How do you think a sation 45 would haul a f*40 around? or shouuld i go larger.

That plane would fly on that size Saito but it would be very borderline for power. If you make a mistake then you will have no reserve power at all to get out of it, but I do not seem to remember Saito making a 45 size engine, I know they make a 40 and it definitely would not be enough. I used to have that plane and on a 46AX by OS it was a perfect match, then I went to the Saito 56 and again a perfect match, just used less fuel

The Fourstar series planes are very forgiving but need some power to really fly well, read that as do what they really can do

i had a four star with a saito 65 and it flew great unlimited vertical it would do anything you wanted.

I would say the 56 at a minimum - 65, 72 or even 82 would be better suited for it.

To answer the 2nd post - I think the 45 was only distributed in europe according to www.saito-engines.info