BlackJack/250 SHO High Performance Prop?
 

I'm currently running a BlackJack with a 250 SHO. It is turning a 21 pitch saltwater series 2 prop. I'm seeing 40 mph at 4000 rpm cruising with any load and I'm getting around 63 mph WOT running regular octane gasoline and a light load (1 person, fishing gear, and 1/4 tank of fuel). I'm satisfied with the performance im getting but I've been reading forums about guys running the same boat/motor at 65-68 mph. I'm calling BS but maybe they know something I don't? I know the new 300 Offshore Yammy (same power block as the SHO) is running right around 70 mph on this rig so 68 with a 250 SHO seems a little far fetched to me. I assume they had to be running premium fuel, which I have noticed will run slightly faster in my rig, and with only a couple gallons in the tank. I've been told that running a Bravo 1 XS prop instead of the saltwater series 2 may increase performance but I am no expert when it comes to props. The SHO runs great on my BJ with the saltwater series 2 but if these guys aren't full of crap about their performance numbers, I'd be extatic to squeeze a few more mph out of my rig. If there are any prop gurus lurking or if anyone here has experience with the SHO and different props, I'd appreciate your insight as I don't have much experience playing with props. All I'm looking to do is maximize the performance and efficiency of my rig if there is a better prop out there than the one I already have.

And if it matters at all, I forgot to mention that even at 1/2 to 3/4 tank of fuel, still running 62-63 with 1 person in the boat.

The only guys I know getting 67-68 are running the Bravo 1 XS 26. One running 250 E-tec, the other 250 PRO XS. The Bravo 1 XS has thin blades, not very durable. Run it through a reef, sand, or mud once or twice and loose couple mph. And not just anybody can fix them..

My thoughts on this subject,

Why my boat isnt performing like his.
If I had the same boat that u have, boat motor prop fuel etc.
My question is, would my boat performance numbers be better, being that i weight 170lbs and the other person may way 230?

A Boat performance is based on weight right? Imo i think thats y the performance number are different. Correct me if in wrong. This is something id like to know

The weight of the person in the other boat is what we dont know? could this be y performance numbers are different? Does he weight more r less than me.

sent from my iphone slayer Galaxy NOTE II

That's why I added that whether I have 1/4 tank of fuel or 3/4 tank of fuel I am running about the same speed WOT, and that is a substantial weight difference. Im 190 pounds. All I can figure is that their configurations have zero fishing gear on board, no trolling motor, and fumes in the tank. If the SHO can spin a Bravo 1 XS I would be interested in seeing if there is any difference. I don't see it going 4-5 mph faster though?

It is possible to gain the speed with a bravo but holeshot will suffer....like stated before bravo is not a fishing prop,it is mainly for speed. Tweak the blades and it will be very hard to get it right again. That yamaha saltwater series is the best prop for a bay boat,the wide blades are designed to carry the weight of a bay or offshore boat. Take the trolling batteries and motor off if you want to gain speed.

1. What is the max rpm on your SHO
2 What is your gear ratio
It may be possible to get more from a more efficient prop but you must know what your current slip numbers are .
Factors that effect speed are hull design , weight, prop , setup and air temp.

Max RPM on the SHO is 6000-6100. I'm spinning 6100 at 63 mph. Gear ratio is 1.75-:1. Dry hull weight is 1950 lbs and motor is 505 lbs. My prop seems pretty efficient and I'm just starting to think the people who are claiming to run faster with the same setup are slightly stretching the truth. I talked to Kyle at LAM today and he even talked to Bill Kenner about it. Neither of them have heard of a BJ/250 SHO running over 63, so that may be question answered right there. I'd still be interested in running a bravo 1 XS just to see what it does tho...

Did they mention what conditions were when those numbers were achieved? My boat would run about 2mph faster with a slight chop.

Maybe alittle wax on that pretty black hull?

Haha it stays waxed. I guess I'm not putting enough to make a 5-6 mph difference though

Nope. But I'm assuming it was a hurricane force tailwind with a very strong following tide....

As a BlackJack owner, I also claim BS on those making such claims.

OK ... With this info you are at 9 percent prop slip. That is excellent for your boat !!! Optimum for your hull is 10 to 13 % and you are better than that. You would be hard pressed to do any better than this.
I have a Bravo 1XS, now this on a completely different hull so this is apples to oranges but it runs 14% slip on my boat. Now I do have another prop that runs 7% slip but it aint cheap.
The guys posting may be fudging some on their numbers. BUT You should do this just to see..... because I bet their numbers are with 1 battery, no trolling motor, 5 gallons of gas, on a 40 degree morning. (important)
Go do this and see what it does..... Then let us know.

I went out one morning while it was 36 degrees when we had all that cold, nasty weather. Water temp was 49 degrees. Very light chop on the lake. 63.8 mph that day and I had 1/2 tank of mostly premium fuel, 4 batteries, trolling motor, fishing gear, and just me (190 lbs). I'm thinking with 1 battery and no trolling motor (which is useless on a fishing boat...I'll never leave the dock like that) that 65 mph may be achievable, but definitely not the 68 these guys are claiming.

Sniper, which hull and which motor are you running that Bravo 1 XS on?

Modified Tunnel Merc 300XS