Mine are YellaTerra units.
I am yet to fire the engine but it should all happen very soon. The tailshaft is in. I await the gaskets from JTS then I'll bolt the manifolds on and start it up.(hopefully)

Ratios available from yella are 1.55 or 1.65:1 You can option them in mixed sets if you want different inlet and exhaust ratios.
Mine are 1.65:1.
I'm using a small cam in this engine to start with till I get a handle on the car.........then I'll be changing to a bigger one when I do the engine freshen up and piston change.

I'll let you know how well it revs once its run it.