Here's my version of the manual. Mine is for a 2002 model. Very interesting that there's a difference! Dustin appears to have our real-world answer.

Dustin,

I have to use the gas available where I boat, which is typically 89 octane, and occasionally (rarely) 87. As I understand your upgrade options, to get a substantial power increase I'd have to run 91 octane based on your ECU recalibration.

What's your recommendation for a person like me?

yeah.. i don't understand why they are different either but mine is on page 53 and my book is a 2003

Don

If you have to run lower octane, then you can do the same work but with less total spark advance which will lower the overall power output. To get some back, we can install Az's intake and then we would recalibrate the factory ECU for those changes. Or you can lower the compression, do all the upgrades, and then supercharge it and make around 650hp on 87 octane. It will make just under 750 with 91 octane.

Were not going to produce the engine covers and were using stock exhaust.

Thanks,
Dustin

Dustin,
are you changing the exhaust and putting tail pipes in place .. i thought the cam overlap was to big to run stock exhaust.

Thanks,
Don

Dustin, Have you had chance to test and come up with a recalibted ECM for the new 525EFI? I have one with low hours but it seems run very rich. Wondering if you could help it out. Thanks.