Home  |  Super Tips  |  BBC Boards

Basic Boat Setup

Probably the most common question we get at the shop and on the bulletin boards we frequent is, "What's the best setup for my boat?"  I would like to tell you that there is a secret formula for success and there is....Hard work + trial and error = 1 dialed in rig.  There are three considerations in selecting your setup.  Engine Offset...engine height...and prop selection.

Engine Offset:
Your engine acts as a lever to lift your bow and reduced wetted surface area on your boat.  The farther back your engine is, the more leverage it is able to exert as it moves farther away from the center of gravity of your boat.  Another feature of offset is that as you move the prop away from the pad you give the turbulent water coming off the pad a chance to recollect.  This feature can result in better prop efficiency as the prop has a better water stream to bite into.  Engine offset is achieved in two ways.  First, a manufacturer can recess the pad (or running surface) from the transom.  You can also install a jackplate on your boat to increase offset.  But before you start bolting jackplate to jackplate there are potential negative trade-offs with additional offset.  As you move an engine farther back you can actually enter dead spots in the water stream coming off the pad.  Yes, on some boats a ten inch plate will not perform as well as an eight.  Also, as you move the engine back you can create some obnoxious handling characteristics.  Excessive bow lift during running and holeshot and downright dangerous turning performance.  For the purpose of discussion we will consider V6 motors on boats 17 to 22 feet.  As a very general rule, most boats use plates from 6" to 12".  Usually longer boats and bigger motors like more offset.  Check your manufacturer's warranty before installing a plate to make sure you are not going to void any portion of your warranty.

Engine Height:
Boat speed is simply the result of prop efficiency and forward thrust versus friction (wetted surface area).  You are constantly trying to get your boat to run on a smaller wetted area and you accomplish this with the leverage your motor and prop can exert.  But there is another component of friction.  That is the gearcase of your motor itself.  Today's new motors have very hydrodynamic gearcases as compared to the motors of say ten years ago.  But if you can raise your motor higher you will reduce the actual amount of gearcase in the water and thereby reduce friction.  But here's the rub.  As you raise the engine you lose leverage.  If you raise the engine too high you lose bow lift and your rig will fall on its nose and run slower.  For any combination or rig, prop, jackplate and load characteristics there is a "sweet spot" or ideal engine height.  But be careful - as you raise your engine - waterflow to your lower unit water cooling pickups is reduced.  I strongly recommend that you  have a water pressure gauge on your boat if you are going to use a jackplate.  Your dealer can tell you what minimum water pressure you must maintain at wide open throttle.  Also keep an eye on your RPM's as they will increase as your motor is raised.  Don't exceed manufacturers' rev specs if you want to maximize the life of your motor.

 Another question is.."will a nosecone or CLE gearcase make my boat faster". The answer is.."it depends.  That style gearcase isn't faster by nature.  But if you could raise your motor higher (except you lose water pressure), the low water pickup will allow you to do so.  The shape of the gearcase isn't for speed, it's to prevent an extremely dangerous condition called blowout.  Most manufacturers' gearcases are subject to blowout at speeds approaching 80 mph. So it's something the average Joe doesn't have to worry about.

Prop Selection:
Here's the one that runs people ragged.  Today there are a number of great high performance props on the market.  But what runs great on your buddy's Bullet might be a dog on your Champion.  Let me state this very clearly.  Each different hull design on the market has its own unique lift characteristics and requirements.  It all comes down to trusting a qualified dealer who had direct knowledge of the hull you are using and what features (speed, rough water handling, etc.,) you value most.  There is only one rule in prop selection.  TRY BEFORE YOU BUY!  You can spend $1500 on three different props and not have the right one.  If you can't find a dealer who will let you run the prop before buying it - keep looking.

The Setup:
If you will check our article on this website on setting up the Yamaha TRP....guess what? It's the same basic procedure for setting up any engine.  A few words of caution.  Don't trust anything besides GPS or radar.  Your speedo is a joke (unless you dropped a couple of C notes in a Gaffrig setup.)  Keep notes on every run that include holeshot, top speed, lift and handling, max RPM's, water pressure at WOT and general impressions.  Somebody asked me the other day if it was a good idea to publish our "secrets".  Well it's not about secrets, it's about hard work.  Those dealers who are not willing to work for their customers won't change no matter how many "secrets" you tell them.

Good Fishing,
Rico Silvera       Nichols Marine