well hello folks, it's been a while since i've had to tune my other holley. So i just put a new motor in my 67 cougar with holley 600 double pumper. I think i kinda know where to start but opinions and suggestions always help. Ok, this is what it's doing. At idle you can wrap up the carb to full throttle with no hesitation sputter or and problems at all. Now when you drive it from a dead stop you can take off and it's all smooth, until you get to where the secondaries come in. Then it breaks up bad and will clear up after a second. I'm thinking secondary adjustment/nozzle size... sound right? this is my set-up: roller 302 edelbrock aluminum heads trick flow stage 1 cam long tubes edelbrock intake stock dizzy with petronix Carb: used but i just rebuilt it. 67 front jets with 6.5 power valve 73 rear jets no power valve 28 front nozzle 32 rear nozzle fuel level: just barley trickles out when you push down on fenders i think tomorrow i'm gonna start with playing in the secondaries. ***also i just took off a edelbrock 600 that was fine, so it's nothing to do with ignition**** thanks..