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840 or 808

2350 Views 7 Replies 6 Participants Last post by  2048 Demon
Had my dealer install the crate PCM and high octane button. When I put 100 octane in or 93 octane in, it shows up in blue light that 840 high octane activated. Why would it show that with only 93 octane?
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.... and once the ECU detects it, the damage could be done :(
Knock sensors , exhaust gas temperatures, and O2 sensors protect the engine from operating with detonation. You will need about 8 gallons of MS109 race fuel to 2 gallons of 93 octane unleaded to keep the knock sensors from kicking you out of the high octane mode on the Demon. This has been my experience with my Demon.
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