Piston dome question?

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The picture is a LOT bigger than what the site let me post. That figures.
 
Your bore on the block you intend to use needs to be 4.04 for a std 2322 piston.
If you have Any cylinder wear, you will have too much wall clearance. Those pistons
are made "small" (like 4.0340) to fit so you will have .oo6 when put it in a 4.040 hole.
.006-7 was normal back then but through the years (40) experience has shown us
that they really like .005 better. I have a set of 8 ashtrays with the tops cut before we
measured the block. Went with .030 over at extra expense....and ended up cutting the tops off because of the gas...back in the day-----mid 70's.
Pistons are still in use today...
 
Zyglo #ZA-70 Crack Detection

Liquid Penetrant Detection w/Ultra-Violet Black Light

Spotchek Visible Red Dye Test Kit

This is the only way to have 'surface cracks' in Aluminum Pistons checked.
 
Rusty, Rusty...don't blow a gasket, dude!
It's a costly decision. Just want to make sure it's the right one.
I asked Tony because he's the guy doing the machine work on the engine. And actually, I emailed him before I even posted here.
What I plan on doing is cleaning up the remaining 6 and checking them all. For what it's worth, I'm fairly certain it's not a crack, but as a trained fluorescent penetrant inspector, should be a piece of cake to Zyglo it and confirm...but that's not my immediate concern. What is, is the worry that the chunk might break off even if it's a fault line or forging fold.
I will try to blend it out as most of you have suggested...what do I have to lose, right?
I can confirm these things are over-built, it's a big chunk of aluminum there.
Thanks for the help, guys. Will keep you all posted.
 
Captainkirk said:
Rusty, Rusty...don't blow a gasket, dude!
It's a costly decision. Just want to make sure it's the right one.
I asked Tony because he's the guy doing the machine work on the engine. And actually, I emailed him before I even posted here.
What I plan on doing is cleaning up the remaining 6 and checking them all. For what it's worth, I'm fairly certain it's not a crack, but as a trained fluorescent penetrant inspector, should be a piece of cake to Zyglo it and confirm...but that's not my immediate concern. What is, is the worry that the chunk might break off even if it's a fault line or forging fold.
I will try to blend it out as most of you have suggested...what do I have to lose, right?
I can confirm these things are over-built, it's a big chunk of aluminum there.
Thanks for the help, guys. Will keep you all posted.
Click to expand...

I get that, but YOU and only you have the answer. You have the piston. Stop cryin about it on the internet and get to polishin, I bet that joker cleans up from what I can see. lol
 
Caint hurt to try. Be gentle at first till you get the feel for it.
 
I think you need to address the detonation issue that made all those little "pocks" ..

Detonation likely vaporized all those liitle marks,, you'll likely find those marks predominately on the pistons circumference,, and mostly oppostie the sp plug position..

The pressure caused during detonation can be catastrophic,, and,, with that little "chunk" ,, (that I think is a crack),, could be blown out sideways from the valve pocket,, by the tremendous pressure of detonation..

I don't think I'd use that piston,, and certainly knock the domes off them, if I did..( and I have) ..

Here's a link to understanding detonation and the consequences.. then a link to a detonaton damaged piston,, that should look familiar..

http://www.enginelogics.com/engine-detonation/

http://www.forabodiesonly.com/mopar/showpost.php?p=1970302464&postcount=16

hope it helps..
 
inertia said:
I think you need to address the detonation issue that made all those little "pocks" ..

Detonation likely vaporized all those liitle marks,, you'll likely find those marks predominately on the pistons circumference,, and mostly oppostie the sp plug position..

The pressure caused during detonation can be catastrophic,, and,, with that little "chunk" ,, (that I think is a crack),, could be blown out sideways from the valve pocket,, by the tremendous pressure of detonation..

I don't think I'd use that piston,, and certainly knock the domes off them, if I did..( and I have) ..

Here's a link to understanding detonation and the consequences.. then a link to a detonaton damaged piston,, that should look familiar..

http://www.enginelogics.com/engine-detonation/

http://www.forabodiesonly.com/mopar/showpost.php?p=1970302464&postcount=16

hope it helps..
Click to expand...

