1997 Landau 1650 need more speed

[Landau1650]

Hello, I have a 1997 landau mv1650 with a 2007 Yamaha 90tlr.
I have tried several props, I am currently running a 13x19p Yamaha aluminum prop. I am seeing 41mph at 52-5300rpm with no load at all. Boat handles well but seems very slow to me. Hole shot is amazing. I have heard of similar hills running 50-60mph with the same motor so I am wondering what I can do to get some more speed out of mine.
I am running a big tiller, two 75lb batteries up front, 12 gallons of gas and cranking battery toward the back. My speed and rpm changes very minimally with more gear added.
Compression is 115 on all cylinders, and motor runs great, just wondering if anyone has any advice for how to get more out of my hull or if I’m maxed out.

 

[jimmbo]

Welcome to iboats

What is the WOT range for your engine? and what Rpms are/were you getting with the prop(s)?

Few 16 ft boats will get any where near 50, let alone 60 mph with only a 90hp. 41 isn't bad for a 90hp on a 16 ft,

 

[Bob_VT]

Welcome to iboats!
I have a Starcraft SS16 and the sad truth is - if your hull is aluminum it will go slower then a fiberglass with the same exact set up. 41 is near perfect for your set up. The "other boats" that are faster probably are not hauling the same weight ........... you are good

 

[airshot]

Prop the engine to give it max wot rpm with just you onboard. Power trim and tilt will allow you to trim to the max mph...thats all your gonna get, unless you go bigger on the engine. You will need lots more hp to just gain a few mph...normally not worth it!!

 

[QBhoy]

I’d be quite sure the guys claiming 50 and certainly 60, are telling tall tales ! Not a chance. You’d need her mounted sky high and with a cleaver. 50 may be achieved with a bit of work…but 60 is going to be a tough one for sure. To see 60 in the water is a serious barrier to get to. It takes about getting on for 200hp on boats only a couple of feet longer and with serious hulls too.

 

[jimmbo]

At higher speeds above 60mph, not much of the hull remains in the water, and handing becomes dicey

 

[Scott Danforth]

with max RPM's of your motor in the 5000-5500 range, getting 5200-5300 RPM is about perfect.

if you want more speed with the current 90hp. you need to either put the motor on a hull built for speed, or put the boat on the trailer and pull it with your truck

 

[Landau1650]

Thank you to everyone for your replies and insight. I guess I am just maxed out for this hull. I used to have a 50hp Yamaha that would push it 33 so I am very surprised to have only gained around 10mph after upgrading to a 90hp.
Both two strokes of around the same year

 

[jimmbo]

Usually a jump from a 50 to a 90 yields an 8 mph increase, you actually did good

 

[QBhoy]

Can’t emphasise enough how much proportional power to speed gain is required, to see any real speed gains through water…especially when it comes to anything around or over 50. As @jimmbo says earlier…it takes serious power and hull ability to achieve and deal with speeds like that. This is my boat running around mid 60’s gps. Hardly any hull in the water. She’s around 1500 kgs, stepped and pad hull keeping her manageable. She’s 18ft and a bit over 300hp

 

[jimmbo]

I just hate it when it starts Walking.

 

[Scott Danforth]

I just hate it when it starts Walking.

Chine walk will make you pucker the upholstery

 

[airshot]

Due to rivets and hull shape, aluminum boats do not do ultra high speed well at all !!! If you can reach mid 40's consider yourself very lucky.. Kinda like a drag racing car, it costs about 100K to break into the 200 mph bracket, but another 200K to get to the 225 mph bracket....sometimes not worth all the extra time, effort and cost to gain a few mph !!

 

[jimmbo]

Chine walk will make you pucker the upholstery

Hey, a Butt Clench on the Seat kept me from being thrown out of a Van when I rolled it.

 

[QBhoy]

I just hate it when it starts Walking.

Mine is amazingly rock solid at its top speed. Think the pad helps. Can literally take your hands off the wheel at 67 mph, if I was silly enough. But I’ll admit I got a real fright one day…was running flat out and high…next to a friends supercharger ski…paying too much attention to him to notice the wake from a 40ft cruiser that had went past long ago…the boat took off skyward and slapped its back end hard when it landed…nose took a dive. Was close to disaster. I cam off the seat and hit my head on the stainless bars of the canvas spray hood cover. Might have been out the boat if not for that. Silly boy. Normally fairly careful otherwise!

 

[jimmbo]

As neat as it is to watch the Ocean Racers take Air and land, it doesn't feel all that much fun, when it is you and your boat doing it.

My Hull, well my boat's hull, doesn't have a Pad

 

[Texasmark]

Welcome to iboats!
I have a Starcraft SS16 and the sad truth is - if your hull is aluminum it will go slower then a fiberglass with the same exact set up. 41 is near perfect for your set up. The "other boats" that are faster probably are not hauling the same weight ........... you are good

Not necessarily. I had an all stock rig: 17 1/2 Fishmaster Travis Edition Bass Boat With a 2002 2 stroke 90 Merc running a Ballistic 13+x24P at 56-5700 RPMs kissing 50 GPS. Avatar is a picture of the wake.

 

[Texasmark]

I just hate it when it starts Walking.

I had a 16' 11" Ranger 680C Ranger Fisherman with the high deadrise, standard Ranger 6" setback transom (from the end of the pad), and pad like their bass boat series, just a higher deadrise at the transom and narrower width.

Ran a 1988 tower of power 115 with an original 24P Laser. On my first outing with that prop, the boat got up to 55 and started Chine Walking.
Scared me! I finished the trip at a lower speed and when I got back home I traded the prop for something with less pitch...forget the number. That prop ran out at 6k RPM and kissed 50. I could slalom ski behind it weighing 235 roughly. The Laser being ported, gave me a good hole shot on the slalom. On the ported subject, when running alone at full throttle and close attention to the proper trim, when the boat would get up to enough speed for the ports to close, it was like the old "3 on the tree" stick shift cars with overdrive. It would lock up, the boat would shoot forward and the RPMs would drop down under the increased load as the speed continued to rise. I had a lot of fun with that rig.....sold it because I wanted a bigger boat to fish larger bodies of water.

 

[Bob_VT]

I think I will also throw this into the mix............ saltwater boating can be faster then freshwater............ think about that!

 

[jimmbo]

I think I will also throw this into the mix............ saltwater boating can be faster then freshwater............ think about that!

That has been known for many Decades