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Renix Header suggestions?


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Obviously, they are getting harder and harder to come by. Motion Offroad is sold out of the 88743, and so is pretty much everybody else. Some places are listing the 88745 as being compatible, but I see it as being listed for the HO-only 4.0s on many sites.

 

1, Is there a cost-effective (under $250) alternative to the Walker/Dynomax Blackjack 88743?

2, Does the 88745 work on the Renix motors?

3, Am I just screwed?

 

Thanks!

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If the 88743 is what I remember, it sure looked like a Pacesetter, who also had a Renix header.

The PaceSetter is around $250-260, shipped. The 88743 is out of stock pretty much everywhere.

 

I can find the 88745, which Summit Racing said would fit the 87+ 4.0s, but then why have 2 part numbers?

 

Also, I used to see Renix-compatible no-name headers on eBay (about $140, shipped), but now they list the full 4.0L year-range (say, 87-01) on some and 91+ on others. I don;t want to buy one of the 87-01 models and have it not fit, but the application guides list them as working on the Renix (I have an '88).

 

I am looking here for technical guidance from anyone who is in the know.

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Technically they will fit but it is not the most ideal way of doing things. The intake and exhaust holes on the heads of the Renix and Chrysler don't line up perfectly with each other (I think the Renix was offset higher). I have known people that have done engine swaps to the newer Chrysler engines and left their stock intake/exhaust manifolds on it and know of a person that did it the other way with no ill effects.

 

The only real issue that you would run into is maybe with the downpipe of the exhaust not lining up perfectly. If that is the issue, you should be able to get a downpipe from a '91+ and it should fit right on there. If I remember, I can check on the differences in length tonight between the two. I'm currently working on putting a new engine in an '88 Wagoneer and have a '91-'95 exhaust manifold kicking around that I can line up next to it.

 

If no one else chimes in by tonight and I don't get a chance to measure, send me a PM to remind me.

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Technically they will fit but it is not the most ideal way of doing things. The intake and exhaust holes on the heads of the Renix and Chrysler don't line up perfectly with each other (I think the Renix was offset higher). I have known people that have done engine swaps to the newer Chrysler engines and left their stock intake/exhaust manifolds on it and know of a person that did it the other way with no ill effects.

 

The only real issue that you would run into is maybe with the downpipe of the exhaust not lining up perfectly. If that is the issue, you should be able to get a downpipe from a '91+ and it should fit right on there. If I remember, I can check on the differences in length tonight between the two. I'm currently working on putting a new engine in an '88 Wagoneer and have a '91-'95 exhaust manifold kicking around that I can line up next to it.

 

If no one else chimes in by tonight and I don't get a chance to measure, send me a PM to remind me.

That would be awesome. I don't mind buying the more expensive one if it is the only one that will work, but if I can save $100+, that would be good. I only drive the truck a few hundred miles a year for now.

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Long time no see buddy! How have you been?

It HAS been a while. I have been lurking on here, but I had bought an '88 BMW 325 that I was building to take to the track. That was consuming a lot of resources (time and money), so I sold it when I finally got it finished. I bought a new daily driver and finally have the time to get back to playing with the COmanche. I have really bad valve noise, and I am thinking that it is probably a cracked exhaust manifold or the mid/down pipe that connects to the cat. I already need a new muffler as well, so I might as well do all of the exhaust at once and be done with it, if possible.

 

The only thing that I have done for the truck in the last year is to buy one of the remaining hitches that fit it and to start prepping it to be repainted.

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Sorry about the delay, took me a few days to get out there.

 

The difference between the manifolds is the angle it connects to the downpipe. The Renix manifolds flange is straight down while the Chrysler manifolds flange is angled back about 45 degrees.

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Sorry about the delay, took me a few days to get out there.

 

The difference between the manifolds is the angle it connects to the downpipe. The Renix manifolds flange is straight down while the Chrysler manifolds flange is angled back about 45 degrees.

Thanks for the follow-up. I have a 15% off and free shipping code for JC Whitney, so I can pick up the Pacesetter that is specific to the Renix for about $220 shipped, so I might go that route.

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Is there any difference between XJ headers and MJ headers?

 

Morris 4x4 has a header for the 4.0L, part number PST-701191, but it states it's for the XJ, doesn't mention the MJ.

 

I have a 10% coupon for Morris 4x4 at my website, but I have a feeling that JC Whitney will still probably be a better deal.

 

Another question...whats the difference between a header and an exhaust manifold?

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XJ and MJ headers are the same. A header and exhaust manifold are the same thing, for all intents and purposes.

 

If thats the case, Advance Auto has manifolds for less than $200 last I checked. Part 674-170 fits an '88 4.0L.

 

Once again, discount codes on my website.

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whats wrong with the dynomax header?

Seems like it is out of stock everywhere, at least in the Renix fitment. The H.O. version is pretty prevalent, but does not match right up with the surrounding parts on the Renix.

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Is there any difference between XJ headers and MJ headers?

 

Same

 

Another question...whats the difference between a header and an exhaust manifold?

 

Headers are (at least in theory) more free-flowing, which should free up more HP. Manifolds are typically not engineered for the type of flow that headers are supposed to provide.

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