What would be the better rpm range for my motor, Its a MB 35 with heads, carb and exhaust. With a 38 top and 48 lower it turns 4300 trimmed down(no rooster tail) and 4500 trimmed up with 2 people (200 lbs each) and an icechest. With 38/47 it turns 4150 trimmed down and around 4350 trimmed up with the same load.

I'd stay 38/48 if it was me. Gear it too much & it'll be a dog with a 3rd person or full 2 man hunt load.

dfou, i just finished putting a carb on mine so we will have essentially the same motor. What kind of boat do you have it on? i have a 4300 rev limiter and im sure i will be hitting it unloaded. But as long as im not hitting it with a 3 man hunt load i will be happy

Mine is a 1650 custom. With stock gears I was on the 4600 rev limiter at half throttle