This might be interresting to someone planning on buying an aftermarket exhaust system for the 318ti. I noticed that some of the systems are available in the US.

The June issue of Sport Auto (German magazine) had a comparison of aftermarket cat back exhaust systems fot the E36 318 ti. They dynoed all the exhausts without any changes to the stock chip. They used the same car in all their measurements and the readings were 145.1 hp and 175.7 Nm as stock (factory claims 140 hp and 175 Nm). The results for the exhausts were the following:

Make           Price  Material  Quality   Sound   Power  Torque
                DEM    SS/AS     +/0/-    +/0/-     hp      Nm

Breyton        1201     AS/SS      +        0       +1.0   +2.2
Eisenmann      1023     SS         -        +       +1.5   +0.4
G-Power        1190     SS         -        +       +0.6   +2.0
Hiob            774     AS/SS      +        0       +0.4   +2.8
H+H            1092     SS         -        +       -0.2   +3.3
Lorenz          760     AS/SS      +        -       -0.8   +2.5
MK              784     AS/SS      +        0       +0.7   +1.1
Supersprint 1   700     AS/SS      +        0       +2.0   +3.1
Supersprint 2   782     AS/SS      -        +       +0.3   +0.4
Schirmer       1190     AS/SS      +        -       -1.0   +1.6

Material: SS = stainless steel

AS = aluminized steel

Supersprint 1-rohr was ranked best in the power gain area. It was the only one to improve torque over the whole rpm range. The others tended to improve torque in a narrow (peaky) rpm range. Schirmer was ranked best in build quality. H+H got the highest ranking in the sound category.

Note! G-Power, H+H, Hiob and Supersprint 2 will not fit under the factory bumper since these have 2-pipe tips. The Breyton has only 1 tip but it so big that it has the same problem.

Jari