I currently have a 2008 27 ZR with the 496HO power. I did add Dana Headers this year as well, but otherwise stock. I am running a 1.65 ration Bravo X now with Bravo 4 blade 28 pitch prop. Also have the Bennett Trim Tabs, which are pretty worthless. Anyway, I'm considering upgrading the power to around 525 (or about 560 with the headers). Probably will go with the Raylar kit as opposed to buying a used Merc 525. I would also upgrade the drive to the Bravo XR (1.50 ratio with 28 pitch Bravo prop), and add Merc K-Planes (280's).
My main question concerns take-off performance. I don't know that there were too many 525 27's from the factory, and I'm not sure if anyone on this site has upgraded their power from the 496HO. I'm wondering, though, if anyone has any thoughts on what I could expect on take-off performance. Right now, with 5 adults and full tank of fuel, getting on plane is pretty tough. Usually have to move people forward, rock the steering wheel back and forth, to get on plane. Putting the Bennett Trim Tabs down does not help with take-off. So, I'm wondering if I added the extra power, as well as the K-Planes, whether I would see better take-off performance. I spoke with Chuch at Donzi, and he doesn't really think I will see much difference, until I get on plane. Then of course, I will see a difference in performance. I guess one question is whether the K-Planes themselves would help with take-off performance, and maybe I start there and see before I spend a chunk of money on more power. I'm pretty sure I'm going to do the K-Planes regardless, because I'd like a little more control at top end, which the Bennett's just don't provide.
I'm able to run 70-72 at top end right now, and I don't really care about running faster (it would be nice, but it's not critical). I'm mainly looking for better take-off performance. But maybe the hull design of this boat, with the single engine, just means that take-off will always be a challenge.
Any comments would be appreciated.