What performance upgrade is recommended for a 92 model Merc 75? It's on a Sea Ray 160 LTD that looks really fast but only tops out at about 40 MPH. Prop is standard. Any ideas?
40MPH is fairly good for your setup,K.<br />But you can improve planing time by adding a stabilzer (like a doelfin) to the cav plate.<br />See a merc dealer about borrowing or renting a higher pitched prop. But if you change the prop pitch, keep an eye on the RPMs to make sure you are getting full RPM with the increase in pitch. If not, you are over-propped, and must revert to the original.
Hi K!<br /><br />I'm runnig a 160 CB - born with a Merc 115 4-cyl 2-stroke. It came with a 19" alu prop and due to the somewhat special design of the transom (so to speak fits the engine an inch above recommended ideal), it caught air and cavitated heavily under accelleration. Went up in rpm, making a lot of foam behind the boat without going nowhere. Lost grip at even wide turns or the smallest trim out. Switched to a Quicksilver High Five 23" and got it all: Never looses grip (as enough blade area is in the water at all times), allows for any amount of trimming, accellerates fair, makes 50+ mph and has great cruising economy/noise level. At top speed trimming makes it feel as if the hull gets airborn.. <br />This is the largest 4-cyl from Merc which helps very much in keeping runnig costs low (especially here when one liter of gas costs a dollar...)<br /><br />Of the six boats I've owned, the Sea Ray is by far the best.
I have a 16' Glastron GS160, the motor is a 1979 Mercury 140 inline 6. The 140 is at the crank, at the prop I have about 126 or so. I get great mileage and enough speed to almost start chime walking. I am running a 13 x 17/19 (One of the two). At WOT I am at 5800-6000 at sea level and at 2370' WOT is 5500 - 5700. I can pull up to three adults on single skis at a time though I only did that once to see if I could. I can easy get 4+ hours from a 16gal tank. When I got the motor, he gave me a 21 or 23 pitch prop and although it was exilerating at 65 - 70 mph. That was way too fast for that size boat. The prop I have now is the smallest I can use and am able to keep the speed down to a managable level for other drivers cause I must ski also.<br /><br />HAve a great boating season everyone and hope to see some of you on the water.<br /><br />Craig
<br />This is the largest 4-cyl from Merc which helps very much in keeping runnig costs low (especially here when one liter of gas costs a dollar...)<br /><br />Of the six boats I've owned, the Sea Ray is by far the best.
