Well one of my engine is making a ticking sound. 350 SBC Definetley sounds like a rod. The sound it not constant. The ticking is only there above 2000rpm with little load on the engine. At idle and under load the ticking stops. Oil pressure is the same and the engine is not running warmer.

I am thinking that one of the rod bolts loosend or stretched. Sound right?

Thanks for any helps,
Steve

Could just be a bad lifter. A rod would make more of a a knock rather than a tic. or possibly a wrist pin?

Rods dont tick,when the rod bearings go bad they knock and sound comes from lower end of motor.

Ticking sounds are more like a valve/lifter out of adj or possibly a header or exhaust manifold leak. It could also be a bad or loose heat riser if your running stock exhaust manifolds.

If your not sure where the noise is comming from then take the car to a good machinest in the area and let him listen to it so he can give you some idea of whats going on.

scott

As mentioned...quite possibly an exhaust leak...

My fault, I really should have said a knocking sound. It's not valvetrain. I have a XE274 cam with Rhoads lifters, it sounds like a solid lifter engine, ton's of valve train noise.

The "knocking" is very load dependent. At idle it is fine. Rev the engine up in neutral, it makes the loud knocking noise. While driving along at over 2000rpm it knocks, press the gas pedal to load engine and it goes away. Take foot off gas it comes back.

The noise started very shortly after going around a corner and hitting a patch of gravel. When I saw the tach it was at 7K. So it went over that. Stock 4-bolt short block. Needless to say the motor is coming out for sure.

Thanks,
Steve

I would check all piston skirt/cylinder wall clearances when you get it out. I think you will find that one or more is out of spec and that noise you hear is piston slap. What type pistons are you running, forged or cast?

Cast pistons. The short block is bone stock, never touched, the way it came from the factory. It came from a 77 K5 Blazer that read 44K on the odometer. That could have been 44K, 144K, 244K.... I have no idea. I have heard piston slap, and it usually happens at start up with no load. Not piston slap.

I have lost a rod bearing in a 305. This sounds the same, just quieter.

Thanks for the help,
Steve

Are you running an automatic trans?? A broken or cracked flex plate can be deceiving and sound like a knock

If you turned it over 7000 then it probably stretched a rod and spun a bearing.

It's a manual.

I am really thinking stretched rod bolt. Don't think rod spun, it is possible to stretch a bolt and not have a bearing spin? I have lost a rod before, and that made noise all the time, not just sometimes.

Thanks again,
Steve