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10k miles. I measured piston to wall and with bore gauge we are .002 off and with feeler approximately.003 or .004
1) When measuring jugs and piston fit, torque plates are a must. Not a recommendation.

2) if you can get a .003 blade into that jug and piston w/plates, its time for a machine shop.

3) Never trust reputation from a machine shop. Check everything once its back on your bench. **** happens, even in the best of regulated shops.

Past that, measuring jugs is 1/2 technique and 1/2 tool quality. Same goes for pistons, fact is some pistons are very difficult to measure without a jig. A blade in-between the piston skirt and the jug is your best bet for a done at home job.

All of these are only as good as the person using them. And if you look closely, none of the mic's are set up to measure pistons atm
267698


But this right here doesn't require more than a entry level of skill to sort out. Just a good set of 12 inch blades that go all the way down to .001 But you do have to have torque plates. There is just no way to do it correctly without them.

267699



So with the set up spec on a TC jug/piston being .0014 to .0025, you are headed back to the machine shop. I might mention that with the piston skirts being so short on TC's, there is very little margin for error. The discard point is .003.

So I'll say this one more time. You need to to seriously consider a crate motor. Even with that you are looking at dropping the oil pan to either clean of replace it and if it has an oil cooler, all of that needs to be disassembled and cleaned with any hoses and the cooler taking up residence in the waste bin.
 

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Most likely 2618 material on the piston.They expand more than 4032 forgings.Probably was too tight of a fit and with the increased heat of running hard the piston expanded enough to squeeze the oil out of the piston to cylinder clearance.
Forged pistons need to be set up on the loose side to allow for heat expansion. Set at 0.0035 to 0.004 in. will generally, (meaning correct fuel, tune and good oil) prevent what happened.

Stock type cast pistons can be run much tighter.Cast pistons work fine if the compression or RPM' s aren't too high.


Opinions are like assholes...everyone has one.


Good luck. :rolleyes:
 

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Discussion Starter #43
1) When measuring jugs and piston fit, torque plates are a must. Not a recommendation.

2) if you can get a .003 blade into that jug and piston w/plates, its time for a machine shop.

3) Never trust reputation from a machine shop. Check everything once its back on your bench. **** happens, even in the best of regulated shops.

Past that, measuring jugs is 1/2 technique and 1/2 tool quality. Same goes for pistons, fact is some pistons are very difficult to measure without a jig. A blade in-between the piston skirt and the jug is your best bet for a done at home job.

All of these are only as good as the person using them. And if you look closely, none of the mic's are set up to measure pistons atm
View attachment 267698

But this right here doesn't require more than a entry level of skill to sort out. Just a good set of 12 inch blades that go all the way down to .001 But you do have to have torque plates. There is just no way to do it correctly without them.

View attachment 267699


So with the set up spec on a TC jug/piston being .0014 to .0025, you are headed back to the machine shop. I might mention that with the piston skirts being so short on TC's, there is very little margin for error. The discard point is .003.

So I'll say this one more time. You need to to seriously consider a crate motor. Even with that you are looking at dropping the oil pan to either clean of replace it and if it has an oil cooler, all of that needs to be disassembled and cleaned with any hoses and the cooler taking up residence in the waste bin.
Do you know where I can buy some used torque plates. I鈥檝e chunked the case and jugs etc and starting with new set and case etc. we did completely tear down and wash every inch of every item all the way down to the smallest screw.
 

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Discussion Starter #44
1) When measuring jugs and piston fit, torque plates are a must. Not a recommendation.

2) if you can get a .003 blade into that jug and piston w/plates, its time for a machine shop.

3) Never trust reputation from a machine shop. Check everything once its back on your bench. **** happens, even in the best of regulated shops.

Past that, measuring jugs is 1/2 technique and 1/2 tool quality. Same goes for pistons, fact is some pistons are very difficult to measure without a jig. A blade in-between the piston skirt and the jug is your best bet for a done at home job.

All of these are only as good as the person using them. And if you look closely, none of the mic's are set up to measure pistons atm
View attachment 267698

But this right here doesn't require more than a entry level of skill to sort out. Just a good set of 12 inch blades that go all the way down to .001 But you do have to have torque plates. There is just no way to do it correctly without them.

View attachment 267699


So with the set up spec on a TC jug/piston being .0014 to .0025, you are headed back to the machine shop. I might mention that with the piston skirts being so short on TC's, there is very little margin for error. The discard point is .003.

