I installed a 290 hp crate 350 in my 1993 silverado which had a 305. I kept the stock intake and throttle body. The motor runs good but it wasn't idling good. I adjusted the set screw on the throttle body and got it to idle good in park. However when the truck is in drive it idles down and wants to stall.Checked for vacuum leaks and don't seem to have any. Is this because I'm using the throttle injection. Should I switch to carburation. I would prefere not to as I enjoy my remote start in the cold mornings. Looking for some suggestions.  

I've read articles on this,one issue is getting 350 throttlebody injectors to replace the smaller 305's injectors.The cam you have is bigger than stock,you'll need to factor in this also. That's as far as I can go on this,hope this helps.    WIEDER