[gtofreek]

They call for .0045"-.0055" clearance. I originally set them up at .0045", It's been lightly honed now twice so it is now around .0047"-.0048" I can guarantee it's not piston slap. It would need .006"-.007" before you would really start to hear anything loud. Piston skirts still measured really good this last go round.

[Va68goat]

Scott Stoneburg,
Thats a good suggestion and thats on the list to do.

68 461 Bird,
I've thought about that and that is an option but there is not a chance in hell that I'm going walk away from the money I have sent Paul. I've been speaking with Jeff Koerner, so thats a good sign. I have been reaching out to Paul by text but he hasn't returned one. I even sent one last night explaining that we need to work this out away from the forum and that I don't think he's a bad guy. No response from him..So, when Paul chimes in and diverts the attention to everything other than himself...I won't let that happen. Fuel??? Really? It's possible that Paul made a mistake and than missed it again when he tore the motor down and I'm fine with that...lets work this out and figure the problem out. Blame it on fuel??... come on!

Sun Tuned,
Second opinion is an option but with the money I have spent to build the motor, diagnosing the motor and then recently spent to fix the motor yet the same problem exists, there is not a chance I'm walking away from that. I'm a pretty patient guy.. I'm focused on getting this motor fixed with or without Paul being involved but you would think he would want to be part of the solution.

64speed,
Thank you for the information. If it gets down to that, I will reach out. As I said earlier, at this point I'm not willing to walk away from the money that I have spent. I've been communicating with Jeff Koerner and he is actually trying to find someone that can come to my house and check the motor out. I'm appreciative of that and we'll see how that goes.

Paul...I'm sure you're reading this so if you're willing to fly to Virginia and take a look..my offer still stands that you can stay at my house. I won't pay for the ticket but you're welcome to stay here.

[HWYSTR455]

It's not difficult to run a line from a gas can to the fuel pump, and it would eliminate any question of the quality of fuel. You HAVE to eliminate ANY possible cause, it's trial and error, so you have to do ALL the steps to have countable results.

Think about it, you put the new tank in when this escapade first began, almost 2 years ago. THAT gas is still in there, and it has sat for that almost 2 years. Adding gas to bad gas makes all the gas in the tank bad. Did you drain the existing gas out of the tank before you added 'new' gas?

Do I think it's the gas? Not really, but I admit it is a possible cause that hasn't been addressed yet.

If any one of the potential causes that were corrected did not fix the issue doesn't mean that there wasn't any issue with the corrections, like the initial timing and/or the rockers. And don't dismiss that the knock could be caused by a combo if issues. It all needs to be right.

The plugs looked a little hot to me, and maybe a little rich. Maybe post a pic or two of those.

.

[Region Warrior]

My last post wasn't intended to mean bad fuel.
Was thinking to much fuel in 2 or more cylinders at idle.
Have you checked carb for debris?
Happened here years ago with a brand new 850 Demon carb.
Rear float suck open upon start up.
Was surprised how much metal debris was in both bowls and rear channels from factory!

[68 461 Bird]

Originally Posted by Va68goat

68 461 Bird,
I've thought about that and that is an option but there is not a chance in hell that I'm going walk away from the money I have sent Paul. I've been speaking with Jeff Koerner, so thats a good sign. I have been reaching out to Paul by text but he hasn't returned one. I even sent one last night explaining that we need to work this out away from the forum and that I don't think he's a bad guy. No response from him..So, when Paul chimes in and diverts the attention to everything other than himself...I won't let that happen. Fuel??? Really? It's possible that Paul made a mistake and than missed it again when he tore the motor down and I'm fine with that...lets work this out and figure the problem out. Blame it on fuel??... come on!

.

Another guy from AZ? You live in VA right? I don't get why after 2 years you are still hoping Paul is going to do something. I get you spent a lot of money with him, but at this point, you need to cut your losses and have another look inside to see where the knocking noise is coming from. Butler Performance is a days drive away, Paul Spotts is in PA and Nightmare Perforance is in CT. I just names a few Pontiac Engine builders I would use and 64speed has a guy he trusts too. I would be dying to drive that GTO by now and burning up the streets in VA .

