My crownline has a 5.7 efi. Recently ran into a guy while boating that had an eliminator with twin 1100hp engines that he built. He told me that i could prop my engine to 5000 rpms without issue or damage. Merc says 4800, would like your collective opinions.
thanks

FYI, Brett his name was Stevie and he said he knows you and has dealt with you many times.

My opinion 200 rpm more and the GM will remain happy! done in my 350MAG for years I owned it without any failures.

A 260hp 350EFI is all out of cam at 4800. Spinning it to 5000 won't give you more speed since your hp drops off.
If top speed is your goal, go to something like a 21 pitch Mirage. The Mirage has good bow lift,, and will keep your bow high without hsving to overtrim.
Looking into a prop that has had the blades thinned will also yield better performance at the expense of suffering much greater damage if you hit anything (log, etc).
There is no free lunch.
A 21p 3 blade Mirage, with thinned blades may give you 2mph or so.

But there are other non-prop ways to get more speed. In a straight vee with no lift pad, your goal is to:
#1- Get any unnecessary weight out of the boat. Don't run a full fuel load, leave the porta potty at home.
#2- Move all weight as far to the rear as possible.. Store NOTHING under the front seats.
#3- If your boat has trim tabs, make sure they are full "up" (tabs up = bow up).
#4- Learn best drive trim angle by going up until GPS speed drops. If you don't have a handheld Garmin, etc, then load an app on your phone like Ulysse Speedometer.
Keep your boat's bottom clean.

Don't make the mistake of pouring lots of money into "performance goodies" for your boat. Your hull will be relatively happy into the mid 50's but above that, each mph costs more $ and your boat won't be within its design envelope.

When your boat no longer satisfies your speed lust, sell it and buy one that has a hull intended to, and equipped to perform at your desired speeds.

Your "water" will also steer your decision. If typical weekend traffic results in you getting beaten half to death in 22 footer, you may need to be looking at a longer deep vee, or a tunnel style boat.

But, for now, enjoy tweaking your setup to maximize what you've got.