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How much boost on 91 octane

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How much boost on 91 octane

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Old 01-11-2025 | 04:44 PM
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Default How much boost on 91 octane

My engines are rebuilt 525efi with rods, pistons, stock compression, Cometic gaskets with studs, Teague stage 3 camshafts with whipples and MOAC intercoolers. I am running at 6000ft elevation and have pullied to 7psi but I am looking to add some more boost and am only seeing 5400rpm. Whipple has told me to just pulley it down to get 11-12psi, just looking for some opinions.
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Old 01-12-2025 | 10:23 PM
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I'd say you are already maxed out for 91 octane at 7psi.
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Old 01-13-2025 | 09:11 AM
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I'm pushing about 800HP with a 3.3 whipple and cometic gaskets, aluminum heads, stock compression. I run 92 octane and 9psi at 5,500rpm. I have looked inside and don't see any evidence of detonation so far. I'm at sea level. I'm not going to push it any further though. Hope that helps.
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Old 01-13-2025 | 02:33 PM
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11-12psi you`ll be collecting parts out of the bilge.
I wouldn`t go more than 7 psi.
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Old 01-13-2025 | 02:40 PM
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Whipple wont be sending you any money when your engine blows @ 11 lbs of boost
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Old 02-06-2025 | 02:28 PM
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Ill be upping the octane to 95 and turning my fuel psi up a bit.
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Old 02-06-2025 | 03:58 PM
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What ECM are you running
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Old 02-06-2025 | 04:00 PM
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MEFI 4. I would like to go Holley eventually since the 555 pcms were deleted.
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Old 02-06-2025 | 04:03 PM
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Where is the limiter set ? stock 555 controller on a 525 is 5350
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Old 02-06-2025 | 04:07 PM
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6000rpm, my Whipple setup is older, the 555 was deleted and an MSD ignition and MEFI4 was installed.
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