On a positive note, there's a lot of great advice on this thread. I am hoping for the best for you!

[P@blo]

Originally Posted by 68 461 Bird

Another guy from AZ? You live in VA right? I don't get why after 2 years you are still hoping Paul is going to do something. I get you spent a lot of money with him, but at this point, you need to cut your losses and have another look inside to see where the knocking noise is coming from. Butler Performance is a days drive away, Paul Spotts is in PA and Nightmare Perforance is in CT. I just names a few Pontiac Engine builders I would use and 64speed has a guy he trusts too. I would be dying to drive that GTO by now and burning up the streets in VA .

On a positive note, there's a lot of great advice on this thread. I am hoping for the best for you!

I never can understand why people chime in with comments like this where they expect a person to process and decide like they themselves would. The OP wants resolution and either we are helping him along this path or we are are not.

Making things right is better for both parties involved actually.

[68 461 Bird]

Originally Posted by P@blo

I never can understand

Making things right is better for both parties involved actually.

Sorry you have a hard time understanding. I was only giving advice to the OP and he is the only party I cared about. It appears others agree if these other diagnostics don't work out, its time to dig into it.

[OCMDGTO]

Without a doubt the most depressing thread on here. I keep hoping you are going to say you solved this mystery and are out shredding tires. The down time I had on my engine swap which was only a few wks about killed me. Gotta have that Pontiac fix

[64speed]

Originally Posted by 68 461 Bird

Another guy from AZ? You live in VA right? I don't get why after 2 years you are still hoping Paul is going to do something. I get you spent a lot of money with him, but at this point, you need to cut your losses and have another look inside to see where the knocking noise is coming from. Butler Performance is a days drive away, Paul Spotts is in PA and Nightmare Perforance is in CT. I just names a few Pontiac Engine builders I would use and 64speed has a guy he trusts too. I would be dying to drive that GTO by now and burning up the streets in VA .

On a positive note, there's a lot of great advice on this thread. I am hoping for the best for you!

I agree. You have been beating your head against a wall for how long now? My engine builder fields two cars for the Southeast Gassers Association and most times they are winners. He has built two 421s for my friend that were absolute screamers and he built Caster1 461 that is amazing. Its torn up a transmission already and is working on tearing up a rearend. Wayne will NOT let you leave without a warranty and you attesting to the fact that it is good to go. With Wayne you will have to deal with him in person which is a drive but if you get it from him you will get to see and hear it run on his stand and when you get it back home and you install it in your car if it knocks then well then you got a problem somewhere else. Wayne is reasonable too. He did all my assembly work and machining for 1600 bucks and thats including ordering custom pushrods and providing all gaskets except head gaskets and all the little trinket bolts etc that everyone forgets.

[P@blo]

Originally Posted by 64speed

I agree. You have been beating your head against a wall for how long now? My engine builder fields two cars for the Southeast Gassers Association and most times they are winners. He has built two 421s for my friend that were absolute screamers and he built Caster1 461 that is amazing. Its torn up a transmission already and is working on tearing up a rearend. Wayne will NOT let you leave without a warranty and you attesting to the fact that it is good to go. With Wayne you will have to deal with him in person which is a drive but if you get it from him you will get to see and hear it run on his stand and when you get it back home and you install it in your car if it knocks then well then you got a problem somewhere else. Wayne is reasonable too. He did all my assembly work and machining for 1600 bucks and thats including ordering custom pushrods and providing all gaskets except head gaskets and all the little trinket bolts etc that everyone forgets.

Warranty on performance engines is interesting...

[64speed]

Originally Posted by P@blo

Warranty on performance engines is interesting...

Yes if you let him build it with his approved parts or agrees with the quality of the parts you provide which was SCAT in my case then if he puts it on the dyno and it blows up he will replace it. If you installed it in your car and it knocked right after he ran it in, he would fix it. If you blow it up racing, well you are on your own