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408 compression help

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Old May 21, 2018 | 10:57 AM
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Default 408 compression help

Hi everyone i am building a 408 out a of a 6.0 iron block and i was wondering what would be the max compression I could get using 93 octane pump gas. And also what side piston to go with ie: -3,-8 flat top,dish.
ENGINE SPECS:
-TSP Rotating assembly(not sure piston cc because thats what I need to know)
- PRC 247 heads
-TSP .660 lift Springs
-TSP stroker cam 242/248 112lsa
- Fast 102 with 102 throttle body
- a4 with 3800 stall
-3.73 rear gears
i guess thats really all that needs to be known to figure it out some people said with a 408 93 octane will be fine some said with aluminium head you shouldnt go above 10.5 some said 11.5 will be Ok and will be good on 93. So the question is will 11.5 be to much for the heads and 93? Or should I get pistins to make it 10.5? If so what cc piston and head gasket thickness?
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Old May 21, 2018 | 11:13 AM
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From: Howell & Fenton MI
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I run 11.5:1 on 93 with my 370 6.0, and I have no issues.
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Old May 21, 2018 | 01:02 PM
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Speak with TSP! They're very knowledgeable and will steer you in the right direction. They might have other suggestions for your build and there rotating assembly as well. They've done enough of these combo's to know what works and what doesn't.

Call them.
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Old May 21, 2018 | 01:52 PM
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Called tsp they said 11.5 is not an issue on 93. As long as the cam is big enough which he said mine is
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Old Jun 19, 2018 | 08:46 PM
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I run 11.1 on 91 with no issues.
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