Ok so I decided to get a rebuild kit an rebuild the carb. The timing is spot on top dead center an advanced 4 degress. I then was adjusting the carb an it started to back fire an well catch on fire. so I stoped tuning the carb. Im buying a rebuild an I got a guy that im going to pay that will come to my house an tune it for me. an teach me a thing or two about tuning the carb he's also gonna double check my timming. I also noticed that before hand i checked the spark plugs an they were all gapped to .45 so I regapped them to .35. I also noticed that all the spark plugs were black so I cleaned them up. an what not. ever since I have been getting carb fires. So do any of you know what would cause the carb fires possiably?also I was on holly an they have a chart that says that I should have at least a 850 DP carb but I have a 750 DP could that do somthing. any who thank you.