I had it at 33° before the swap but the howling coming out of the trans was so loud I never heard any spark knock. It is really light. I'll experiment with it after I get the little things taken care of. I'm waiting on a couple 10" 1000 cfm fans I'm going to put on the condenser and a trailer brake controller. I think I got the fuel gauge working decently now. I may even put a slightly colder plug in it.