As the ad states, they do not yet have a 930 unit in production.
I have not looked any further into it than just finding that they do in fact exist. I plan to do something like that in the near future but will try a fully adjustable unit first.
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8