Originally posted by warmonger:
I agree, piston slap doesn't sound that way.
As far as the high octane fuel, how is that going to help get rid of valves kissing the piston domes? Do you think it's pinging we hear? I'm pretty darn sure its metal to metal contact.
Maybe if you have a different interpretation you can explain it?
I'm just curious, not trying to be a Diick by any means.
warmonger
HEY, Listen here Dick!!! :p LOL. The idea was if it was "piston slap" is that it has some type of physical contact with either the valves or loose rings. For the pistons to hit the valves, the cams would be off by more than one tooth (hopefully not the case). With the valves off by one tooth in either direction, the engine will run, but with this condition happening... If the cam is advanced, the valves open and close a little to early. In this case, the intake cam would be the most likely culprit, allowing the fuel mixture to enter the combustion chamber to soon, before the piston is on the down stroke, causing something very similar to a detonation knock or ping. That is what I'm hearing here, though it is hard to know for sure. If the cams are retarded, the engine still runs also, but does not have the ping sound. Rather, it makes a bit more of a farty thud sound (kinda like a valve float noise) and doesn't have any power until much higher in the rev range when it gets back "on" the cam.
Forgot to add, the racing or AV gas would help in the situation of advanced cams since it would slow the burn and not ignite on contact with the hot piston. It still might ping or knock a little bit, but would for sure quiet it down. Hopefully, it's the cams being a little off and ping happening vs. something physically hitting something else... ouch.
