Maximuim Pin to lock Clearance

[Kenny M]

I am repairing a Mess of a 428 CJ engine. The engine was already built but never ran. I have never seen something this bad before.,but I won't go there. I believe he is a member here. Anyway The last problem that I found is the Piston to Pin Lock Clearance is .042 Autotech Pistons with wire lock and
.975-2700 130 Gram Pin. If I didn't already balance and torque plate the engine and have the crank in it., I would just replace the pistons and pins.
Does anyone know of a pin vender that may have the same pin in a 2.725? I understand the simple thing would be to call Racetec, but I do not do business with them anymore. I did call CP and I am waiting a call back. But I wanted to get you guys thoughts.

Thanks
Ken Maisano

[cgarb]

Any way to make or source a shim of some kind? What about not using clips and use buttons, either aluminum or nylon type. I saw that on a set of boss 302 pistons one time from Arias.

[Charliesauto]

I am repairing a Mess of a 428 CJ engine. The engine was already built but never ran. I have never seen something this bad before.,but I won't go there. I believe he is a member here. Anyway The last problem that I found is the Piston to Pin Lock Clearance is .042 Autotech Pistons with wire lock and
.975-2700 130 Gram Pin. If I didn't already balance and torque plate the engine and have the crank in it., I would just replace the pistons and pins.
Does anyone know of a pin vender that may have the same pin in a 2.725? I understand the simple thing would be to call Racetec, but I do not do business with them anymore. I did call CP and I am waiting a call back. But I wanted to get you guys thoughts.

Thanks
Ken Maisano

Are you stating it has round wire locks? If so, you will not have a problem running it with .042" end play.

[frnkeore]

If it has a square corner groove, it may have been made to use double spiral locks.

[DCal]

I agree with Charlie, While its not the number that we're wanting to hear it's still OK. The round locks are usually the same wire diameter for .975, .980, .984 and .990 Lets say the wire is .072, the formula for the groove dia. is: pin diameter plus .072 plus .010=1.057 Would be different for .990
This 1.057 would put more than half of the wire below the wristpin bore and when the chamfered pin pushes on the lock it tries to expand the lock into its groove instead of pushing it out of the groove as a spiro loc would. I've seen this many times and have had ProStock guys actually request it several times..

[Kenny M]

I agree with Charlie, While its not the number that we're wanting to hear it's still OK. The round locks are usually the same wire diameter for .975, .980, .984 and .990 Lets say the wire is .072, the formula for the groove dia. is: pin diameter plus .072 plus .010=1.057 Would be different for .990
This 1.057 would put more than half of the wire below the wristpin bore and when the chamfered pin pushes on the lock it tries to expand the lock into its groove instead of pushing it out of the groove as a spiro loc would. I've seen this many times and have had ProStock guys actually request it several times..

Yes it is Round wire locks. CP Says they like a maximum of .025 They are getting me the correct length pins. Like you guys stated, they said its not right, but probably would not be a problem using it. But I would rather not take the chance . It will also have a very quit exhaust system . Very rare 1968.5 Black Cougar . Thanks for all your help..

[BlitzA64]

I would imagine Trend could do that if you still need to find a supplier

[PackardV8]

I agree with Charlie, While its not the number that we're wanting to hear it's still OK. The round locks are usually the same wire diameter for .975, .980, .984 and .990 Lets say the wire is .072, the formula for the groove dia. is: pin diameter plus .072 plus .010=1.057 Would be different for .990
This 1.057 would put more than half of the wire below the wristpin bore and when the chamfered pin pushes on the lock it tries to expand the lock into its groove instead of pushing it out of the groove as a spiro loc would. I've seen this many times and have had ProStock guys actually request it several times..

Yes it is Round wire locks. CP Says they like a maximum of .025 They are getting me the correct length pins. Like you guys stated, they said its not right, but probably would not be a problem using it. But I would rather not take the chance . It will also have a very quit exhaust system . Very rare 1968.5 Black Cougar . Thanks for all your help..

Quiet exhaust? Are we thinking the extra pin-to-lock clearance is going to produce audible noise?

[pdq67]

Jack,

He might be trying to give us a hint as to who owns it???

pdq67

[Mark O'Neal]

.042 is fine.

The standard is .020 to .040...and I wouldn't ask another manufacturer about Autotec's specifications.

[Kenny M]

I agree with Charlie, While its not the number that we're wanting to hear it's still OK. The round locks are usually the same wire diameter for .975, .980, .984 and .990 Lets say the wire is .072, the formula for the groove dia. is: pin diameter plus .072 plus .010=1.057 Would be different for .990
This 1.057 would put more than half of the wire below the wristpin bore and when the chamfered pin pushes on the lock it tries to expand the lock into its groove instead of pushing it out of the groove as a spiro loc would. I've seen this many times and have had ProStock guys actually request it several times..

Yes it is Round wire locks. CP Says they like a maximum of .025 They are getting me the correct length pins. Like you guys stated, they said its not right, but probably would not be a problem using it. But I would rather not take the chance . It will also have a very quit exhaust system . Very rare 1968.5 Black Cougar . Thanks for all your help..

Quiet exhaust? Are we thinking the extra pin-to-lock clearance is going to produce audible noise?

Yes on a mechanical noise level.. I seriously doubt it, but why take the chance when you are not comfortable with something and its a easy fix.