840 or 808

Redeye2 said:

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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The HO button only ENABLES the 840 HP tune. It's up to YOU to make sure the octane is sufficient. If you enable the 840 tune and then you only have 93 octane in the car, nothing will happen if you drive normal or close to normal. Once you go full throttle the car will experience knock and then the car will drop out of the 840 tune and it will tell you in the DIC. And, yes the engine will no longer be Blue in the Display. You will have to cycle the ignition to be able to enable the 840 tune again. It states in the Owners Manual that this can damage the Engine but I know of some that have tried all kinds of stuff and tested repeatedly to see if it would stay in the 840 mode. So this is very conservative and engine damage must be rare. But still........