[Va68goat]

NeighborsComplaint,
I have a felling that the motor is going to come out. At this point, I just don't know by whom.

chiphead,
A few guys have worked on the motor. None of them did anything that wasn't instructed by Paul or approved by Paul. The guys that have worked on the motor are all experienced car guys (25+ years of experience). I don't know how far their guy is going with the motor. He's doing some more diagnosing that Paul has suggested.

ponjohn,
Thats a consideration. The machine shop that inspected the heads has a dyno and I believe they have a test stand. That may be an option for the guy that Paul and Jeff have looking at my motor.

[HWYSTR455]

I honestly can't see what removing the engine mounts and setting the engine on wood would help?


.

[68 461 Bird]

Originally Posted by HWYSTR455

I honestly can't see what removing the engine mounts and setting the engine on wood would help?


.

either do I, except cause more damage.

[Va68goat]

ponchjoe,
I've heard of CVM. They're about 2 1/2 hours away. At this point I'm not getting in the way of Paul and the guy they found to look at this motor. I want to avoid sending this motor back to Arizona if at all possible.

chiphead,
I agree. Since we now have a third party looking over this motor, I think it would be a good idea to continue to let him see this through, if he is willing. I really don't want to see this motor leave Virginia. As for the pistons, I don't know what it means to coat a piston but thats not what I paid for. I've spent a ton of money on parts that were suggested that I obviously didn't need and the knocking noise has never left.

STEELCITYFIREBIRD,
We'll get the idle down where it needs to be. I believe Paul said 900 rpm would be good for idle. Though I want to get to a point where I can enjoy this motor, I'm patient enough to let this play out.

[chiphead]

Originally Posted by Va68goat

chiphead,
I agree. Since we now have a third party looking over this motor, I think it would be a good idea to continue to let him see this through, if he is willing. I really don't want to see this motor leave Virginia. As for the pistons, I don't know what it means to coat a piston but thats not what I paid for. I've spent a ton of money on parts that were suggested that I obviously didn't need and the knocking noise has never left.

.

I get that, you don't want to throw more money down a hole. The challenge here is that if the engine gets diassembled, it's likely going to need major component replacement to rectify the noise. If it's a machining or assembly error, then the builder should rectify that for you.

The challenge with something like piston slap is that it can be acceptable from a technical standpoint. A 2618 forged piston with .005" skirt clearance is a common clearance, and it may slap depending on piston geometry. A 4032 piston with .005" has a good chance of slapping, even when warmed up. That's why I asked what the piston was made out of. We know you're at about .005" skirt to wall now.

My 400 motor slapped at .0055" and I ran the snot out of it for years on the street, incl making several nitrous passes at the track. My machinist warned me it might slap, and it did. The early LS motors slapped before they went to coated pistons and they ran 100K like that. Point being is if you have piston slap with no other issues, some of that is normal with a heavily modified engine.

Excessive piston slap is when the piston has enough clearance to rock A LOT in the bore as it goes over TDC and BDC. That's what causes the slap noise, as the skirt to wall clearance transitions from one side of the piston to the other as the piston changes direction in the cylinder. This will cause accelerated piston ring wear and upset ring sealing. In severe cases, piston rock can damage the skirt and require replacing the pistons. So checking the skirt clearances should definitely be done if the engine comes apart.

[redhawk44]

I have heard you guys talking about piston slap and thought it was the piston coming too far up. After reading Chip I learned something new.

The challenge with something like piston slap is that it can be acceptable from a technical standpoint. A 2618 forged piston with .005" skirt clearance is a common clearance, and it may slap depending on piston geometry. A 4032 piston with .005" has a good chance of slapping, even when warmed up. That's why I asked what the piston was made out of. We know you're at about .005" skirt to wall now.


Thanks Chip.

[ponjohn]

Originally Posted by HWYSTR455

I honestly can't see what removing the engine mounts and setting the engine on wood would help?


.

What's the difference between that and an engine run stand?

[68 461 Bird]

Originally Posted by Va68goat

A few guys have worked on the motor. None of them did anything that wasn't instructed by Paul or approved by Paul. The guys that have worked on the motor are all experienced car guys (25+ years of experience). I don't know how far their guy is going with the motor. He's doing some more diagnosing that Paul has suggested.

.

So what is their guy doing that you and your guys haven't done in the past 2 years and 165 hours of diagnostics?

["QUICK-SILVER"]

Originally Posted by 68 461 Bird

So what is their guy doing that you and your guys haven't done in the past 2 years and 165 hours of diagnostics?

Judging from the latest videos that went up...Appears they have the hired engine tech "grasping at straws".


Grasping at Straws meaning:
To be grasping at straws means to be willing to do, say, or believe anything that offers even the slightest hope in a desperate situation, even though there is almost no chance


Running race fuel through it ain't helping

Clay

[MarkS57]

Originally Posted by "QUICK-SILVER"

Judging from the latest videos that went up...Appears they have the hired engine tech "grasping at straws".

Having my rose colored glasses on , Its possible that the result of the selected engine tech not finding anything external to the engine to explain the knock will result in the tech pulling the engine followed by a free ride of the engine back to the Koerner Racing to be made right...

One can only hope

[STEELCITYFIREBIRD]

If the noise is more pronounced or audible at lower RPM, and as as you stated...
Get the idle down lower, adjust the idle mixture/speed in now that the vacuum leak is? repaired. Clean or replace spark plugs if needed to smooth out idle.

I agree Joe, experienced sets of ears hone in on problem area pretty quickly.