What is a turbo prop?

[John Bett]

What is a turbo propeller? Is it the same as a cupped propeller and why does a turbo prop allow for higher top speed?<br />Thanks

 

[angus63]

Re: What is a turbo prop?

Are you referring to an exposed propeller (Turbo brand) or an encased (shrouded) assembly around a prop like the military outboards have? Turbo is a brand name for an exposed prop, and also a description for a shrouded assembly around a prop. These are used on vessels doing rescue/recovery work for safety, as well as use in weedy shallow water.<br />BTW Also a term given to turbine driven propeller motors on aircraft!!!

 

[Dhadley]

Re: What is a turbo prop?

The Turbo prop is designed as a performance prop and can run at a relatively high X dimension. That equates to better overall efficiency and top speed. The Turbos cost more than something like a Stiletto but youre paying for the technology.

 

[John Bett]

Re: What is a turbo prop?

Is the top speed achieved by a turbo 'brand' prop enough to constitute the cost? For example, If I could reach a top speed at 5500 rpms with an old evinrude V4 with a 13 3/8x17, and I switched to the same in 'turbo style', what speed difference do you think I might get? Thanks

 

[Dhadley]

Re: What is a turbo prop?

The difference in speed would depend on what brand prop you have now and its condition. If you had, for example a 17" SSTII thats in good shape and youre getting 5500 rpm I wouldnt be surprised if the r's dropped a couple hundred with a 3 blade Turbo. Then we'd work with the set up to gain the rpm back and look for 5800 so youre not lugging it. <br /><br />If your current set up does not include a jackplate, you might think about one if youre going to use a Turbo. If a jackplate is definately not in the plans then a Stiletto may work better. Dont pay for technology you dont plan to use.<br /><br />How much speed you gain has a lot to do with hull design. On an Allison or Hydrostream I'd bet 5 mph isn't out of the question at all. Another design like a Mako we're looking at maybe 3 or so. It really depends on how much hook the hull has. And as mentioned, hull design.

 

[John Bett]

Re: What is a turbo prop?

Thank you, Dhadley for your advice. I dont have a jack plate, but I have a CMC tilt/trim and have the motor set at top notch. The boat is a 1970 KNOA fiberglass 18'. Most of them seemed to be made for inboard jet setups, but mine was made for an outboard motor. It is a low profile, but kind of heavy. Is 5800 Ok? The ID tag says the rpm range is 4500-5500. Thanks, John

 

[Dhadley]

Re: What is a turbo prop?

4500-5500 is the range that the motor is rated at. If we're still talking about the 72 125, yes 5800 is OK.