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Discussion Starter #1
There is a cracking problem that is becoming an epidemic, and its only among the 351 roller blocks, the F4TE. We are averaging 2-3 cracked blocks for every 10 we get in. The crack is in the same spot every single time.

The cracks are noticed easily by eye when you remove the number 2 and number 4 cam bearing. Its not a coincidence that this is the same area that is used for the spider tray hold down. You can clearly see the cracks in the picture.

A problem will arise if this crack runs, the cam bearing will lose press and the bearing will walk out quickly and its all down hill from there.

I can guarantee alot of shops will use the block, whether they overlook it or think its not a big deal. I do NOT use these blocks. If you are having your roller windsor block machined, tell your machinist you want to see this area, protect yourself.

I will answer all questions should you have any :)

 

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What causes them? Have you ever actually seen a failure from these cracks?
 

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Discussion Starter #5
What causes them? Have you ever actually seen a failure from these cracks?
No idea what causes them, its odd because the roller 302 has the same design and I do not see the cracking like the 351.

I haven't had any failures, but if a guy wants to chance it and throw 600-700 hp through the block and twist it up, I guarantee the crack will run
 

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Isn't it all the 351 Roller blocks? Making me scared. Is it possible to see the crack with the cam bearings installed? I was already planning for a Dart block over this next winter.
 
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Damn...glad i didnt buy that used 387ci stroker f4te short block lol. Thanks for the find and the info. I wonder if the NON roller blocks will be affected if converted to roller?
 

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lol....sorry im a little light headed after moving a 5.0off a trailer with no engine hoist.
 

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so a motor with lower hp should be safe?
 

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Just out of curiocity Woody- Is there anything you can do to further prevent a good block from cracking in this area? I figure the cam journals are hard to get to for chamfering...?
 

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My block is from a 93, not sure if lightning or not. I did a full inspection before assembling mine and found no cracks. Fingers crossed mine doesnt crack.
 
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