I am buying an 83 k-10 with the stock 305. My concern is a sound that occours under load ex) after up-shifting, hill climbing etc. It goes away if you give it more gas or take your foot off the petal. Someone told me it's a knock, but knocks have been described as a pinging, I guess thats kinda vauge but I woulden't call it a ping. Also it has what I think is a lifter tick, it's there at startup and goes away with a little throttle, comes back with a little more but not constant through the rpm range and does not go away after driving. I was just wondering is anyone has had a similar experience, think these issues are related, or knows a remidy... Oh, and she only has 58,000 (no the odo didn't rollover) so needless to say she's been a sitter.

 

Is the sound a click click click click click that clicks faster as the rpms go up?

 

It goes away and returns throughout the rpm range. I also ran a tank of super and it took away the noise under load, but it returned as soon as i put regular in!

 

There are a couple thing I am thinking of that could be the problem.
1)Octane is not an actual substance, it simply means "a fuels ability to resist detonation". When the atomized fuel in the cylindar is compressed, it is more susceptible to combust. So when the octane rating on a fuel is lower and the combustion ratio ishigher in the engine you will get detonation. Detonation is a more sophisticated way of saying engine knock. You should either use high test gas or you couldgetoctane booster and poor it into you tank every fill up.
2)When the motor oil is not circulatingwell to the head, the valves make a clicking noise because of friction due to lack of lubrication. A good way you can check is totake your car out for a ride, do whatever kind of load test you do, and come back and pop the hood. Take off the oil cap going into the valve cover, there might be smoke so either wait or try and blow it out. Peek in there with a flash light and see if the rocker arms, pushrods, and valves look dry or not.

Tell me what happens, I'm pretty sure its one or the other. Good luck with it...