Trying to dial in my 1994 5.7. Starts easy, idles smooth. Just set the timing. Rev response is very good. However, when I rev it up and let it come back down, it dies. Starts right back up no problem. I have rebuilt the carb. Took it apart and let it soak like I should. But maybe I missed something. Oh, it's a mercarb 2bbl. Thunderbolt IV ignition. Thanks for any ideas. 
