I had a rebuilt '85 Johnson 175 V6 put on my boat. The mechanic used my current fuel lines that are 5/16". He told me I would need to replace the fuel lines with 3/8" lines. The engine is set up for 3/8 lines. <br /><br />1)Would the 3/8" lines make a difference in the performance of the engine?<br /><br />Right now I am turning 5000 rpm at wot and getting about 46 mph with a full tank to half tank of gas and just myself on board. The boat is an 1990 18' Cobia. Weight is about 1300 pounds not including gas. Have a 35 gal. gas tank, not sure how much the gas weighs. I have a 15x21 prop.<br /><br />2)Is this as fast as I should get or should I get more speed? With my old 1990 100hp Merc I got about 38 mph under the same conditions.<br /><br />Any advice is greatly appreciated<br />Thanks,<br />Barry