Thanks for the links!
I agree that detonation probably caused the craters. Compression was in the 11-11.5 range in this motors' last life, and probably in the 12.5:1 range when I first got it (pre-cc'd chambers). I'm going to take whatever steps it takes (cc'ing heads more or dome milling) to drop it down into the 10-10.5:1 range on this current build...that is, if the damage can be polished out.
 
Well, thanks to you forum guys giving me some great advice (and a boot in the ***...thanks, Rusty!) I decided to see if this piston was junk, or if it was all in my head. I'm happy to say it's working out just fine, thank you very much!

I chucked said piston in a vise (between two cardboard cushions, of course!) and having it cinched down as such, dragged out the grinder with a fine grit RoLoc disc....

16666846965_54f8b4b7a8_z.jpg


Close-up of the, ummm...implement
16640926696_f7bfe35f29_z.jpg


Throwing caution to the wind, I turned the disk on edge and started 'hogging out' out the suspect area across the crown and down the valve relief cutout...
16479290338_ce0f5e6d5f_z.jpg


....and then tapered the edge of the cutout to blend it...
16479966168_a7bfb0f4b5_z.jpg


16045242434_c0acb7d032_z.jpg


16045265914_d7d3f24317_z.jpg


....followed up by a trip to the deep-sink with some running water and 220 wet-or-dry to smooth the tooling marks...

16666566722_6b798e81cd_z.jpg


....and finally, a hit with the polishing wheel.
16460289977_2ed2632bee_z.jpg


As you can see in this final photo, there is still a hint of the flaw on the face of the valve relief....
16045297934_d9780c74ef_z.jpg


...but not any more! I stopped taking pictures at this point, but hit the pocket again until the line is virtually invisible. Then I went to work on the other valve pocket and dome. If not for the craters, this thing would look like a new piston dome! I will show you some pictures when I'm finished.
Suffice it to say I'm extremely pleased! There was, and is, PLENTY of meat on these domes.
I'm not done yet, and still have 7 other pistons to clean and polish yet...who knows what might turn up on those?
But for a quick half-hour's work, I think it came out pretty nice.....
Crack? What crack?:cheers:
 
Hell yeah. Sometimes you just gotta ignore the haters. Good job.
 
Es muy excellente'

Never loose faith in the 'old' Heavy Bastard TRW Pistons.

They are built like a Brick **** House.
 
69 Cuda 440 said:
Es muy excellente'

Never loose faith in the 'old' Heavy Bastard TRW Pistons.

They are built like a Brick **** House.
Click to expand...

Yeah...I think you told me that! And you were right! I have no qualms about using that piston now, and planning on cleaning and polishing the others as well.
Sometimes all we need is a slap in the face and a boot in the *** to get going!

And now for something completely different:

Two questions......

1) Is there any sort of treatment or coating that can/should be done to the domes after being cleaned and polished?

2) Is it acceptable to use a metal polish such as Flitz to polish the domes once cleaned? This is a non-abrasive polishing compound, but I'm pretty sure from the odor it contains ammonia and who knows what else...can this damage or weaken a piston dome? I know, sounds stupid, but gotta ask before I do it.
 
Yes, they can be thermal coated. That's actually shown improvements on the dyno. It ain't cheap though.
 
I don't know of any that do. Some have coated skirts, but none I know of have coated heads. That is something you have to get done. It works though, I know that.
 
Captainkirk said:
Yeah...I think you told me that! And you were right! I have no qualms about using that piston now, and planning on cleaning and polishing the others as well.
Sometimes all we need is a slap in the face and a boot in the *** to get going!

And now for something completely different:

Two questions......

1) Is there any sort of treatment or coating that can/should be done to the domes after being cleaned and polished?

> You don't have to coat the Piston Domes with anything. They will be fine.

2) Is it acceptable to use a metal polish such as Flitz to polish the domes once cleaned? This is a non-abrasive polishing compound, but I'm pretty sure from the odor it contains ammonia and who knows what else...can this damage or weaken a piston dome? I know, sounds stupid, but gotta ask before I do it.


> As long as you use a 'non-abrasive' polish, you will be fine.

> Just don't over do it. Try not to remove any material.
Click to expand...

It never hurts to ask questions..........
 
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