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Discussion Starter #1
I just purchased a "race prepped" Dart SHP 8.2 block and rotating assembly from a well known online company that sells "race prepped blocks". I have seen several positive reviews of this company on Yellowbullet. After receiving the block, I started measuring oil clearances and found them to be looser than expected and more than .0005 difference between the center and outer mains. After a phone call with the seller it was suggested to either try a different brand of bearing known to fit tighter or buy a set of .001 bearings and use a half set.They assured me that no block could ever leave their shop without shaving the caps and honing the mains to perfect specs. I decided to buy the different brand bearings and give it a try.

While waiting for the new bearings to arrive, I did some in depth measuring on the block and Crankshaft.The Molnar crank measures very consistently at the large side of the spec with almost no taper or out of round. Then I started measuring the block and found the according to my measurements the block is at least .001 over the maximum spec on some journals. .0005 over on #1 and #5, .001 on #2 and #4, and .0013 on #3.

The new bearings have now arrived and I can get the oil clearance I want (.0025-.003) but now Im concerned about proper bearing crush with the oversize bores. I have measured the bores many different ways, Bore gauge set with a good quality new micrometer, snap gauges with the same micrometer and even my high end dial caliper all say the bores are too big. What do you think?

Thanks
Ken
 

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I would look for thicker shell bearing but you will need to line hone the block more to match. I would think the block was attended for something else but sold for a std bearing.
 

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Discussion Starter #4
I would look for thicker shell bearing but you will need to line hone the block more to match. I would think the block was attended for something else but sold for a std bearing.
The block was supposed to be brand new and set up for my rotating assembly purchased from the same place. Kind of disappointing considering how much I spent.
 

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Many times buying a rotating assembly and block kit, the seller actually does no machine work themselves. What ever Dart or Brodix or Blue Print blocks did is what you get.
 

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Why would someone line hone a brand new block. The factory should have the block bore correct for the application. I would take the block to a good reputable machine shop and have them check the clearances. Unless you do the measuring all of the time it might be your methods. We are not talking about Chinese shit here.
 

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Discussion Starter #7
Many times buying a rotating assembly and block kit, the seller actually does no machine work themselves. What ever Dart or Brodix or Blue Print blocks did is what you get.
That is not what this place advertised, but lesson learned for sure. They advertise an 18 point list of everything they do to the block that seems pretty impressive but it seems it didn’t actually get done. There is no reasonable way to send this back and have it fixed by them.
 

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Discussion Starter #8
Why would someone line hone a brand new block. The factory should have the block bore correct for the application. I would take the block to a good reputable machine shop and have them check the clearances. Unless you do the measuring all of the time it might be your methods. We are not talking about Chinese shit here.
It would be a shame if Dart shipped a block that far out but also a shame if this place didn't catch it. I will do that before I contact the seller again but its been measured too many ways too many times for it to be a coincidence. I have a good local machine shop I will pay to measure the block for me. I don't have the best measuring equipment but its better than most have and I know how to use it. When I use the same equipment to measure the rods, they were all perfect and within spec.
 

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That is not what this place advertised, but lesson learned for sure. They advertise an 18 point list of everything they do to the block that seems pretty impressive but it seems it didn’t actually get done. There is no reasonable way to send this back and have it fixed by them.
I may have missed it....But assuming you purchased directly from them have you contacted them (after measuring the block itself) to ask if they are willing to help resolve the issue?
 

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I hardly ever get a dart block that doesn't vary 5-7 tenths from one end to the other on the mains, they are never .0001 over though. I fix them and charge the customer.
 

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Discussion Starter #12
I may have missed it....But assuming you purchased directly from them have you contacted them (after measuring the block itself) to ask if they are willing to help resolve the issue?
I will speak with them again after measurements are verified but I’m pretty confident they are good. I was just looking for ideas about the best way to resolve it? Take it to a local machinist and line hone properly? Will they be able to get them round again since they are so much oversized? I’m pretty certain I don’t want to run it even if the oil clearance is ok because of not enough bearing crush. What do you think the seller should do to make this right for me?

This is item number 1 on their 18 point list of things I paid for in the “race prep” package.

Check and align hone mains if needed, chamfered main parting lines
 

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Discussion Starter #13
Sucks having problems with online purchases, but here's my take on it,
Online company, "we never have a problem"..
Local machine shop would say, " bring it back, we will check it out and correct it if there is a problem...
End of story.
JMO
Agreed, lesson learned. I was just trying to save time by purchasing everything ready to go from one place. But with the online place not meeting their deadlines and now with the other problems I would have been better of ordering the block and having it shipped directly to the local machinist. Live and learn.
 

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Why would someone line hone a brand new block. The factory should have the block bore correct for the application. I would take the block to a good reputable machine shop and have them check the clearances. Unless you do the measuring all of the time it might be your methods. We are not talking about Chinese shit here.
Sorta thought the thing but dimensions on the block appears to be otherwise. The numbers are to off and irregular to be alined hone
 

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To late to do anything but take it to your machine shop of choice. pay to have them check all critical sizing. Get a quote to put things right. Contact the seller and send them a copy of the quote with the machine shops letter head on it. Tell them you want them to pay for the work quoted. If they doubt it, ask them to call the machine shop and tell the machine shop they are wrong. At least you will have peace of mind you did all you could. And you will get your block back in shape. Whatever it cost will be how much that you learned about online salesmen.
 

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Discussion Starter #16
Sorta thought the thing but dimensions on the block appears to be otherwise. The numbers are to off and irregular to be alined hone
here is a Cleveland cap that has been cut and align honed next to the one off the Dart block that they told me was cut and align honed. Sure doesn’t look like it.
 

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Discussion Starter #18
Just for shits and giggles I put the caps on my machined Cleveland block and started measuring to test my tools and my own abilities. All 5 measured almost exactly the .0005 over minimum spec that the machinist noted in the paperwork.im still gonna have the Dart block double checked but it’s not looking good.
 
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