performance improvements

[rick0312]

My '69 C10 LWB has a '76 305 V8 motor that was rebuilt and installed back in 1988. Runs well, but I have noticed a few problems....
1. When starting after sitting for a few days i get alot of white smoke. the smoke subsides once the engine is warmed up.
2. Classic rear seal leak, not that bad though. A couple of drops on the ground per week. Oil level is stable.
3. valve chatter at part throttle sluggish throttle response in 2nd and 3rd gear.
The p.o mated a saginaw manual 3peed to this engine with aftermarket shifter on the floor. Could this be the problem?
This truck is basically a weekender and I have no intention on a full restore. I have refurbished this truck in order to keep it operational. i have installed new front and rear suspension. New floor pans rocker panels etc.

I quess my question is what can I do to this motor to rectify the sluggish performance I am gettting currently? I have advanced the timing and replace the vac can, although there was some improvement I still get the sluggish response. I am thinking of upgrading the cam????

thanks for all your input!!

Rick