I developed an exhaust leak, and found a cracked manifold. Anyone install a header on a 3.5L????

 

This is the one I'm looking at. I5 Colorado/Canyon Stock Replacement Header

First I'm getting the ported throttle body and then the headers. Although I hear some of the pick up guys just knock the cat out of the stock exhaust and get 10hp. But that wont work for you with a busted exhaust. I think these headers will make more power and look better to.

 

that is the one I am looking at. The problem is I can't find a used manifold, and a new one costs 450 bucks. I might as well buy the header for the same price

 

Man, I looked all over for headers for my Alpha and couldn't find any. Customs would have to be fabricated.

 

Well, I would sell you mine for $200 OBO. Let me know, If you want it I will order the header now. It does take several weeks for delivery.

 

I'm just gonna spend the money on the header

 

any trouble with o2 sensors??

 

still doing the research, and then I will order it

 

I am interested in buying those headers too! Let me know how you like them after install

 

There have been people that have messed with a header for the I5s. One I know of put the OEM back on after more than a year. Many more of the Colorado guys have done it.

Without the mini/pup cat in the exhaust manifold (like OEM or the MagnaFlow replacement) you will probably have issues from the downstream O2 sensor. Depends if you want fuel economy and no CEL, or performance with a CEL and less than optimal fuel economy.

The mechanical work around is to use an O2 sensor extender in the downstream position (basically it is a male & female threaded bung about 3/4" long that screws into the O2 sensor location, and then the sensor screws into it). This will pull the sensor more out of the flow of the exhaust and trick it to think there is less burned fuel present. If you have a local and competent tuner, they may be able to patch this problem through the PCM without the extender and/or by using a different O2 sensor?