FORUM RULES UPDATED - The forum rules have been updated to continue to provide a friendly and safe environment for our member community. Please take a moment to review the updated rules and our terms of use and privacy policy. Click here for Forum Rules which has links to the 'terms of use' and 'privacy policy'.
I have a 96 75 horse merc--I notice the 75 and 90 are identicle in weight and displacement--the max rpm for 75 is 5250 and max for 90 is 5500--is the only difference in these motors caburator jetting
The reason the RPM's are different is the powerband the 75 runs better at 5250. There is a little more difference than just carb's. The port timing is the main difference
