Ventura needs more Speed


This website is invaluable to me, as the owner of a 1983 Ventura II.  The Tech column has no equal and your knowledge is above reproach. 

I took my Ventura II out this morning on Lake Washington at 6am.  Perfect running conditions, light 5 mph south wind and just a light ripple.  I finally changed my prop (I got the spacer).   

I ran 58 mph at 5800 rpm (stock 1983 140hp Evinrude) with a 13 x 23 prop (heavy alum. prop unknown brand).  My motor is mounted in the uppermost hole of the motor bracket, propshaft is 2.5 inches below hull centerline pad.  There is no setback/jackplate. Should I be measuring to the centerline at the rearmost part of hull at the transom or at the stepped pad forward of the transom, where the bilge plug is? 

While trimmed just slightly before chinewalk, I saw 58mph with a 4 foot high roostertail. (I just installed a new Teleflex speedo and pickup).  I was running into the breeze.  I love the sound of the Evinrude trimmed up at high speed... 

Friday I will take it out again, with the 2 -  6 gallon tanks removed, leaving just one 6 gal tank and saving 90 pounds or so.  I will take the bench seat out also (needs to be rebuilt anyway).  I think I am running at about 1350 lbs total gross weight (driver and all).  Is there a way to reach out and touch above 60 mph without having to buy another prop? 

Lastly, any advice on how I tell my wife this is still the family boat that she wanted?  I am sure I will be sleeping in the Ventura by the end of the weekend... 

Best Regards,



Sounds like a nice ride. To measure the height, use the bottom of the pad (by the drain plug). You could have some cup added to the aluminum prop by a local prop shop. Cost should be about $30.00. That should help lower the roostertail and get you over the edge. 


P.S. Tell her how good she looks while in the boat - might work.



Please submit whatever questions you have to  All questions and answers selected will be displayed on this page as they come in.  Note: though all boaters are welcome, priority may be given to I.H.R. members.  Randy can not be held responsible for any advice given.  Though his information and expertise is second to none, he has no control over what you do with your boat.  It is up to you to boat safely and act responsibly, and his advice is only to be used as a guidance for your high performance boat/motor of which you are the one responsible for the risks involved.

Mark C.


[ Home l About I.H.R. l History l Models l Registry l Members' Pictures l Feature Article l Tech Talk ]
[ Literature l Events l Top Guns l Guest Boat l Classifieds l Video Gallery l Racing Corner ]
[ Prop Slippage Program l Animated Videos l Screen Savers l HIN Decoder l Links l Contact Mark ]