I’m looking at buy a 2005 27 Concept with a single 225 Opti. If the deal goes through I want to put a 300 XS. Anyone know what kind of numbers it would run, or any suggestions on what motor to use?

I can tell you the change from a 225 opti to a 300 pro xs isn’t going to be a huge performance change.

Doesn't like weight at the transom, so even twin 300XS is out of the question if good handling at top speed is a priority. Great looking ol' school design i.m.h.o.

300XS ~ 60 mph

400R ~ 65 mph

With the 300 XS you'll be in the low 60's - I believe this is true even with the new hull design. I have a 27 with a 300 Suzuki on her - gave up chasing speed and use it for what it is - a great handling, do pretty much anything boat. The best I have seen in 60 +/-. Consistently runs 55+ with 4 people, etc. The Suzuki is by no means a performance motor but its pretty darn economical. Fun boat - we've had ours for 8+ years and every time I think about selling her, we have a great day out on the water and decide not to keep her instead.

Good to know. The seller says 52mph light load with the 225 opti.

sounds about right. When we got ours she had a 250 and ran 55 +/-.