[Johnny Danger]

This is a quote from a previous thread that I contributed to.


I've experimented with several different exhaust configurations before choosing the final system for my 3.2 S. I found the following set-up produced the best results in terms of performance and reliability (keeping my vehicle OBD II compliant).
Here's my ditty:

1. A less restrictive, high quality after -market cat back exhaust.
2. By-passing/deleting the secondary cats (they're like having an extra set of thumbs).
3. Headers and cats that stick with the basic principles of the oem design, however, they incorporate longer, equal length primaries that flow into a merge collector, along with lower cell - high flow cats (something on the order of HJS 200 cell).

The final result yielded the following: No need to relocate O2 sensors, make bungs, chase CEL's, reprogram the ECU, or worry about emissions ! Excellent results in terms of improved power and performance. And perhaps equally important - great sound ! All this begs the question; who makes headers and cats that follow this design principle ? In all of my research and experimentation I discovered 2 companies that manufacture such a system. M&M exhaust in Germany ($$$$$$$$$$$$) who's products are imported exclusively by FVD/Brombacher and FabSpeed.

To further elaborate on the topic, on the assumption that I decided to forgo the oem headers/pre-cats set-up, in addition to sourcing excellent, high quality headers (which was never a problem), in turn I needed to find find some high quality, less restrictive secondary cats (forget the oem ones - you may as well stick a banana in your tail pipe - it would be less restrictive). Therein lied the problem. Not only were there very few aftermarket manufacturers that offered these items, the ones that did were never the correct application. Generally, the cell count was too low. In which case, a good deal of back pressure was lost. This in turn resulted in a significant loss of low end to mid range torque. As most are aware, for those who primarily "street" their vehicle, low and mid end torque is essential.