Hi,
I would like to know the max elevation difference that anyone has tried without a hard adjustment, other than just adjusting idle mix or jets other external adjustments. I have two Holly 850s on twin 1998 Merc 542 Bulldogs, I am going lake to lake and my elevation diff is about 1200 feet. She runs a little rich at 1900' vs 685' Elv. Other than the engines loading up a little and maybe fouling plugs which has not been an issue yet, I don't have a problem with cleaning it out once in a while when going in and out of the Harbor. will this eventually harm the motor if continued. I am going to call merc also I just wanted to see if anyone had any info.

Thanks, Happy weekend.