393 Windsor
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Mountain Pass
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393 Windsor
Deciding weather or not to build a 393 out of my 351. Been on two compression calculators and they tell me exactly opposite info. my question is what pistons to use for about a 9.2 to a 9.5 compression ratio. Any thoughts?
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Cargo Master
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For a 393 the piston that you'll be using is the same as one for a 302 and this can make finding a piston with a low enough compression ratio a little tough. On most of the 393's that I've done I just use the cast Silvolite 302 rebuilder piston for engines from the mid '70's. I can't remember exactly where it ends up but it typically gives 9:1 or a little more.
KB shows a piston(KB364) in their catalog for a 393 built with a stock rod having a 22cc D shaped dish. That gives an advertised compression ratio of 10.4:1 with a 55cc chamber, 9.9 with a 60cc(early 351W head) and 9.5:1 with a 64cc and 9.1 with a 69cc chamber. Even if you use a different piston that gives some idea of the amount of dish that you'll need.
KB shows a piston(KB364) in their catalog for a 393 built with a stock rod having a 22cc D shaped dish. That gives an advertised compression ratio of 10.4:1 with a 55cc chamber, 9.9 with a 60cc(early 351W head) and 9.5:1 with a 64cc and 9.1 with a 69cc chamber. Even if you use a different piston that gives some idea of the amount of dish that you'll need.
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Mountain Pass
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OK the 393 idea is gone. I would like to build a 351 with a little more hp and torque that stock. What are my options and still run 87 octane pump gas? I don't think at 9.5 to one CR I can do that.
FTE Legend
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GT40 heads and a 5.0HO ish cam on an otherwise stock bottom end would make around 300hp/380tq.
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FTE Legend
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Stock piston, this motor has a static CR of 8.8:1 with the factory heads, GT40s somtimes have slightly smaller chambers but not that much(measure so you know).. maybe only a couple cc's, so CR will only raise to about 9:1.
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Mountain Pass
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Maybe I'm looking into this to far. What is a good quench for a 351W. Im figuring mine at .068 with .041 gaskets. Stack height(?) is 9.476 with the pistons I would like to use. Stack height is 1/2 stroke + rod length and compression height if I'm not wrong. so I'm guessing I need to deck something.
Cargo Master
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Quench
Maybe I'm looking into this to far. What is a good quench for a 351W. Im figuring mine at .068 with .041 gaskets. Stack height(?) is 9.476 with the pistons I would like to use. Stack height is 1/2 stroke + rod length and compression height if I'm not wrong. so I'm guessing I need to deck something.
Cargo Master
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People read too much into quench just like rod/stroke ratio. If you start out with a little more and the engine runs for a while, carbon builds up on the piston top and the deck what does the quench end up being?
3rd Gear
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From: Madisonville tn
This is my setup.
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You should post a 2 minute video!
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