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Discussion Starter #1
Here's some pics of my #1 piston.
Top ring is completely shattered, biggest peice is an inch, most much less.
A third of the second ring is gone, too.
The piston, including both ring groove, is fine, no apparent damage at all.
The cylinder looks fine, too, jusy kinda old.
Other 7 were good, bearings were fair, bout half the rod bearings were showing some copper on the bottom, a few on the top, and were loose in the rods. Cranks still in, but feels "loose" too, nothing out of the ordinary.

Why would a single piston in an otherwise normal old engine shatter both it's rings?

There's no sign of detonation or anything like that, even the plug looks ok, just a lil darker than the others. There'sa lotta fresh carbon in all the chambers and piston tops, considering it was all clean 700 miles ago, so she was do for a going thru (that she shoulda got last winter!).

Car ran good, other than spitting a ton of oil out the breathers at high rpm.
 

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wow Jim that does explain the oil but not why it happened. Glad she didnt blow when we took that ride to town last week. Now Git R Dun :)
 

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I know b/c I've done it!!

Whoever installed that piston missed getting it in the first time and broke it! And unknowingly went ahead and installed it

My bad, but I caught mine and it was a week getting another .060" over 409 "W" motor top ring!!

pdq67
 

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Kinda looks like the last motor I blew up. :D But I knew it was going and wasn't going to save it. The only thing is I had 7 out 8 broken top rings and 5 broken 2nd rings. It still ran strong the last 3-4 months. (other than blowing oil out the breathers to) Until I spun a bearing at over 6k doing a real l-o-n-g burn out. :thumbsup: I never did find the problem on mine either. Although I suspect it was detonation in my case because of the carnage. I had some issues with my MSD and knew from the blow by it was starting to go. At least you found it early. :) Did you use file fit rings? Any chance the ring gap was too tight?
pdq67 makes a good point too all else being said.
 

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Discussion Starter #6
Wow, the Funkmiester LIVES!
You made it thru that blizzard and back to Georgia than?

Funny thing is this has been like that for a LONG LONG time. I've fought blowby out the breathers the entire 6 years I've owned the car! It's always run "fine" I've never done a compression check, just too much hassle to hook up the guage around the headers... always blamed the drips on the old M/T valve covers, with their breather holes right over the rocker arms...

Who'da thunk it... if I'd bothered to do a comp check, I coulda had some "stroker fun" FIVE years ago!

Remind me after this rebuild to do a baseline comp check for the record!
 

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Discussion Starter #8
Bummer you got stuck in illinois.... sorry I delayed your leaving, but the garage time was fun!

Leanig hard on the 383... talked to a machine shop today, less than 20 minutes from my house and he said all the right things (including asking me is I "REALLY" wanted to stroke a #'s matching motor...) His shop pricing was good, and he not only knew what a torque plate is, but has them and uses them. Talked to one guy at another shop, recommended by a friend, they didn't even OWN a SBC torque plate and didn't consider them nessesary!

Waiting on a quote for the hardware from the shop, and figure I'll take em my block Thursday, should have it completely stripped by then.
 

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thats what ya get for having mudflaps that drag on the ground, the excess friction must have done that cylinder in :)
 

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Discussion Starter #10
just thought I'd add an update. The shop has had my block for 2 weeks now. She needed and got a line hone. Needed and got an .030" overbore. Going in there tomorrow morning, bring him my heads to do too.
New rotating assy should be in. Can't wait to see it!
And yes, she's gonna be a 383... scat nod iron crank, 6" i-beam capscrew rods, srp forged slugs, 16cc inverted dome.
 

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Jim,

How much blowby wee you getting on your car. I saw in another post that you go thru a qt every 4 hours at 75. Has it always been that bad or gotten worse over the last year or so????

I have moroso covers (breather on back pass side) and when I start it up(and run it hard) I get oil thru my breather. Enough where you smell the oil burning off the headers as you sit in the car.

I too blamed my valve covers, but now you got me thinking? :confused:

Greg
 

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Discussion Starter #13
Well Greg, as you read in the other post, with the pvc hooked up, I never "saw" any blowby. It for sure was RPM related, and I think it was gradually getting worse, cause I've had some oil out the breathers for six years. Then on the other hand, those 2 broken rings sure didn't look gradual, and the other 7 pistons didn't have any radical problems but did show signs of ring leakage.

Bout all I know for sure is in a couple weeks, she'll be tight as a drum and near 50 cubes bigger.

I really hope I manage to not be lazy... and after I get 500 miles on the motor, pop the headers off so I can record a baseline compression check.
 

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Discussion Starter #14
Heard from the machine shop today, my stuff is ready to pick up!
Total Damage is $2601.00 for:

Hot tank block and heads
"adjust" and stud main caps
Align hone
bore .030" and hone with torque plate
Freeze plugs, crank keys, cam, main, & rod bearings
Scat nod iron internal balance 3.75" crank
Scat 6", 7/16 capscrew I beam rods
SRP 4.030" 16cc inverted dome forged pistons
Speed Pro moly rings set 1/16 1/16 3/16
Hone pin bores and pistons for proper pin clearance
Check main and rod clearances
Relieve 327 block for stroker clearance
Balance rotating assembly
check valve guide clearances
3 angle valve job
Viton positive valve seals
verify installed ht, seat and max lift spring pressure
check and adjust bellhousing runout within .005
install new pilot bearing

Tomorrow night, I'll get it all home, wonder how long it will take me to put it together?
 

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JimM said:
Tomorrow night, I'll get it all home, wonder how long it will take me to put it together?
If it were me, I'd be up all night in the garage working on it!
Sounds good Jim! I must admit I'm a little jealous. That's motor is going to to be sweet.

What's your CR going to be?

If you can, give us some car part porn tomorrow.
 

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Discussion Starter #16
car part porn will be up tonight!

CR will be around 9.7:1, will know for sure once I double check head cc's.

Current cam is comp 270h, should I keep it or go with something else?
After some serious grunt, revving over 6k not required.
 

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Discussion Starter #18
For now, I'm running 3.08. we'll see how it does with the overdrive, my rpm @ 75 mph will be about 1900!

Here's the eye candy you guys asked for. Check out how they relieved the bottoms of the cylinders for the stroker, strangely, he didn't put a mark on the pan rail. The pistons and rods are suitable for framing!
 

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Looks good Jim! When you starting to build?
 
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