Anyone out there with Twin 150 Yamaha Motors?
 

Looking for some perfomance data from guys running twins on their 23' Tsunami or Sceptre.

Thanks, Jason

Re: Anyone out there with Twin 150 Yamaha Motors?
 

I have a 23 Grady Gulfstream with twin 150 Yamahas. The performance data on that is a cruise speed of 30-33 and top of around 47. The gulfstream has an identical deadrise at the transom and is a heavier boat so your performance would be similar I would "GUESS".

Re: Anyone out there with Twin 150 Yamaha Motors?
 

Thanks for the input! I was hoping for a 30 kt cruise. Top end doesn't mean much to me. How about fuel numbers?

Thanks again fot the information.

Re: Anyone out there with Twin 150 Yamaha Motors?
 

I have twin 1998 Yamaha 150 Salt Water Series engines. They have carb's and like gas alot. They are on a 23 foot SF SeaCraft. I may average around 1.5 miles per gallon (if I'm lucky).

Re: Anyone out there with Twin 150 Yamaha Motors?
 

Thanks for the info. I'll put my numbers up as soon as I splash the boat.

Jason

Re: Anyone out there with Twin 150 Yamaha Motors?
 

PeterB, What props you running? What type of load do you carry.

thx, Jason

Re: Anyone out there with Twin 150 Yamaha Motors?
 

Jason,

I have stainless steel 17-M props.

For boat weight I come up with around 5,600 pounds

(boat & t top = 3000 pounds) + (2 engines = 838 pounds) + (mostly filles 150 gallon gas tank = 900 pounds) + (3 fisherman and other misc stuff = 600 pounds)

Also, I use 12x12 Bennett trim tabs

What was the question again? Hope this helps.

Re: Anyone out there with Twin 150 Yamaha Motors?
 

Thanks for answering my question. I too have the m-17 props. I have the same fuel, same motors (not installed yet). I have a Tsunami. I will be considerably heavier with scuba tanks. Just trying to see if i'll be propped right.

Jason

Re: Anyone out there with Twin 150 Yamaha Motors?
 

Oh, and I get up to around 5,400 RPM's at WOT

Re: Anyone out there with Twin 150 Yamaha Motors?
 

So what kind of performance numbers did you end up getting?

Re: Anyone out there with Twin 150 Yamaha Motors?
 

Sorry, didn't see your question. They aren't on yet, deck goes back on this weekend. Alot of fishbox, transom and additional stuff to do.

Got an offer on these two motors, it's more than I paid so I'm toying with the idea of the new 175 4stroke Suzuki's.

Tempting, very tempting.

Jason

Re: Anyone out there with Twin 150 Yamaha Motors?
 

I JUST BOUGHT 135 OPTIS FOR MY SCEPTER I WOULD LIKE TO SEE PICS OF YOUR TSUNAMI. ARE YOU CLOSING THE TRANSOM WHAT KIND OF FISH BOX DID IT COME WITH 150 GAL TANK I THINK NINE HAS 100 BUT I HAVENT MEAS YET I STILL HAVE ALOT OF CUTTING TO DO ON THE FLOOR I WAS JUST GOING TO GET IT READT TO SPLASH WITH MINIMAL WORK AND MY WIFE AND I DECIDED TO DO THE RITE THING THE FIRST TIME AND HAVE SOMTHING FOR OTHER BOAT OWNERS TO ENVY THE BEST RIDE IN THE WATER! POST SOME PICS I'M WORKING ON GETTING PICS OF OURS TO POST IT IS A FAMILY PROJECT DUE TO PROMISE TO OUR 2 DAUGHTERS WHEN THE BOAT IS DONE WE ARE TAKING TO THE BAHAMMAS CANT WAIT
RUSTY ANXIOUS OWNER AND SEACRAFT LOVER

Re: Anyone out there with Twin 150 Yamaha Motors?
 

http://www.classicseacraft.com/forum...b=5&o=&fpart=1

Best of luck with your rebuild!!

Post photos.

Jason