So I'll say this one more time. You need to to seriously consider a crate motor. Even with that you are looking at dropping the oil pan to either clean of replace it and if it has an oil cooler, all of that needs to be disassembled and cleaned with any hoses and the cooler taking up residence in the waste bin.
Crate engine takes all the fun out of it and then I鈥檇 be tearing into it too upgrade items. I鈥檝e learned so much this last year and it鈥檚 been a blast. Just to think this all started with a welded shifter shaft.
 

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Discussion Starter #45
1) When measuring jugs and piston fit, torque plates are a must. Not a recommendation.

2) if you can get a .003 blade into that jug and piston w/plates, its time for a machine shop.

3) Never trust reputation from a machine shop. Check everything once its back on your bench. **** happens, even in the best of regulated shops.

Past that, measuring jugs is 1/2 technique and 1/2 tool quality. Same goes for pistons, fact is some pistons are very difficult to measure without a jig. A blade in-between the piston skirt and the jug is your best bet for a done at home job.

All of these are only as good as the person using them. And if you look closely, none of the mic's are set up to measure pistons atm
View attachment 267698

But this right here doesn't require more than a entry level of skill to sort out. Just a good set of 12 inch blades that go all the way down to .001 But you do have to have torque plates. There is just no way to do it correctly without them.

View attachment 267699


So with the set up spec on a TC jug/piston being .0014 to .0025, you are headed back to the machine shop. I might mention that with the piston skirts being so short on TC's, there is very little margin for error. The discard point is .003.

So I'll say this one more time. You need to to seriously consider a crate motor. Even with that you are looking at dropping the oil pan to either clean of replace it and if it has an oil cooler, all of that needs to be disassembled and cleaned with any hoses and the cooler taking up residence in the waste bin.
The jugs and pistons I can gently slide a .0005 blade between without torque plates. I have bore gauge and micrometers I just need to find me a set of torque plates I guess.
 

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The jugs and pistons I can gently slide a .0005 blade between without torque plates. I have bore gauge and micrometers I just need to find me a set of torque plates I guess.
You sure that's not .005?

And the way you do that is to lay the blade in the jug with some hanging out of both ends. Then slide the piston in so that the skirt is oriented in the jug the same way it rides when assembled, but with the blade between the skirt and jug. Then grab the blade from both ends and see if it will slide back and forth with ease. Once you find the blade that wont slide without dragging the piston along, the next thinnest blade will be your clearance. But, you will need torque plates to get a true measurement.
 

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Crate engine takes all the fun out of it and then I鈥檇 be tearing into it too upgrade items. I鈥檝e learned so much this last year and it鈥檚 been a blast. Just to think this all started with a welded shifter shaft.
There are less expensive ways to get that education.
 

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Do you know where I can buy some used torque plates. I鈥檝e chunked the case and jugs etc and starting with new set and case etc. we did completely tear down and wash every inch of every item all the way down to the smallest screw.
How did you wash the crank pin? Bottom side of the windage tray?

Smaller than a 110, you can use these.
https://www.georges-garage.com/product/torque-plates-3750-3938/

I've seen reconditioned plates on Ebay for like $200, but I wouldn't trust them.
 

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I've seen reconditioned plates on Ebay for like $200, but I wouldn't trust them.
1) Why would you need to recondition them unless they were gorilla'd on.
2) How are they reconditioned? Milled flat again?

Sent from my SM-G965U using Tapatalk
 

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Discussion Starter #53
How did you wash the crank pin? Bottom side of the windage tray?

Smaller than a 110, you can use these.
https://www.georges-garage.com/product/torque-plates-3750-3938/

I've seen reconditioned plates on Ebay for like $200, but I wouldn't trust them.
I went ahead and got new plate and sent crank off to have serviced and installed int9 Timken and case. They. Are also cutting out some cam reliefs for me since I went with a older style case already set up for the aTimken bearing.
 

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1) Why would you need to recondition them unless they were gorilla'd on.
2) How are they reconditioned? Milled flat again?

Sent from my SM-G965U using Tapatalk
And how would you know that they were bad?

I'm thinking they are prolly Chicom knockoffs and that they are milled to remove the name of whom ever was being ripped off.

Past that, I guess a tread could be pulled, or they could have been found rusting in a junk pile.
 

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And how would you know that they were bad?

I'm thinking they are prolly Chicom knockoffs and that they are milled to remove the name of whom ever was being ripped off.

Past that, I guess a tread could be pulled, or they could have been found rusting in a junk pile.
Roger that.

Sent from my SM-G965U using Tapatalk
 
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