This was a upgrade conversion that was done by Shipyard Marine near Green Bay on the boat in 2001. I have ran it since with great relability.
This upgrade is astounding. It totally changes the personality of the boat. Does it cruise great? You Bet. Is it reliable? Yes. How does it handle the power? Not a problem! Look below and you would swear it is factory.
Shipyard pulled the original 7.4 MPI with 310 HP (620 HP total) and I sold them on Ebay. I bought a pair of 502 MPI's that were pulled from a new go fast boat that put in larger higher HP motors.
This bumped the horsepower on the 31PC from 620 to 830 HP. 1/3 More power or 210 more HP.
Shipyard also installed Corsa Quick and Quiet Plus Thru Hulls which allows you to cruise sounding like a go-fast boat, or as quiet as a normal PC.
I had the Bravo III props tweaked and lab finished by Pro-Peller near Elkhorn WI. Bravo III props leave much to be desired and this guy work some real magic on them. We did my Brother's dual props off his 33' Sea Ray Sundancer and he picked up about 6-8 MPH.
Ok, yada, yada. What about performance?
1/2 throttle cruise at 3,800-3,900 RPM yields 43-44 MPH GPS.
Full Throttle with 4 on board, nearly full fuel and water show 58-60 MPH.
Empty the front water tank and it has hit 62 MPH on the GPS.
Bad habits at that speed? None.
How is this setup on Fuel? No worse or better than the stock setup. Like any boat, just depends how you run it. The props made the boat more efficient, the motors make more torque. You are running lower RPM to get the same speed as the old 7.4 MPI. I have a twin engine FloScan hooked to my GPS.
With Full fuel and water, 3 on board, 43-44 MPH 1.1-1.2 MPG. Slow to 38 MPH and it is 1.3 MPG, slow to 34 and if you trim it right it will get to about 1.4 MPG.
What is the worse thing about this boat? As much as I hate to say it I am thinking about selling it. Why? Because all my **@! friends are getting new Formulas and the peer pressure is killing me.
My challenge is, How do I top a 830 HP, 60 MPH, 31 PC that runs great and still looks like new? I would buy a 370 SS or 400 SS but for our Cruising use that cabin V-berth setup is not what we are looking for.
Anyway. Hopefully I can find the right,,, Formula.....
This upgrade is astounding. It totally changes the personality of the boat. Does it cruise great? You Bet. Is it reliable? Yes. How does it handle the power? Not a problem! Look below and you would swear it is factory.
Shipyard pulled the original 7.4 MPI with 310 HP (620 HP total) and I sold them on Ebay. I bought a pair of 502 MPI's that were pulled from a new go fast boat that put in larger higher HP motors.
This bumped the horsepower on the 31PC from 620 to 830 HP. 1/3 More power or 210 more HP.
Shipyard also installed Corsa Quick and Quiet Plus Thru Hulls which allows you to cruise sounding like a go-fast boat, or as quiet as a normal PC.
I had the Bravo III props tweaked and lab finished by Pro-Peller near Elkhorn WI. Bravo III props leave much to be desired and this guy work some real magic on them. We did my Brother's dual props off his 33' Sea Ray Sundancer and he picked up about 6-8 MPH.
Ok, yada, yada. What about performance?
1/2 throttle cruise at 3,800-3,900 RPM yields 43-44 MPH GPS.
Full Throttle with 4 on board, nearly full fuel and water show 58-60 MPH.
Empty the front water tank and it has hit 62 MPH on the GPS.
Bad habits at that speed? None.
How is this setup on Fuel? No worse or better than the stock setup. Like any boat, just depends how you run it. The props made the boat more efficient, the motors make more torque. You are running lower RPM to get the same speed as the old 7.4 MPI. I have a twin engine FloScan hooked to my GPS.
With Full fuel and water, 3 on board, 43-44 MPH 1.1-1.2 MPG. Slow to 38 MPH and it is 1.3 MPG, slow to 34 and if you trim it right it will get to about 1.4 MPG.
What is the worse thing about this boat? As much as I hate to say it I am thinking about selling it. Why? Because all my **@! friends are getting new Formulas and the peer pressure is killing me.
My challenge is, How do I top a 830 HP, 60 MPH, 31 PC that runs great and still looks like new? I would buy a 370 SS or 400 SS but for our Cruising use that cabin V-berth setup is not what we are looking for.
Anyway. Hopefully I can find the right,,, Formula.....