What you can try:
less mast rake (if you can, 1.0 degree is pretty close to where it’ll sit naturally) if you’ve got a shim in on top of the mast, remove it.

bump the mast base (sail) back in the track. Thats possibly what the problem actually is given what you’ve said. The tuning can be finite once you start to dial it in, but for now , move it a decent amount, say 1cm + it should make lift off and staying up much easier. Moving it forward will help to keep the lift the foil gives you in check. Too far forward and the rig weight and down force from the sail will hold the board down.

also try the age old tip of…. More downhaul. Too tight a leech at the top of the sail will also counter your pumping efforts, and hold the nose down on certain points of sail.

is there weed where you sail? What you’ve described is what it feels like when you catch some.

its a bit counter intuative, but bigger boards are actually harder to pop onto the foil than smaller ones. Its what they can do once on the foil that they come into their own.

edit: some of the above might sound simplistic/stuff you’ve already encountered if you’ve been foiling for a while, but the importance of it all amplifies when you’re on a bigger board/higher aspect foil than freeride.

Thanks guys!
No weeds where I sail but it sure felt like it.
After some research, my board's mast track is 5cm further forward than the iq board.
Here's what ai said:
"The Reality of the 5 cm Shift
A difference of 5 cm (2 inches)[/b] might seem small on paper, but in hydrofoiling physics, it radically alters how the board balances on the water:
On your Foil 177:[/b] Because the mast track sits 5 cm further forward, placing your mast base in the "middle" of your track pushes your sail’s downward pressure significantly further ahead of the foil's lift center. This is exactly why the board feels incredibly sticky[/b] in 10–12 knots; the rig is physically pinning the long nose down. When you finally break that suction by pumping hard, the board suddenly pivots on a longer lever arm, causing that aggressive pop-and-stall behavior."
Seems to be exactly what I am experiencing so I've jimmy rigged the mast foot back to 104cm so hopefully that will help (I was using a 2 bolt plate so I didn't have much adjustment but I found a single offset mast foot).
I've got wind monday and tuesday so I'll give it another go!

Joe

Success!!
Went out in some decent wind with the base back and had the same problems - hard to get on foil and sudden drops.

Took off the straps and it clicked.

Rode for a couple of hours strapless - perfect.

Look like my feet are about 2" forward of the strap inserts - probably why I would stall out the foil on takeoff.

Anyway I will ride strapless - not a big deal as I ride my wave foil setup strapless and prefer it.

Thanks for all the tips!

Joe