Originally Posted by Fidanza

This how i tune my engine, and most grp factory guys. You lean out the LSN till it starts pinging. then richen the bottom four hours. The bottom should be set. Then the HSN should be almost flush. You want it just to clear out on the top. Its not a big revving motor. Then when you come in after warm up, it should be around 170. and if it is then its good to go.

Hope this hepls