I know there has been considerable discussion on the subject of "optimal" exhaust configuration on air cooled 911's, but after days of scouring, I have not found an answer. So many different views on "optimal". I have old GHL headers/muffler (2 in 2 out) that, when new, gave dyno readings of 202 max hp, 186 max torque before adding SW chip (haven't dyno'd since). Also provided decent heat to cabin, removable cats, great sound (to my ears anyway).
After several years repairing various cracks in the muffler and failed muffler straps (generally only at DE's), I'm deciding between replacing the entire system or just the muffler. For a mildly tuned 3.2 with any muffler, I'm not sure a new, arguably better, header set (tuned, long tubes) would offer much improvement in power/torque over the GHL from the dyno sheets I have seen on this forum. But I have not yet found a replacement muffler that could reasonably be plumbed into the GHL header outlets without additional elbows in the flow path (probably reducing performance) AND that has not shown a tendency to crack under track loads (e.g. dynomax).
Question: 1) Anyone out there still running a GHL header/muffler system who has whipped the vibration cracking problem (natural frequency issue maybe?)?
2) Will a new tuned long tube header system with a low resistance muffler really offer noticeable performance over my above dyno numbers?
Many thanks!
