Here's an example..
If you called Bullet cams, gave them some basic engine specs and also how much valve drop you have at TDC, then they can pretty much tell you the limits of what you can install.
What’s the drop at 10-15 degrees before and after TDC because that’s where they are close.
Plus, whatever the drop is won’t be the same when the valve train is installed. They only way to know for sure what you have is to measure it. Anything else is a guess.