Exhuast Manifold Question

[M1A1TankerTom]

I need a new exhaust manifold on my 89 Renix 4.0. I have searched the board up and down and have seen a lot of different answers but what exactly is stoping a 92 and up manifold/header from fitting a 91 and below engine? Is it possible to fit a 92 and up manifold on a renix motor and if so how?

 

The reason I want to know is simply becuase you can buy a 92 up APN header for around the same price if not cheaper than the price of a new renix stock manifold.

[freakjeep93]

i think the 92 and up were different as thats when the HO motors started. i think it was different bolt patterns or something.....

[Geonovast]

You're a little mixed up on your years. 91 was the first year for the HO, not 92.

 

As for the differences on the head, I believe the ports are different for the intakes, not the exhaust.

 

Renix manifolds have the O2 sensor on the... HO ones do not. It's in the downpipe.

[freakjeep93]

opps as i said i though not knew. and i meant to say 91 but i hit the wrong button :dunce:

[M1A1TankerTom]

so if the exhaust ports are the same then wouldnt that mean that a 91 and newer manifold would fit on a renix motor?

[HellBent]

so if the exhaust ports are the same then wouldnt that mean that a 91 and newer manifold would fit on a renix motor?

 

 

it will bolt up just fine. the biggest issue would be the lack of an egr bung, which may or may not matter-depending on the emissions testing for your state. also it will be lacking an o2 sensor bung, and the current downpipe will have to be modified(IIRC). not really that big a deal, and the o.e. renix manifold is a not a very hi-po piece anyway...

 

edit: just noticed you're in CA as well, wouldn't be that big a deal to weld in a bung to keep the egr. if i didn't already have a borla renix header, i'd be doing just that.

[M1A1TankerTom]

ok cool, so an HO header will work on a Renix motor you just have to have an EGR and O2 sensor bung welded in. Thats what I needed to know, I'm gonna pick up a APN header for a HO motor and give this a shot. Thanks guys.

[jimoshel]

Has anyone ever took a grinder and ported one these ex,in manifolds so they would fit?

[comanche09]

I believe if you go with a HO exhaust manifold, the downpipe is also different vs. renix. You could get around that with any good muffler shops or if you have a welder. Or get a HO downpipe.

 

I thought there was Renix intake manifold clearance issues with the HO exhaust manifold as well... :???:

[jpdocdave]

i did some research, not a ton when i did mine, i can't remember much but i do know i chose not to use an ho manifold on my renix.

[Ironwolf]

I have always used the pacesetter brand header for the older 4.0. From time to time you will have to drill out one of the mounts but other than that you should be fine. It also comes in a ceramic coating now.