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Discussion Starter #1
I had another thread going trying to diagnose the issue. I did a compression test and took off the passenger side head. The attached picture shows the broken piston.

So now what? I'm going to finish tearing down the engine and pulling the engine/trans from the car but then what?

Obviously it needs to be rebuilt but I started this thread because I have a budget of about $2500 and I don't think that would cover a machine shop to go through and rebuild it. So I'm looking for advise and also know I have no issue tearing an engine down but putting one back together scares the hell out of me.

Also, The GT40 heads I took off look to be in good shape so should I feel confident in them or no?
 

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Spammer Hammer
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Might be able to get away with just replacing that piston. However, it seems to me your compression numbers were a little low, but not by much. I would think a good hone and re-ring with quality rings and replace that one piston. You might be good to go. Good engine shop should be able to help decipher the best approach.
 

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Any shop you take them to will test them before committing to rebuilding them. If you are on a budget tear down the entire thing yourself and make sure there is no other damage or if that block is even reusable. Then talk to one of the local shops about a budget rebuild with you doing the assembly. There are a couple of companies out here that will take a good set of heads and a block and rebuild it using budget parts in that pricerange and they will even build the shortblock for you.
 

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When the 347 was originally built it should have been balanced meaning all of the pistons were weighed and metal was removed from the heaviest seven to match their weight with the lightest one. Rods would have received the same treatment. The guy you bought it from should have received a Balance Card showing the weights of all the individual items. I don't suppose you got that card when you bought it? You should at least make an attempt to get the card or contact the shop that did the balancing to find out how much the new piston you are going to install should weigh.
 

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First off is to find out why a chunk of the piston is missing. One possibility is that it's a hyperutectic that the ring gap was too tight that may have broken the top ring land. The other you had detonation that broke the ring land. I think you'll need to find a good shop to find the cause and fix anti that is wrong.
 

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Discussion Starter #10
I've settled on a course of action. I've finished tearing down the engine and just need to pull it out, take off the starter and drop it off at the machine shop. I've found a good one that alot of the local guys (been hitting the cruise nights) recommend. I'm going to have the block checked out and have them report back what exactly is in the engine. Once I know that we are going to discuss some options. Basically I'm hoping to sell my GT40P heads and intake. Going to start a separate thread on that though. Basically I'm going to rebuild the engine top to bottom.
 

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If you're limited on funds I'd just re-use the heads and intake for now if they're in good condition and put the money to building the shortblock right. It's a lot easier down the road to swap heads then a short block.
 
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