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I don't have a PA but I do have a TI, we have pretty massive sails and twin big outboards on ours. Without the mirage plug in the mirage drive openings throw up a lot of water. At around ten mph the rear seat area fills with water, at 15 mph it's a massive flood on the rear passenger, and at 20 mph it's pretty much a 4 inch fire hose at their face. With the mirage drives in and bungied against the hull, the mirage fins flutter quite a bit at anything over 12 mph (likely causing damage), however if you keep pedaling they hold up just fine even at 15 mph, however over that the pedals become very difficult to pedal so it's best to remove all the mirage drives and put the plugs in (you can't go fast without the plugs in). However I don't think the boat is designed to withstand those loads especially in rough 2-3 ft offshore chop. The entire boat flexes and bends more than you can possibly imagine and the ride is really rough and wet (imagine a 20ft powerboat running thru rough chop at 40 mph (the TI is way worse at 20, (bone jarring)) and way wetter. My absolute max speed is 20 mph with sails and motors running, anything over that speed with the props in the water the motors over rev and explode (I have exploded several now).
Another problem is unless you convert the hull to a planing hull, the pointed stern of the boat goes completely underwater at around 12 mph creating massive drag, so in my estimation a stock TI hull is good to around 12 mph before horsepower requirements start going up exponentially. Obviously giant sails create horsepower, I figured it out once that in order to get the boat up to 20 mph my sails had to generate close to 45 horsepower, that's a lot of strain on everything that the boat is not designed for. My twin 2.5 hp outboards with no sails easily propel the boat up to 12 mph at WOT ( I have custom made high performance propellers). At that speed you have to overcome the displacement with raw horsepower, bottom line if you want to go faster get a different boat...
Just a guess off the top of my head is the PA 17 with twin 2.3 hp Hondas will do about 6-7 mph with the stock props, and around 10 mph with modified high pitch custom props. With a single Honda 2.3 it will top out a round 5-6 mph (higher pitch props wouldn't be an option with a single (not enough horsepower)). A waste of time adding the second motor because on a small lightweight boat max speed is determined by the prop pitch and rpm.
Same applies with Torqeedos 1003's, one should get you to max RPM and speed, adding a second won't propel such a small boat any faster. However if you planning to use the 1 hp evolves, thats a different story, an evolve will propel a revo 13 just fine to max rpm (I'm guessing around 5 mph). A big ole PA 17 1 hp is probably not enough to propel the boat up to 5 mph, however twin evolves probably would.
Actually the power consumption math is very easy, at WOT with one evolve lets assume on a PA 17 you get 15 minutes of run time at 3.5mph. Adding a second evolve (with it's own battery) still gives you 15 minutes of WOT run time, however instead of 3.5 mph the boat now travels 6 mph, you get to go further, not quite double the distance but close (keep in mind you are now drawing from two batteries instead of one (double the power consumption), you can't escape the math. This was only an example, I have no idea what the actual power consumption and speed of an evolve on a PA would be, but the math is the same.
Hope this helps
FE
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