Piston wrist pin length

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ptuomov
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Re: Piston wrist pin length

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LSP wrote: Thu Feb 13, 2020 5:16 pm
ptuomov wrote: Thu Feb 13, 2020 8:14 am
LSP wrote: Thu Feb 13, 2020 7:27 am

What is the motor's intended use?
Street car, 5.0L, 93 octane pump gas, twin turbo, 8000 rpm fuel cutoff, 78.9mm stroke, probably about 800 lbf-ft torque over a fairly broad power band.
Putting Subaru pistons in a V-8?
They didn’t end up being Subaru pistons but custom pistons from another 100mm forging. The overlap between the pin and the boss is similarly short, and the pin walls are stupid thick.
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Re: Piston wrist pin length

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ptuomov wrote: Thu Feb 13, 2020 5:32 pm
LSP wrote: Thu Feb 13, 2020 5:16 pm
ptuomov wrote: Thu Feb 13, 2020 8:14 am

Street car, 5.0L, 93 octane pump gas, twin turbo, 8000 rpm fuel cutoff, 78.9mm stroke, probably about 800 lbf-ft torque over a fairly broad power band.
Putting Subaru pistons in a V-8?
They didn’t end up being Subaru pistons but custom pistons from another 100mm forging. The overlap between the pin and the boss is similarly short, and the pin walls are stupid thick.
Can you show a pic of your piston from the bottom? And how thick is it in the center?
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Re: Piston wrist pin length

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Here:
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AEC27DA5-ECC6-4C85-A85C-7FB93594F911.jpeg
05027747-8276-4F92-ABF8-249A9EB2BDFD.jpeg
369F4972-8D07-43C4-BEF7-7CAFFF685F11.jpeg
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Re: Piston wrist pin length

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How thick is it in the center?
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Re: Piston wrist pin length

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LSP wrote: Sat Feb 15, 2020 12:02 pm How thick is it in the center?
I don’t have the numbers here on the ski slopes, but it’s really thick. We wanted both ring lands to be really tall, and that allowed the crown to be really thick even in the center. From memory, something like 10mm, but I may be misremembering that.

The pin is short but 5.5mm wall thickness and 24mm diameter.
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Re: Piston wrist pin length

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It’s not quite 10mm, the thinnest part of the crown is 6.7mm/0.264” which is still very thick.
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