I'm going to start my build this weekend. I was looking at 686cc with 11:1 compression. Stg 1 cam. I hear that the stock rod is weak. My question is.... What puts more stress on the rod? I don't want to change mine because I'm kinda broke. I only drag race on sand and hit the trails. Is it an issue with too much compression or the weight of the larger piston? Should I go 673cc with 11:1 or 686cc with a 9.9:1? Stock is 9.2:1 I believe.