my headers(stock) have a hole on its gasket? I don't think it's my timing or carbs because I tuned them about 1 or 2 months ago. the backfiring only started happening like 1 or 2 weeks ago, and I only noticed the hole earlier this week. thanks.
I had the same problem about a month ago. I went to the shop to get it fixed, thinking that my carbs were not tuned correctly. I ended up paying a hundred bucks for a job that i didn't need. I went to another shop and they found a hole about the size of a quarter on my header. They fixed it by welding in a new piece. It made quite a difference...the backfiring stopped and the exhaust noise was reduced significantly.