It is common for hi-po 930s to run 30mm bars out back. Mine are 28mm and they're not big enough for my mildly modded engine. My concern was ride comfort when I installed the 28s. I don't want to get into annual kidney transplants.
The next thing I am going to try are adjustable shocks. We'll see how that goes.
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