Just rebuilt the drive with XRs and put the 1.5s back in it. I'll do a seach and see what I can find. Thank you!

A 27' with a 540 should easily run 80. Stepped or non-stepped hull? Didn't they run 69 mph wit a stock 370HP?
I know the 27' that I have driven was dialed in pretty good, but it is a fast hull.

That's what I'm thinking and was anticipating. I'm trying to see what improvements I can make before I go back to the shop and start pointing fingers, only to look like a fool

It does have a stepped hull. Yeah, I recall seeing old sea trials sheets people posted and they were typically running 70mph or so.

Seems like something is missing, just trying to figure it out. Motor runs healthy, plugs look good, timing is a little off IMO, but high if anything which shouldn't hurt performance (maybe the engine). I'm scratching my head.

Do you still have the collars that the factory installed on the trim tabs? These limit the "up" travel and some chine walk. Removing them - as long as you can drive through the chine walk - is generally good for about 2 MPH.

They were removed from the boat at some point. A touch above 3 on my indicator is neutral and you can definitely feel the boat get loose at high speed once they're out of the water.

You mentioned torque #s but not hp ? what did it pull on the dyno

@ 4000 630tq / 480hp
@4500 635tq / 544hp
@5000 601tq / 573hp
@5500 582tq / 610hp
@5800 557tq / 616hp

Dyno only ran up to 5800

You said your a car guy...with that much slip, your just spinning your tires. No matter what you do to the engine, you arent going to see any appreciable gains in top speed untill you figure out how to get the tire spin under control. you can add al the horsepower and torque in the world and it will matter not.

So the million dollar question I suppose, what’s causing the slip?

I tried a labbed 29 and couldn’t get the boat on plane. Could try it again with better trim and tab settings to see. It was the first time I took it out with the new motor and thought I was having fuel issues so that’s the only time I tried it.

I’m guessing it all comes down to prop?

So many times the prop is messed up.

First thing I would do is try a good known 26 Hydro or maybe Bravo that has not been messed with.