How to Choose a Boat Prop
January offers a good time to think about propping your boat for the coming season. Having a good prop on your boat can make a huge difference in performance, no matter what kind of boating you are doing. There is no perfect prop that will work wonders for every condition. Although we all want a prop that will give us the highest speed, great hole shot and perfect control, you have to give or take a little. Fact of the matter is that you will want to prop your boat with one that most closely matches the conditions you are in. You may even want to have two different props to get the most out of your boat. So here are the steps to ensure the best performance out of your prop:
1. Properly identify the recommended prop for your specific engine. The best (and most of the time, only) way to do this is to contact the manufacturer of your engine directly. The manufacturer will give you the best application for your current conditions and motor size. They can also tell you the optimal RPM range for your engine running at WOT (wide open throttle). Or, you can take the measurements off of the prop you have been using. You can find the prop specifications etched either on the outside or inner hub area of the prop itself. The specs should read something similar to the following:
14.25x19R
diameter pitch right hand rotation
2. Next, decide what kind of performance your are looking for. You should keep in mind that there are a lot of things that effect overall performance. To get the desired effect you should test with the load you will be using on a regular basis. Things will change once you load the boat with a full load of fuel, equipment and a fishing partner. The easiest way to change performance is through changing your pitch. If you raise your pitch, you should see an increase in top-end speed. If you lower your pitch, you will get more hole shot (gets out of the water faster). So for skiing, you probably will be concerned with more hole shot, etc" But also be aware that a change in pitch will also change your engines RPM's. As a general rule, an increase in 1 pitch decreases RPM's by about 200, and vice-verse. Most people try to stay with the same diameter, or within about " inch.
3. Next, decide on aluminum vs. stainless steel props. Stainless steel props claim better performance and obviously last longer. However, aluminum props are cheaper to buy and replace. Other factors need to be considered as well. Identify all of the conditions involved in your "regular" boating. Are you in shallow water, deep water, salt water or fresh water If you are in shallow water and your prop has more of a chance in getting "dinged", then maybe an aluminum prop with exchangeable hubs and housing is your best bet. In this manner can you better protect your shaft from being damaged if you do hit something (stainless steel are more durable and therefore can transfer impact up through your shaft, causing engine damage). But most skinny-water boaters opt for a stainless-steel model. Stainless steel would be best for saltwater applications and deep water cruising for optimal performance.
Many boaters actually carry two different props on their boat, to enable themselves to run in any condition. Since changing out props is a fairly simple task, having two props offers a great solution to the many options out there.
As always, iboats.com offers the best selection of props for any boating application. The iboats.com prop finder is easy to use and offers many different options for just about any boat and engine out there.