I go to did go under it once to look around and asked a bunch of ??. How could they prove that the vehicle came with pre cats? I guess you could be taking a chance but I wouldn’t think they could prove anything as long as it passes the computer test and emotions test.

All 2001's came with them whether federal or CA emissions so their system should be telling them to look for them.

Also as I learned doing mine a few year back the third cat under the Jeep is just along for the ride so there's no sensor after it. Likely to throw a code and thus fail because the Jeep isnt seeing any change before/after the measured cats. I suppose you could try to move the sensors to after the rear cat like on an earlier model.

For me just replacing the precats made a world of difference. I'd rather not worry about whether what I did passing emissions if I ever relocate for work somewhere thats more stringent so it is what it is.

 

[75SV1]

I have a Tupy head on my 00 XJ no pre cats from the factory it’s an Arizona vehicle. No check engine lights and passes Smog. Stock ECU. Couldn’t you just weld two sensor bungs in line and eliminate the pre cats?

The 2000 XJ came in two version in the US. The Federal with no precats, and the Cali with the pre cats. You would not need to 'add' pre-cats if you swapped in another head.