M30 Donor Car Exhaust

The exhaust system part of the conversion mainly consists of manual work.  The original exhaust installed on the M30 can be modified and used for the 335i.  This is a relatively quiet exhaust system and may help in the car's passing of emissions inspections. The best suited parts for this adaptation come from the e28.  The rear muffler of the e23 also fits quite well on the e30 chassis.

Obviously the complete exhaust system from the Alpina B6 3.5 und B6 2.8 would be perfect for the 335i.  But again these parts are hard to find, and should they be located they are likely to be quite expensive.
 

A slightly more unique system is displayed in these pictures.  The catalytic converter from a 3.8L M5 has been adapted to fit with a set of headers.  The system is finished with a Hartge sport muffler.

e30 M3 Exhaust System

The use of a modified e30 M3 exhaust is highly recommended.  The first section, descending from the exhaust manifolds, must be slightly altered to fit. The rest of the system is a direct fit. The performance exhaust should (conservatively) be made of 2 x 50 mm pipes. 
 

	The floorboards under the passenger's seat will need to be modified slightly to allow the exhaust to fit.  After this modification the heat shield will need to be reinstalled.
	Here, the down pipe of the e23 735i donor car is reused.  It was shortened and the flange was slightly rotated to meet up with the pipes of the e30 M3 system.
	Here the exhaust system has been provisionally installed. The down pipe now need only be guided down and connected to the double flange of the e30 M3 system.
	Only three welded seams were used in this system: One at the front flange to account for the twist, and two at the double flange of the e30 M3 system.

Questions, Comments?