350sbc Wont Run!

[fostrem]

First off I would like to say I am a new member but have been browsing for years, love this site! I recently bought a 76 k10 short bed with a 350sbc and a th350 tranny. When buying the truck it ran well and I got good compression out of each cylinder. One the drive home I was getting great power on the highway long with in the following week. It had a bit of a hard start so I took it down to a local shop to have the timing checked along with the whole engine.

Their first diagnosis was that the truck was running great although the initial timing was set at 38deg advance! This seemed incredibly high so I had them replace the following: timing chain/cover, harmonic balancer, a couple valves and covers, and distributor. After all this the damn thing wont start! It will start with about half throttle but the carb is spraying some gas and once in a while it will blow some air out the carb. If you let off the throttle, it will drop low and sputter for a while then die. Also while at WOT, it hits 3000 rpm and yes the secondarys are opening in my carb. Im stumped and the shop gave it back (i dont want them doing any more work). They say it is set at 10deg advance before vacuum. I havent had time to check due to work and thought I would ask yall. Could it be a vacuum leak? Worn cam? Carb problems?

Thanks in advance!