The 25 P5X will turn about 50-100 RPM less than a 26 Bravo 1 prop. I ran those 2 props on my 28 Heat when it had a naturally aspirated 540. I could spin them to 5600 RPM around 75 MPH. The P5X ran great and really reduced prop slip. This was before I added a drive spacer.

Bent, your peak HP is at 5200 RPM. However, you are only down about 10 HP at 4950. I think labbing the 26 and then adding a slight amount of cup would do the trick. You must have the cup or you'll lose a lot of speed.

Steve,
I will have to verify the x-dimension. The only checking I have done is to measure from the bottom of the transom up to the outdrive. Mine is around 1 to 1 1/2 inches lower than the other 2 Heats in the area.
The power tech 5 blade looks similar to a B1 with the exception of more cup on the end of the blades. I have attached a picture of one. Since there is minimal slip, the power tech 5 blade is really sluggish out of the hole.
I plan to make it to the Jamboree.
Bill

I have a labbed 26 p5x on my 28 heat with a 500 efi. 1" spacer it runs 73.4 at 5100 to 5150. I will never go back to a 4 blade.

Bill,
That looks like a 5 blade Bravo one, not bad. It is definitely a bow lifter type prop.
I would have it blueprinted to your boat, and I am sure you'll be happy with it. Nice find.
Regards,
Steve