Ring gap ...
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From: Armpit of East TX
Ring gap ... Building a 408, trying to decide on ring gap.
Following the card advice, what would be the result of keeping it on the tight side.
I'm aiming for around 12:1 compression in a daily driven truck, might see some nitrous use. 200-250 absolute MAX!
Following the card advice, what would be the result of keeping it on the tight side.
I'm aiming for around 12:1 compression in a daily driven truck, might see some nitrous use. 200-250 absolute MAX!
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From: Mefis
Originally Posted by Flyer
Building a 408, trying to decide on ring gap.
Following the card advice, what would be the result of keeping it on the tight side.
I'm aiming for around 12:1 compression in a daily driven truck, might see some nitrous use. 200-250 absolute MAX!
Following the card advice, what would be the result of keeping it on the tight side.
I'm aiming for around 12:1 compression in a daily driven truck, might see some nitrous use. 200-250 absolute MAX!
http://www.jepistons.com/pdf/2005-proseal.pdf
Check out page 12. What transmission are you going to run behind the 408?
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Taht info's kinda contradicting the sheet in the rings.
Mahle says up to 150 shot go with .006/.007
JE says moderate nitrous apps go with .005/.0055
Mahle over 150 shot go with .008/.009
JE RACE only nitrous use .007/.0073
Mahle says up to 150 shot go with .006/.007
JE says moderate nitrous apps go with .005/.0055
Mahle over 150 shot go with .008/.009
JE RACE only nitrous use .007/.0073
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From: Mefis
Originally Posted by Flyer
Taht info's kinda contradicting the sheet in the rings.
Mahle says up to 150 shot go with .006/.007
JE says moderate nitrous apps go with .005/.0055
Mahle over 150 shot go with .008/.009
JE RACE only nitrous use .007/.0073
Mahle says up to 150 shot go with .006/.007
JE says moderate nitrous apps go with .005/.0055
Mahle over 150 shot go with .008/.009
JE RACE only nitrous use .007/.0073
I'll bring it back to the top for you. Maybe you can get some more suggestions.
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From: Mefis
Originally Posted by Flyer
What do you mean by per inch of bore?
What would happen if they were to tight for my application?
What would happen if they were to tight for my application?
The little table on JE's site gives you a number to multiply the bore size by. For example, JE recommends a minimum gap of .0050" per inch of bore for street turbo/moderate nitrous use.
So, your 408 has a bore of 4.060" If I remember my numbers correctly.
Multiply your 4.060" bore by .0050" gap per inch and you get: .0203" ring end gap for the top ring, if my math is correct.
If you were to use too tight of a ring end gap, under high loads, like when using the nitrous, the heat in the cylinder would cause the rings to grow and butt together. That would score the cylinders. Thats no good.
