Posts: 628
Threads: 40
Joined: Jun 2013
RT K_line Wrote:I only need 15 minutes to find a decent set of grill surrounds he has stashed away lol.
I have 2 restored sets in the rafters restored by AllTrim. Those ain't leaving my slimy hands.............
67 Coronet 500 - 9.610 @ 139.20 mph
Owned Since 1981
Daughter's Car
67 Coronet 500 Street Car with AC
13.300 @ 101.75 mph
69 GTX clone - build in progress........
Posts: 39
Threads: 4
Joined: Jan 2015
Great input guys!
But at first I thought detonation must be the cause. Now, ring gap sounds "good" too...
Or a combination of things.. You guys get me confused ;-)
I will share this input with the shop.
But what about that crack in the cilinder? Because of all of the friction that went on? Or shaking movement of the piston?
Posts: 39
Threads: 4
Joined: Jan 2015
Posts: 4,336
Threads: 91
Joined: Jan 2013
I really got something going here!
I was just putting in a vote for piston ring gap. It really looks like a ring got too big and caused the wear spots on the cylinder wall. As far as the pock marks, they look more like sharp marks from piston fragments battering itself to death. I always thought detonation would be smoother marks.
The crack was most likely from excessive heat, or pressure the expanded ring caused by digging into the wall, or a combination of both? If it's a detonation problem, we should see it on other pistons as well. At least I would think so.
Now... as far as my parts go, god help the person who lays a hand on my stash of grill surrounds. LOL Let's just say I have enough for all of my cars...
President, New England chapter of Coronetaholics anonomous.
Posts: 244
Threads: 2
Joined: Jan 2013
Stargazer Wrote:....But what about that crack in the cilinder?
Good question, one that I was wondering about as well.
You state its a 440 and it has been "bored". You don't say "how much" and if a SONIC test was done prior to boring the block. Many blocks have excessive core shift from the factory and can't SAFELY be bored a large amount without first verifying wall thickness with a sonic test. So, what I'm trying to say is if it was bored without checking it, you may have had very thin cylinder thickness in that particular area which could then rupture easily. Especially with a ring that was expanding due to the ends butted up against each other with no place to go. Just a possibility.
Posts: 244
Threads: 2
Joined: Jan 2013
ws27 Wrote:..If it's a detonation problem, we should see it on other pistons as well. At least I would think so.
....LOL Let's just say I have enough for all of my cars...
Your first sentence - Agree
Your second sentence - You have enough right now, but that is only until you buy more cars, and we all know that is inevitable.
Posts: 175
Threads: 15
Joined: Aug 2015
The detonation will cause excessive heat build up in the cylinder causing the ring to butt together. A slight vacuum leak in that cylinder may have contributed to the failure of only one piston. JMO
Posts: 4,336
Threads: 91
Joined: Jan 2013
Mopars & Missiles' Wrote:Your first sentence - Agree
Your second sentence - You have enough right now, but that is only until you buy more cars, and we all know that is inevitable.
I'm really trying to quit... but they keep finding me!
President, New England chapter of Coronetaholics anonomous.
Posts: 6,798
Threads: 474
Joined: Jan 2013
ws27 Wrote:I'm really trying to quit... but they keep finding me!
"They" ? The cars? You haven't been going to your meetings have you.
The Idaho Andy
OL Blue is scared of Max
Posts: 39
Threads: 4
Joined: Jan 2015
About piston fragments, they didn't find anything back of those fragments!?
Is it possible these pieces where smashed so small, to leave through the exhaust port?
