Here's a pic of one on ebay for sale. The exhast manifold is cast into the head...not welded. Hopefully this will answer most questions about headers and etc.

 

anyone who actually looked on acuraautomotiveparts.org would have know that

 

Yeah, it shows up in the Service Manual "drawings" as well. In my opinion, this is a very poor design. I think Acura/Honda seriously missed the boat on this. They should have made use of quality headers like many (most of the more serious performance cars) to up the power output of the engine.

I would bet their reasoning for this has to do with the ULEV rating they wanted for the engine, but I still say that this is a poor design.

 

It would be safe to say that 90%+ of the TL's will never have aftermarket headers put on so the Honda engineers probably stuck to a exhaust design that optimized performance, cost, space, and emmisions. Like almost anything in the world there is always a compromise.

 

To Legend2TL;

I agree with your statement, "It would be safe to say that 90%+ of the TL's will never have aftermarket headers put on", but I wasn't talking about after-market headers installed by the buyer. I was talking about headers installed at build time, by the factory as part of the engine design. A lot of high-performance and other serious factory machines are like this. Mustangs, Corvettes, BMW's, Porsche's, heck, even the 2000 SVT Contour I used to own.

 

You are driving a TL...a 4 door family car, not a V8 Vette....total difference in design and car useage. Acura is not competing with those types of cars with the TL.

 

Take the heads to an engin shop and have them cut the manifold off and tap some holes in the head..Then find some headers that fit. Wouldnt it be great if it were that easy?