Rebuilt 1997 Mariner Magnum 200 efi won’t reach old WOT

[RMCR640]

My cobra viper 201 would run mid 60s before rebuild. The WOT now is about 52 mph. Plane out good and so it mid range power, but top has stopped at 52 even after break in. I have noticed the pressing the trim button while running at WOT would give a small bust of power recently so I checked all batter leads and made sure they were tight suspecting a bad ground but got the the same WOT. Just curious what next I should check next?

[EuropeanAM]

Welcome to BBC!

Have you verified that the throttle plates are horizontal in their bores at WOT? That stop screw on the front-half of the crankcase is often overlooked as a critical set when performing the Sync-n-Link procedure.

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