I assumed you've already checked out all your vacuum lines, timing, etc.?? As others' suggested, if you haven't checked to see if the distributor canister can still pull some advance (i.e., diaphragm doesn't leak) and your base timing is spot on as well as the mechanical advance weights are good, then go with it.
If your timing is retarded and/or vacuum/mech advance isn't working, I think you'd notice that at highway speeds. Good to check anyway to rule it out. The other part of this equation is...….does it still have the original timing chain in it? Just wondering. Those plastic teeth on the cam gear may not have given way yet, but they will. And your cam would be retarded as hell.
Pure speculation.
I've replaced almost every vaccum line on the engine. Except the one in the other thread I posted and found out it is connected to the EGR valve above the water
pump But that's a whole other can of worms.
I didn't know about the plastic teeth. As far as I can tell, the engine has never been opened. When I installed the new water pump, usually you can see
evidence of something other than factory work.
Thanks for the speculation and calling it what it is..........I think I'll stay within the area of possible hose collapse, or radiator blockage, as my first two areas to address.
As far as the timing, I will throw a light on it....but it seems to run so well with no engine ping, knock, instant start, smooth idle, I actually stood there and remarked how well the carb rebuild has made this engine come to life. I owned a 1978 Pontiac Grand Am with the enemic 301 (sorry Pontiac fans) and this 350 really stood up where the 301 laid down. This is just opinionated observance.....unlike what Joe Friday wanted............JUST THE FACTS MAM...........JUST THE FACTS.