Keep the rev's down on that motor or you will blow it up. nothing over 10,000 static on the ground peaked. 12-8, 13-6 works well with that engine but you will need to do some experimentation to find best combo. The 65 has a low red line and a long stroke and a small carb so high rpm's do nothing, pulls real good in the low to mid 9's. Keep it a bit rich too or you will be an unhappy guy as well.