Thanks for the feedback boys. Maybe I have been over trimming out, let me experiment again and I'll report back.

if you were trimming too far out you would have more rpm, or blowing props out making way more rpm...

That combo will rarely hit 70 but should be close (over 65 all the time). You should also spin about 5,000-5,100 rpms. Seems like 28's might be too big for the boat???? Are they 1.5 or 1.65 drives?

I think I may have been trimming out too far, let me take another run on her and share the findings.

i dont think it's your trimming. With my drives all the way in I would still go over 50mph... What RPM were you at? I had a similar issue this summer where the port motor wouldnt want to rev.. I changed fuel filter and was good to go.

Does the boat feel sluggish? Does it sound as if the engine is straining? I would think running WOT and doing 50 the boat just wouldn't feel or sound right. Plus what's it doing out the back? Do you have a lot of spray? Is it calm and flat? Does the boat feel like the bow wants dip into the waves?

I believe they are 1.5's

I'll go along with that. 26 Bravo 1s will wake it up.
Again what RPMs at WOT??

Update.
Took an ocean stroll to Palm Beach tonight. Mid to 3/4 throttle position, trimmed out to 5 max RPM is 4k and 47MPH.
Advance to full WOT and RPM is 4100 max 51MPH max estimated.

The fuel filters on the motors are new, and I've located an red anodized tubular Flow EZY in-line filter on both fuel supply lines made in Ann Arbor MI that I can not verify when they where new/serviced/changed.

Conditions: 1'ers, just myself, full fuel, full water, GPS based speed.

Whatcha boys think, in-line filters the culprit? Bypass them or replace? Are two fuel filters per motor necessary? Had computer on each motor last week to diagnose a needed relay replacement, code cleared and no other codes found.

Start with checking compression and replacing spark plugs, leak down test would even be better...check fuel pressure as well...My guess burnt valves or fouled spark plugs