[72LuxuryLeMansLa.]

Originally Posted by promptcritical

Take it out of the car and disconnect “everything” and run it on a test stand so you can get your hands on all of it. That’s a possibility and at least does something to try to diagnose it. Then you’ll know.

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[Gary H]

I know this isn't much help but it sounds like valve train noise to me. Have you tried removing one plug wire at a time while it's running to see is the noise changes on a given cylinder?

[TedRamAirII]

Originally Posted by Gary H

I know this isn't much help but it sounds like valve train noise to me. Have you tried removing one plug wire at a time while it's running to see is the noise changes on a given cylinder?

I agree Gary, its too slow of a knock to be Crank Speed Related. I stated long ago to crank it up cold, and get a hand on the engine and FEEL for the knock, Valve covers, Valley Pan, Etc. It has been stated by people here,in the know, that its near the rear/ Distributor area. The Valley Pan is the only item near the distributor that could transmit any cam speed rhythmic noise. 20 minutes and that valley pan could be off. After the engine being apart, I cant imagine it being anything "catastrophic".

[ponjohn]

Originally Posted by TedRamAirII

I agree Gary, its too slow of a knock to be Crank Speed Related. I stated long ago to crank it up cold, and get a hand on the engine and FEEL for the knock, Valve covers, Valley Pan, Etc. It has been stated by people here,in the know, that its near the rear/ Distributor area. The Valley Pan is the only item near the distributor that could transmit any cam speed rhythmic noise. 20 minutes and that valley pan could be off. After the engine being apart, I cant imagine it being anything "catastrophic".

Do it with a long screwdriver with the handle in your ear.

[TedRamAirII]

I would think, disabling a spark to each cylinder and NO change, would rule out a Wrist Pin. But I think its a Wrist Pin.

[Va68goat]

HWYSTR455,
We tested for a vacuum leak last year and nothing was discovered at the intake.

[Scott Stoneburg]

Ok. Let focus on whats up now. Not 2 years ago, those pics dont help much right now IMO. If you cut the oil filter open right now. Does it have any metal in it? If not...then I'm thinking piston slap, maybe wrist pin.

[Va68goat]

"QUICK-SILVER",
The guy that Jeff and Paul picked to check the motor out is a great guy and really knows his stuff. Paul was concerned that the fuel I had in the tank was bad. We ran it on race fuel today and the knocking noise was still present. Though this is frustrating, I do appreciate Paul and Jeff finding the guy to come here and check the motor out. At this point, the diagnosis of this motor is between Paul, Jeff and the guy they selected to look at this motor. Now that we have moved past fuel being the source of the knock, I'm hoping we can get closer to finding the real problem.

I know the motor is still shaking around a little bit. That will get addressed as well.

https://www.youtube.com/watch?v=mnHpmYka2mg

https://www.youtube.com/watch?v=SEqz1ipiz1Q

[Va68goat]

chiphead,
I never knew that piston slap would be considered acceptable (not that I even knew that term before I had this motor built). I think Paul realizes that the knocking noise is not normal for this build which explains him helping us diagnose the motor for 2 years. As much as I want to be driving this car, I've pretty much accepted the fact that it's likely that the motor will be pulled in the very near future.

[Va68goat]

Mike Davis,
Definitely not hitting the breather. When we ran the motor last weekend, we pulled the breather off and the knocking noise was still present. We checked the breather early last year as well. We checked if the lifters were hitting the valley pan several times and that wasn't it. I'm pretty sure when Paul had the motor apart this last time, he would have looked for that. The rockers are not hitting the valve covers. We checked that that last year and Paul checked the clearance prior to even sending the motor the first time. That is why he suggested the thicker valve cover gaskets.

HWYSTR455,
No way to the breather. That was checked several times. I think all the easy diagnosing has been done. It's been 2 years and no matter what, the same knocking noise has been present. There was no way to hear the knocking noise while it was on the dyno in Arizona with no mufflers. This is becoming like Groundhog Day.