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The difference in the Mod and Coyote cranks is the #5 thrust main. This is a shenanigan you will be better off not playing around with. Manley will sell you a new 4340 forging with full radius journals on both rods and mains for a grand. They also sell complete rotating assemblies with crank, rods, pistons, and rings fully balanced and ready to go. This is by far the short way home.
 

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67 Fairlane 500XL. Planning on a 32 valve 4.6, 4r70w swap
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Discussion Starter · #42 ·
The difference in the Mod and Coyote cranks is the #5 thrust main. This is a shenanigan you will be better off not playing around with. Manley will sell you a new 4340 forging with full radius journals on both rods and mains for a grand. They also sell complete rotating assemblies with crank, rods, pistons, and rings fully balanced and ready to go. This is by far the short way home.
Definitely leaning towards this... Seems like a lot of coin at first, but in the long run I'm betting it gives you the best bang for your buck. Less heartburn with mismatched parts too.
I'm trying to decide what compression ratio I should be aiming for as well. I don't want to go with dished pistons as I may not get to add boost for some time and want a reasonable na runner in the meantime. Should I stick with stock CR? Can I go with flat tops and still add (a little) boost later? I want to run pump gas obviously and don't want a ton of boost for longevity. 6-8 pounds tops. Thoughts?
 

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You want a c/r between 8:1 and 9:1 for a boosted engine and 10:1 for a n/a engine. You can fudge the numbers to your heart's content, but when you are all done, the reliability will be within those c/r's. Because you are initially an n/a build, I would consider going with Manley for everything. Later if you put a blower on the engine I would use Gibtec pistons. If you do a piston swap later for a boosted build, it means pulling the engine down to get the rotating assembly rebalanced.
 
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