RLW

Merc 250 EFI outboards

I wouldn't be surprised if they were a 1:86:1 ratio.

dan lawrence

mike 1:75 gear ratio I own these motors. I was running bravo 28's which gave me good midrange 4,000 50-51mph. matt worked a set of maximus 30 props for me and i picked up 2mph. we are not done yet!

Spectre 28 Dan

throttleup

Mike,

I remember working on those props. Lightning Bay didn't tell me who the props were for or much about the boat. They just wanted the cup added to reduce the rpm.

Cup will increase cruise speed but frequently at the expense of top speed. Cup is water resistance. To gain top speed you want to run with as little cup and as much pitch as possible. Look at a Hering prop and notice that the tips have no cup.

Of course every boat is different and some boats need a little cup. Some boats more than others. Sometimes adding a little cup to the tips of a Hering prop does wonders, sometimes not. It's all about spending the time to try many different props and cup configurations to find the one that works best.

Dan's boat is coming along nicely, we are working with the diameter on his Maximus props and the boat is responding well.

For top end your boat would do better with a little more pitch and less cup but it will reduce the cruise speed a couple mph.

Matt

shifter

Matt,
Is the pitch an average across the blade?
Is the root diameter the pitch line?
If you reduce the diameter does the pitch go up?

Several of my customers are very happy with your work. Keep it up.
pat W

throttleup

Depending on the blades style the pitch can change in different area o the blade.
Speedmaster style props may have a constant pitch and the pitch can be the same anywhere on the blade. With a Bravo style blade the blade typically have pitch progression. The pitch of the blade increases as you go from the leading edge to the trailing edge. You can also see pitch changes when going from the hub to the tip of the blade.

When we measure pitch we use a computer and typically scan 5 different radii. The pitch measurement is an average of all the different radii.

The pitch does not increase when the diameter is decreased, especially with a speedmaster style prop. In the case of Bravo style props the pitch could decrease as the diameter is decreased depending on the blade design.

Pat, it's always a pleasure working with your customers.

Matt

Jonas

i want my cake and eat it too,,
i have pretty high slip i feel my cruise speed is way low
i thought going to the p5x's could solve that but??
i am running 31 hydro 5 blades now
35 fountain 02 680hp + per side,,
previous owner ran 5 blade herrings and got 107 ish out of it with the 31 's i see maybe high nineties but that is wringing its neck rpm wise.
still want to be able to get on plane too though...
soo all i want is
1, more mph on top end,,
2, higher cruise speed for sure,,
3, dont want it to be harder to get on plane,,

throttleup

You're not asking for much????????????????????????????????????????????

You've got mail.

MAtt

Jonas

i know i thought that was funny.. i know have to sacrifice something..
i wanted to meet u guys in florida,, i saw julie in your trailer but she was awfully busy at the time,, at the oso party it was so packed and crazy but fun couldnt get it done there either,.

i think u guys should show up out here for one of our events like bridge to bridge speed shoot out or big cat.. no one out here really does the labbing that i know of and i am pretty into it..
the calif delta is prob one of the best boating places in the world,,

Jnewton

Hi Julie and Matt...
I'm here in Indian Rocks Beach with a new 42 Lightning that needs to be "dialed in". I wrote to you briefly before and you suggested lengthening the XR drives an inch... we did that. What's the spring break about? I hope it's when I'm in town... let me know more details.
Thanks - JNewton

Jonas

how did it work out lenghtning the drives an inch???
what was the end result ????

i am thinking about doing the same to get better slip #s