NavyE6FE -I originally thought the stock muffler would work, thus the notch in the firewall, but then learned the barrel made contact with the cowling, which I didn't like after I cut the cowling as well. I then ordered a Slimline Pitts muffler from DA for about 136.00. I also ordered a new cowling, arrgh! No problems with the socket head screws coming lose and the muffler fits nicely in the cowling without cutting. You will notice a fuel valve in one of the photos. I have since replaced this with a fuel dot after the fuel valve developed an air leak. Many had warned me about this, but I had never had any problems with them until I tried one on a Gas engine. I suspect that vibration wears out the seal causing the leak. I had a DS as a result of this which is when I learned how challenging a DS can be on this bird at 17+ lbs.

Both Pitt-I and Pitts-II are the updated models, but I still reinforced the firewall in using a gas engine. I have found that regardless of which gas engine you use, vibration really causes things to loosen up. The screws holding the Cabbane and interplane struts need to be checked frequently to be safe.

rcjake-RCU - Arizona??? Man, that would be a haul from N. Al. I will pass on this one, but sure would like to see some photos of a Pitts Fly-in. bet it will be a fun event.