Pinging

blown motor · September 27, 2025, 02:39:38 PM

I have a 440 with Edelbrock top end kit. I don't know the compression but I'm going to reach out to Edelbrock and see what they say. I use 91 octane fuel. I hear a bit of pinging when the engine is cold but once it's warmed up good I don't hear it. Timing advance is 16*. What's not right that's causing the pinging?

Cuda Cody · September 27, 2025, 05:16:17 PM

Are you sure it's pinging and not forged internals expanding?

If it is pinging, have you tried some octane boost or lead to see if it changes the cold pinging?

blown motor · September 27, 2025, 06:59:32 PM

Quote from: Cuda Cody on September 27, 2025, 05:16:17 PMAre you sure it's pinging and not forged internals expanding?

If it is pinging, have you tried some octane boost or lead to see if it changes the cold pinging?

I'm using 91 octane, could try some 93 I suppose. Hadn't thought of the expansion thing. Is the "expanding" more audible with aluminum components? With aluminm heads and intake what's forged? Just the crank? I'm so uneducated, lol.

Chryco Psycho · September 27, 2025, 08:57:13 PM

If it is pinging it is carbon build up , too much timing or poor fuel , more likely to ping hot than cold , could be expansion

pschlosser · September 27, 2025, 10:05:28 PM

You need only try the octane boost one time, just to test and confirm it is pinging. If, after boosting the octane quite a bit, if you still hear pinging, then maybe it's not pinging. If it IS pinging, retard the timing back a few degrees and confirm it goes away. Again, just temporarily to confirm.

MoparLeo · September 27, 2025, 11:31:36 PM

Engine "pinging" or detonation usually occurs when the engine is under load.
We need to confirm what you are actually hearing and under what conditions.
Can't make an educated recommendation until then. Just guesses based on the limited info you have shared.

https://www.youtube.com/watch?v=WuCUGcqO5SE&t=37s

Cuda Cody · September 28, 2025, 08:09:05 AM

If you have forged pistons they can sometimes takes time to heat up. You might be hearing some piston slap until they warm up and expand. The reason I bring that up is just like others have said, it's more likely to be a pinging issue when hot and or under load. When it's cold you may be hearing forged parts which will stop when they get warm. "IF" going up in octane does not solve the issue, then it might just be engine tolerances and forged parts needing to warm up.

Quote from: blown motor on September 27, 2025, 06:59:32 PM
Quote from: Cuda Cody on September 27, 2025, 05:16:17 PMAre you sure it's pinging and not forged internals expanding?

If it is pinging, have you tried some octane boost or lead to see if it changes the cold pinging?

I'm using 91 octane, could try some 93 I suppose. Hadn't thought of the expansion thing. Is the "expanding" more audible with aluminum components? With aluminm heads and intake what's forged? Just the crank? I'm so uneducated, lol.

blown motor · September 28, 2025, 09:55:09 AM

I don't know what internals of the engine are. Just the add ons. Thanks for all the input.

DeathProofCuda · September 29, 2025, 01:24:16 PM

Are you actually hearing the pinging while the car is idling, or only while driving when the engine is cold and under a load?

The reason I ask is because you said your timing advance is 16 degrees, which is kind of useless information unless the pinging is actually occurring at idle. While driving your advance will be higher, due to the effects of mechanical and vacuum advance, and we have no idea of what that might be without knowing a lot more about your setup and under what conditions the pinging is occurring.