4.0L Header vs Manifold
10-04-2011, 01:01 PM
#20
CF Veteran
Join Date: Oct 2009
Location: Fauquier County, Virginia
Posts: 2,867
Likes: 0
Received 15 Likes
on
13 Posts
Year: 1991
Model: Cherokee
Engine: I-6 4.0 HO
Whoever wanted the installed pics, these come from my how to: https://www.cherokeeforum.com/f51/je...91-98-a-80445/
This is where they crack most of the time. The pic of the sixth runner is where mine cracked the worst...almost all the way around.
As mentioned, the bottom bolts suck getting too, and BE SURE to use high temp thread lock on the flange bolts... trust me. I would know, and let me tell you that tightening those bolts by yourself even after pulling the airbox, brake booster hose, fuel line bracket, and one or two other things it is still a dog to do, especially alone. Thank God for multiple extensions and swivel joints.
This is where they crack most of the time. The pic of the sixth runner is where mine cracked the worst...almost all the way around.
As mentioned, the bottom bolts suck getting too, and BE SURE to use high temp thread lock on the flange bolts... trust me. I would know, and let me tell you that tightening those bolts by yourself even after pulling the airbox, brake booster hose, fuel line bracket, and one or two other things it is still a dog to do, especially alone. Thank God for multiple extensions and swivel joints.
10-04-2011, 01:04 PM
#21
CF Veteran
Join Date: Oct 2009
Location: Fauquier County, Virginia
Posts: 2,867
Likes: 0
Received 15 Likes
on
13 Posts
Year: 1991
Model: Cherokee
Engine: I-6 4.0 HO
To date, I don't think any Renix headers are made, and I think this is mainly due to the fact that the Renix head has different ports compared to 91+ 4.0's, and since the majority of people go after OBD I or II vehicles, I guess Renix headers just didn't have enough demand. Not dissing Renix or anything, just saying what I think caused the lack of a header. I could easily be wrong, and hell there could even be one hiding out there somewhere.
10-04-2011, 01:05 PM
#22
CF Veteran
Join Date: Sep 2010
Location: Milwaukee, WI
Posts: 21,168
Likes: 0
Received 5 Likes
on
5 Posts
Year: 1987
Engine: Check
To date, I don't think any Renix headers are made, and I think this is mainly due to the fact that the Renix head has different ports compared to 91+ 4.0's, and since the majority of people go after OBD I or II vehicles, I guess Renix headers just didn't have enough demand. Not dissing Renix or anything, just saying what I think caused the lack of a header. I could easily be wrong, and hell there could even be one hiding out there somewhere.
No, sir, they have been made.
10-04-2011, 01:45 PM
#25
CF Veteran
Join Date: Dec 2010
Location: Finger Lakes Region NY
Posts: 1,234
Likes: 0
Received 1 Like
on
1 Post
Year: 1990
Model: Cherokee
Engine: 4.o
i just might have a set of headers on mine according those photos. i could be wrong. i'm gonna go snap some pics and do some research.
10-04-2011, 02:12 PM
#26
Seasoned Member
Join Date: Oct 2009
Location: Portland, Oregon
Posts: 414
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1991
Model: Cherokee
Engine: 4.0L
I recently installed an APN header and I like it. I noticed a slight bit more power, nothing major, and slightly deeper, smoother exhaust note. The header is very beefy and well made. It's true that a couple of the bolts are very hard to get to and I'd recommend picking up one of those sockets with the built in u-joint. A traditional u-joint adapter will not work, there is just not enough room behind the primary tubes. Your other option would be to just use a wrench on those bolts rather than a socket, which is what I had to do as I didn't have the fancy swivel socket. A couple different size extensions would also be handy in reaching the bottom bolts.
As far as I know the only company currently making a Renix header is Pacesetter. You can buy they from Summit, they are pricey, about $250. Dynomax used to make one but it is now out of production, same with a couple other companies I believe.
As far as I know the only company currently making a Renix header is Pacesetter. You can buy they from Summit, they are pricey, about $250. Dynomax used to make one but it is now out of production, same with a couple other companies I believe.
10-05-2011, 12:49 AM
#29
Newbie
Join Date: Aug 2011
Location: The Ozarks
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Year: 89
Model: Cherokee
Engine: 4.0L
pacemaker makes headers for the renix i have seen them on a site or two if you look they are still available i think they were about 275
10-21-2011, 04:14 PM
#30
Senior Member
Thread Starter
Join Date: Apr 2010
Location: Marshall, WI
Posts: 720
Likes: 0
Received 1 Like
on
1 Post
Year: 1994
Model: Cherokee
Engine: 4.0L i6
Are aftermarket headers normally the same length as stock manifolds are? Basically would I need to modify the exhaust pipe to compensate for any difference in length? Wondering if I should wait until I get my new exhaust before swapping this out.