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#1
02-19-2014, 08:39 PM
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Question on piston damage
Been holding onto these pistons for a while I was thinking about using them for a build. like a dummy I just had them in a box no padding. did I screw up storing them improperly or are these dings trivial v
   Sent from my iPhone using Tapatalk Last edited by Brewster7376; 02-19-2014 at 09:08 PM. |
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#2
02-19-2014, 09:32 PM
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Budget build with a little cleanup, might be O.K. Are these stock? .030? What engine?
I'm partial to not using anything that might be a problem later. I guess it depends on your cash flow and luck. |
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#3
02-19-2014, 09:38 PM
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Building a motor for a class I'm in if it turned out ok was thinking about putting in my formie
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#4
02-19-2014, 09:39 PM
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455 cast pistons 030 over
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#5
02-19-2014, 11:21 PM
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If you have a good instructor, then he should be able to tell you what you can and can't do with that damage. It seems pretty superficial, but it all depends on how well you prep your build. Cast pistons are pretty forgiving, so I don't see much of a problem trying to use them. I would be careful and make sure that the block they get used in will/can be bored to match the pistons after they are cleaned up and the nicks taken care of.
If it is for your learning experience, I say go ahead and try it out, just don't spend a lot of money on it. I would hate to see a serviceable block be trashed by marginal pistons. That being said, the pistons could be turned down to .020 over, if the block is still standard then you would only need a matching bore. Everyone could be happier and you would have a nice power unit. |
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#6
02-20-2014, 12:34 AM
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Quote:
__________________
---------------------------- '72 Formula 400 Lucerne Blue, Blue Deluxe interior - My first car! '73 Firebird 350/4-speed Black on Black, mix & match. |
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#7
02-20-2014, 09:38 AM
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Get a fine cut file and make sure the rings move freely in the grooves all the way around. File the high spots on the nicks flush with the area around it. As long as the vertical in groove ring clearance isn't worn from previous use. Use em and go have fun.
One can get anal retentive on this but if you have seen the shape of some pistons pulled out of perfectly good engines and running great............................. |
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#8
02-20-2014, 09:50 AM
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The rings feel nice and tight I used some fine paper folded to take away any high spot in the groove rings don't catch on any spot. But are still tight
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#9
02-20-2014, 05:07 PM
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Quote:
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#10
02-20-2014, 05:28 PM
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rings should be able to move freely around in the groove.
I had a set of pistons put on rods and the "machinist" clamped down on the ring area and I had to file out a couple spots on a few pistons to get the rings installed properly. |
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#11
02-21-2014, 12:17 AM
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Ken's recommendation of a file is what is needed. Sandpaper takes a little off both the high spots and the low spots, and doesn't really accomplish anything. A decent file will float around the ring land until it comes across a high spot, and you will know it when it finds one - easy to remove the tight areas.
__________________
Mick Batson 1967 original owner Tyro Blue/black top 4-speed HO GTO with all the original parts stored safely away -- 1965 2+2 survivor AC auto -- 1965 Catalina Safari Wagon in progress. |
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#12
02-21-2014, 02:14 AM
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Quote:
__________________
---------------------------- '72 Formula 400 Lucerne Blue, Blue Deluxe interior - My first car! '73 Firebird 350/4-speed Black on Black, mix & match. |
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#13
02-21-2014, 08:38 AM
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Even if the rest of the piston is perfect the compression ring groves need to be checked by incerting a new ring and checking the verticle clearance.
If you find more than .004" due to ware, then dont expect to get good ring seal/ low blow by numbers!!
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#14
02-21-2014, 08:39 AM
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I think I'm just going to get a new set of pistons don't want to chance anything
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