Dug out the engine build sheet from the W9 build 2 years ago and I have conflicting notes on the chamber CC's with the Titanium valves.
What is the average W9 chamber volume with Titanium valves?
Pic from the build

When in doubt, check it out, now
Why not make sure exactly how all eight chambers hold now before you wish you did later

I already wish I did.
That picture was from 2 years ago. I just put it in for reference. The engine has been together for a year.

My street W9s are 55cc with 2.18/1.60 stainless valves. I havent checked my other pair with 2.20/1.60 Ti valves yet, but I would expect 53cc.

Uncut decks with Brett Miller chamber/porting

Respectfully, what's the difference? What were your conflicting numbers anyway? Are they so different they'll change the fuel you'll use? Do a compression test/cylinder press. These in the pic are nearly max milled based on the valves in relation to the deck.

The engine has 200lbs cranking compression with a 275* @.050 cam. We are heading to the dyno next week with VP C12 fuel.

I would take some C10 and several different heat ranges of sark plugs and test, test, tests and watch the results
Good luck either way