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KnighTT KnighTT is offline
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Default Correcting 9.5:1 back to stock CR. - 09-10-2020, 07:20 PM

So, If I picked up a set of JE pistons with the 9.5:1 compression, you can correct CR back to 10.2:1 when you have your head decked, right?

I just don't want to pay for the CP pistons at $1100+ just because they are set to 10.2:1.

I mean I'm going to get the head worked on anyways.

Pros, cons, remedies?
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greg_e greg_e is offline
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Default 09-18-2020, 10:08 AM

You can’t add more material to the head to increase compression. CR is mainly done through the pistons. I recently built my motor with 9.5:1 CP pistons and CP rods for high boost, corrections through timing will allow you to run more boost safely and make more power

To answer your question, no you can’t increase CR through the head, if anything it’ll lower it more. If you want 10.2:1, get new pistons
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E92 420 E92 420 is offline
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Default 09-18-2020, 11:35 PM

Quote:
Originally Posted by greg_e
You canít add more material to the head to increase compression. CR is mainly done through the pistons. I recently built my motor with 9.5:1 CP pistons and CP rods for high boost, corrections through timing will allow you to run more boost safely and make more power

To answer your question, no you canít increase CR through the head, if anything itíll lower it more. If you want 10.2:1, get new pistons
You wouldnít add material to increase compression you would remove it.

By Fitting a thicker or thinner head gasket will lower or increase compression slightly.


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brendan brendan is offline
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Default 09-19-2020, 10:22 PM

Quote:
Originally Posted by greg_e
You canít add more material to the head to increase compression. CR is mainly done through the pistons. I recently built my motor with 9.5:1 CP pistons and CP rods for high boost, corrections through timing will allow you to run more boost safely and make more power

To answer your question, no you canít increase CR through the head, if anything itíll lower it more. If you want 10.2:1, get new pistons
lol
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E92 420 E92 420 is offline
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Default 09-18-2020, 11:38 PM

Quote:
Originally Posted by KnighTT
So, If I picked up a set of JE pistons with the 9.5:1 compression, you can correct CR back to 10.2:1 when you have your head decked, right?

I just don't want to pay for the CP pistons at $1100+ just because they are set to 10.2:1.

I mean I'm going to get the head worked on anyways.

Pros, cons, remedies?
You could probably do it by removing material from the head and or block yes. However JE make 10.2-1 pistons as well you know.


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