Laser II 19P now, whats next

[DanielR]

With the combo below I was expecting higher top speed. I've played with the prop selector app at mercury website and neither of the selections offers me 21P at the end. Since Im not familliar with props, which one and what size would give me higher top speed.

Current prop: Quicksilver Laser II 19P, it's an older model pretty beat up, 48-16544-A41-19P
Max 4400RPMs get me to 49mph, trimmed approx 51mph
Engine: New crate chevy 350, with edelbrock intake manifold
Boat: 1992 Maxum, 19ft bowrider

Thanks,
Daniel

 

[Tail_Gunner]

Re: Laser II 19P now, whats next

With the combo below I was expecting higher top speed. I've played with the prop selector app at mercury website and neither of the selections offers me 21P at the end. Since Im not familliar with props, which one and what size would give me higher top speed.

Current prop: Quicksilver Laser II 19P, it's an older model pretty beat up, 48-16544-A41-19P
Max 4400RPMs get me to 49mph, trimmed approx 51mph
Engine: New crate chevy 350, with edelbrock intake manifold
Boat: 1992 Maxum, 19ft bowrider

Thanks,
Daniel

Laser props are more of a bass boat type of prop.....4400 rpm is 2 low for that motor be sure your tach is on...Im sure its off...Try getting gps speed and get a tach that is accurate...and cheap ...boat tachs are worse than the best polotican...lies like rugs...

There should be a gear ratio stamped on the drive plz post it....This may sound like a hassle but ive never seen a poster go to the trouble to get it right and say now that was a dumb ideal...


That boat engine combo should do 55-60 mph

 

[DanielR]

Re: Laser II 19P now, whats next

Outdrive is Alpha One gen 2, 5.7, with 1.47:1 ratio.
You are correct on the RPMs, they seem pretty low. I have new set of gauges coming this season. Once I get on the water again Ill have them tested and will follow up on it.
The speed was captured by the gps, so it should be relatively close.

 

[zagger]

Re: Laser II 19P now, whats next

I run that prop on a 1700 SR Maxum, Alpha1 135HP in 21" pitch and loved it. Trimmed out it would go 52 on gps. Depending on the gear ratio of your drive but I would look at 21" pitch. The 17 was much lighter but then you are pushing more HP and if hole shot is little off you could adjust the size of vent holes on the prop.