I recently put a GFB deceptor on my 34 it said to use the thin black gasket, the plumb back hose is a bit of a stretch but it just fits on. Since mine has been on I have had no problems with stalling and im running at 3/4 atmo. Every now and then im getting the odd backfire between gear changes below 3,000RPM I think it might be the spring rate i'll have to have a play with it.