1996 1500 2wd sbsc w/305 vortec. I got it home today, bought it from a guy that stated the intake gasket was screwed and pouring out coolant and since the temp gauge stopped working he thinks he overheated it acouple times.

Now it wont start right up, Checked the backpressure before the cat and it checked out bad. So i lopped it off and it didnt help, Im getting fuel to the rail and i can hear the fuel pump. When you play with the throttle enough it will start and run, After about 5min it will seem to run somewhat smooth but only rev to 3k and idle is very questionable.

Is this something simple or is this damn thing done with? Im a heat ignition kinda guy, Never messed with gas engines.

 

You may have fuel, but do you have enough fuel pressure? Check the fuel pressure first as low fuel pressure will keep an engine from running correctly.

 

If it will start, and run, not really the fuel pump. Could be weak, hence having to prime it. A 305 is a small block. You suspect it could have been overheated. I'd suggest you decide what you want from it, more power I'd suggest something other than a 305. You might swap it out with a diesel.