RE: do i need the baffle?
You may, or may not get a rpm increase by removing the baffle, depends on the engine and exhaust system. Drilling out the exit pipe also may give you some additional rpm, but at the expence of needed back pressure? If your bird runs lean in the turns, chances are you went to far. Fix it cause your hirting the engine in every turn. Want your engine to scoot just a little more? Learn to use a good tackometer and where your engine is most happy. Funny thing is each and every engine will be a little different. Its up to you to find where each one is happy. Usually you can peak it out and back off 5-600 rpm and be in the safe range. I have one that runs best just into the pipe from blubbering, still rich. Once in the air it cleans up, unwinds like crazy and gos like a striped butt bat. Peak it out and back off 6-800 and its a fishing weight at best. A Webra 55 pulling a 10 X 10. ENJOY