170 MONTAUK, 90-HP Four-stroke - Moderated Discussion Areas

  ContinuousWave
  Whaler
  Moderated Discussion Areas
  ContinuousWave: Whaler Performance
  170 MONTAUK, 90-HP Four-stroke

search | FAQ | profile | register | author help

Author Topic:   170 MONTAUK, 90-HP Four-stroke

Nauti Tauk posted 04-04-2007 08:56 AM ET (US)
There have been numerous posts about how to prop a Montauk and what WOT will be. I've been tweaking our 170 MONTUAK with 90-HP four-stroke Mercury for a month or so and here's what I've come up with:
--Engine raised three holes (one from the highest)
--18-inch pitch Vengence prop with #2 cup added by prop shop.
With 22-gallons of fuel and just me, the maximum speed is 45.4-MPH at 5,900-RPM in fresh water. In saltwater it would be a little more. Trimmed for top end and around 45-MPH the little girl starts to get somewhat light and wants to chine walk, so I don't keep it there long. Mid-range is 31.2-MPH at 4,200-RPM. I would love to try a 20-inch LazerII.
jimh posted 04-04-2007 09:06 AM ET (US)
Please explain the measurement system you are using to gauge the amount of cup added. What is "#2 cup" and how does it differ from #1 and #3?
Tom W Clark posted 04-04-2007 09:15 AM ET (US)
If you are trying to get the most form your boat and motor, forget the out dated Vengeance. Buy a Laser II or a Stiletto Advantage I or Turbo I.
I have a couple 20" Laser IIs. You can try one if you like.
Nauti Tauk posted 04-04-2007 12:03 PM ET (US)
A prop tech I aint! The shop that did the work for me,Bobby Soles in Florida, said that by adding #2 cup it would drop my rpms to compensate for the higher engine position,and it did. The cupping supposedly makes the prop "bite" better and help keep it from blowing out. I was turning over 6000 before the work and the rpms dropped to 5900 and my midrange speed increased at a lower rpm. I really don't know what a #2 cup denotes other than it did what he said it would. Tom, thanks for the offer to use the LaserII. If you think it'll make enough difference to warrent the expense I'll hold onto my allowance for a while and spring for one. Thanks
jimh posted 04-04-2007 11:25 PM ET (US)
I also have no idea what you mean by a "#2 cup."
I wonder, does "#2 cup" have any meaning to anyone?
Nauti Tauk posted 04-08-2007 07:19 AM ET (US)
Jim,found out what #2cup designates: When the prop shop adds cup to the blades of a prop they have a template that's used to be sure the amount on each blade is the same hence the numbers refer to the template used.
jenkinsph posted 04-08-2007 02:52 PM ET (US)
I agree with the laser LL 20" pitch. From the performance
specs on the Whaler site. Looks very good at 46.6 mph and
cruise mpg is great too.
Steve
Teak Oil posted 04-08-2007 09:01 PM ET (US)
Which 90hp Mercury do you have, carbureted or EFI?
Nauti Tauk posted 04-09-2007 07:54 AM ET (US)
TeakOil,
2003 90 four stroke(carbs). So far it's run like a little top. From the threads I've read maybe I'm lucky. This will be our first summer with this boat so it'll get alot of use exploring the lakes in Georgia. This time next year I should know for sure how well the carbed version is going to do. Thanks for the input on the Lazer 20". Will have to wait until some money frees up to buy one but it's on the list now.

Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.

Author	Topic: 170 MONTAUK, 90-HP Four-stroke
Nauti Tauk	posted 04-04-2007 08:56 AM ET (US) There have been numerous posts about how to prop a Montauk and what WOT will be. I've been tweaking our 170 MONTUAK with 90-HP four-stroke Mercury for a month or so and here's what I've come up with: --Engine raised three holes (one from the highest) --18-inch pitch Vengence prop with #2 cup added by prop shop. With 22-gallons of fuel and just me, the maximum speed is 45.4-MPH at 5,900-RPM in fresh water. In saltwater it would be a little more. Trimmed for top end and around 45-MPH the little girl starts to get somewhat light and wants to chine walk, so I don't keep it there long. Mid-range is 31.2-MPH at 4,200-RPM. I would love to try a 20-inch LazerII.
jimh	posted 04-04-2007 09:06 AM ET (US) Please explain the measurement system you are using to gauge the amount of cup added. What is "#2 cup" and how does it differ from #1 and #3?
Tom W Clark	posted 04-04-2007 09:15 AM ET (US) If you are trying to get the most form your boat and motor, forget the out dated Vengeance. Buy a Laser II or a Stiletto Advantage I or Turbo I. I have a couple 20" Laser IIs. You can try one if you like.
Nauti Tauk	posted 04-04-2007 12:03 PM ET (US) A prop tech I aint! The shop that did the work for me,Bobby Soles in Florida, said that by adding #2 cup it would drop my rpms to compensate for the higher engine position,and it did. The cupping supposedly makes the prop "bite" better and help keep it from blowing out. I was turning over 6000 before the work and the rpms dropped to 5900 and my midrange speed increased at a lower rpm. I really don't know what a #2 cup denotes other than it did what he said it would. Tom, thanks for the offer to use the LaserII. If you think it'll make enough difference to warrent the expense I'll hold onto my allowance for a while and spring for one. Thanks
jimh	posted 04-04-2007 11:25 PM ET (US) I also have no idea what you mean by a "#2 cup." I wonder, does "#2 cup" have any meaning to anyone?
Nauti Tauk	posted 04-08-2007 07:19 AM ET (US) Jim,found out what #2cup designates: When the prop shop adds cup to the blades of a prop they have a template that's used to be sure the amount on each blade is the same hence the numbers refer to the template used.
jenkinsph	posted 04-08-2007 02:52 PM ET (US) I agree with the laser LL 20" pitch. From the performance specs on the Whaler site. Looks very good at 46.6 mph and cruise mpg is great too. Steve
Teak Oil	posted 04-08-2007 09:01 PM ET (US) Which 90hp Mercury do you have, carbureted or EFI?
Nauti Tauk	posted 04-09-2007 07:54 AM ET (US) TeakOil, 2003 90 four stroke(carbs). So far it's run like a little top. From the threads I've read maybe I'm lucky. This will be our first summer with this boat so it'll get alot of use exploring the lakes in Georgia. This time next year I should know for sure how well the carbed version is going to do. Thanks for the input on the Lazer 20". Will have to wait until some money frees up to buy one but it's on the list now.