I have a 1986 2600 Continental with a 260 Mercruiser engine 5.7 the boat takes forever to get on plane and is using way too much fuel can someone tell me the recommended prop size I know how to use the trim tabs I know how to use the outdrive trim I'm not happy with the fuel consumption
I'm not sure of the recommended prop size. I'd recommend calling Tiara customer service. However, I did a search on The Hull Truth and I think what your experiencing is common for that boat with a single screw.
What is your RPM @ WOT. Should be 4200-4600 with boat trimmed out. Less than 4200 RPM & your are over propped. More than 4600 RPM and you are under propped. I own the same boat & fuel consumption on a smooth lake is 2 MPG. In rough water with hull pushed down (tabs down & prop all the way down) to keep the bow from slamming, you will get less than 1.5 MPG. Its a heavy hull & under powered with the single 260 HP engine.