6 Cyl Swap - Supersprint fitment
 

I recently completed swapping an M54B30 into my ti, and really wanted a Supersprint rear section. I have one on my E30 325i and it just sounds perfect with no drone... I was emboldened by Jim's swap guide to go for it, and wanted to post back here that it is a (relatively) simple fitment.

Exhaust Details:
- 6 cyl engine swap
- BMW Stock E36 6 cyl tubular exhaust manifold
- BMW stock E36 M3 center section

The above setup will fit as stock in the 318ti, using the rear cross bar hanger from the M3 for the center section.

- Supersprint part #787826 (previously called #787806) which is for the Z3 3.0. This part has dual in/dual out to match up with the M3 center section

Fitting
- I used the Supersprint-supplied hardware to hang the rear section where I wanted it before I went to the exhaust shop to get it fitted. This made the conversation with the exhaust guy easier, and whole process quicker.
- When I test fit the exhaust, I used it as a template to figure out where to cut on the rear apron to fit the dual exhaust. It was pretty straight forward to cut the apron itself and then use a file and sandpaper to make it look fairly stock.
- I brought the car to an exhaust shop to get the Supersprint connected to the center section. Pretty much any exhaust shop can do it - two "S" pipes need to be created to bend the flow from the M3 center section outboard under the rear subframe to the Supersprint. There is ample room for them to work.

My requirement was that they create this connector in a way that it can be disconnected and removed. In the end, we didn't modify the Supersprint at all, but we did remove the stock connectors on the M3 center section pipes and used a slip connection instead. It was about 2 hours of work for the exhaust guy.

As a note - you can go to a high-end exhaust shop that has mandrel-bend equipment to get a smoother, less restrictive flow for this connector piece. I was limited in my shop choices, and they used pinch-bends to create the connector. But I'm happy with the result.

The sound is pure Supersprint - sublime, but roars when you get into it. Absolutely no "drone" at any speed. Love it!

Hope this makes sense - I wanted to post this as an option for future swappers, and to confirm Jim's hypothesis on the Supersprint rear section fitting. It works!

Drew

Awesome! Thank you for your detailed report!

I'm planning this along with headers and hi-flow cats etc. coming up soon with the expiration of my emission testing requirements. MAYBE cat delete, but I'm not a fan of the fuel smell without cats... makes it seems like a car that needs repair, since so few actually smell like that any more.

The only detail I'd like to have seen is how the Supersprint aligns with the 323ti real valence. I have one for my car, with the heat shield installed as well, but haven't done the exhaust due to the emissions regs. I don't want to do it twice!

Hey Jim - Just FYI the cutout I made for the Supersprint is left-aligned with the single cutout of the original 318ti rear valance. I left the single cutout intact and just extended it right to double the size. I would think the 323ti rear valance would end up being in the same place? Hope it works out for you!

You did what I have currently, but cut for the M3 rear section.

I'll either do exactly what you did, and fit the muffler to the valence, or cut the tips off the M3 muffler and add them to something custom (which will be aligned with the valence).

I cut my opening with square corners and added some rubber edge trim to the opening, but basically the same.