First and foremost Thank you to everyone on Ratsun.You guys have helped me out alot.Well i aquired a l20b out of a 510 to put in my 620.Dual side draft 40 dcoe carbs,cannon intake,peanut head,flat top pistons,not sure what else is in it.did a pressure test cylinder 1,210 2,3 and 4 where between 125 and 135.I was unable to use the 40 dcoes because they hit the brake booster.:mad: So i threw my down draft on there got it to start and the vent tube on the valve cover was spitting oil out like it was going out of style.The crankcase tube on the intake side of the motor has been cut and welded shut.Is that correct???OHH yeah i did a leak down test too and it held the pressure over night.also adjusted valves .008 and .010(Thanks hainz)Any help or suggestions would be greatly appreciated.Thanks guys