View Full Version : Updating mercruiser 57 to vortec

01-07-2006, 12:13 PM
"i have a 97 mercruiser 5.7 l 260 hp that has a leaking head gasket, or cracked head, getting water in 2 cylinders. i am wanting to update to a vortec 350 315 hp... will i see any noticable improvement in performance? ill be going from 260 hp to 315, have been told by others that i wont notice the difference. its in a rinker fiesta vee 266 cruiser
thanks hud"

01-07-2006, 09:43 PM
"No. I had one in a Bayliner 28 foter, and it was no faster than the old 260 Volvo. Other than in a race boat, torque moves the boat, and a Vortek hasn't that much more. Hp, yes, torque, no.


Harves Marine
01-07-2006, 11:37 PM
That water is most likely coming from an exhaust manifold or elbow.

01-08-2006, 12:38 PM
"Is there a way to "order" the vortec motor with more torque? in other words ,,, for a heavy boat, is there a configuration on this motor that will produce more torque? i am considerint the AFFORDABLE FUEL INJECTION system,,, ill check with them and see if they can tune a injector system to make more torque... thanks you guys... hud"

Harves Marine
01-08-2006, 03:57 PM
"If you are to order a motor get a 383 stroked small block, natural torque from the cubic inches, torque from the improved rod angles. Then put your Vortec stuff on top."

01-08-2006, 06:52 PM
will this hurt the realiability of the engine? will i need to change the cam?

Harves Marine
01-09-2006, 07:30 PM
"No issues of reliability, ? change the cam, of course you would like to spec a cam or buy the engine without a cam and install it yourself. I could recommend a couple of grinds for I just did this on a twin application although they were 350's. Build for torque and the horsepower will come along with it."

03-18-2006, 01:26 PM
is the lower unit casings of a bravo 1 and 2 the same as a bravo 3?

03-18-2006, 01:34 PM
"No, 1 and 2 aren't even the same.

P.S. you will have better results if you start a new string when you change the subject."

03-18-2006, 05:54 PM
Sorry Rick....took me a minute to figure out how to post.