Octura 1450 props

[LarryConrad]

Best prop on my boat so far has been a Barr cut 1450 massaged on the duplicator set Marty Davis designed, with a little additional cup on the trailing edges.(3.4") I let a buddy try the same prop on his hummingbird, and he wouldn't give it back! Next best prop is a 50X69 cupped to 3.3 I borrowed from Richard D. I'm not sure who worked that prop, It might be one from Mark Sholund. The real test comes in August when I run at Mendota against some of the best drivers and fastest 20 hydros in the country. Blackbird hydro, 5 port Nova, 3280@81/8" 70% home brew.

 

[Marty Davis]

Best prop on my boat so far has been a Barr cut 1450 massaged on the duplicator set Marty Davis designed, with a little additional cup on the trailing edges.(3.4") I let a buddy try the same prop on his hummingbird, and he wouldn't give it back! Next best prop is a 50X69 cupped to 3.3 I borrowed from Richard D. I'm not sure who worked that prop, It might be one from Mark Sholund. The real test comes in August when I run at Mendota against some of the best drivers and fastest 20 hydros in the country. Blackbird hydro, 5 port Nova, 3280@81/8" 70% home brew.

Did you get both duplicators? If so, you have done the correct thing to add a little pitch to the tips and trailing edge since you can not get the prop to conform perfectly to the duplicator and only a little difference makes a huge difference in performance.

Did you make a prop with an A and B Blade? If so, you have my best prop effort for a 21 rigger. You will find that unlike most props that have been modified, this prop will mill slow and also run fast. Much different than most props that you get from others who modify props. The secret to this prop is the outer edge that raises efficiency a ton and the slight change in the tongue pitch.

Now to enhance performance a little more, check to see which blade has a little more pitch than the other and index your drive line so that that blade is going into the water at the engine TDC. I have been told that I am crazy (by some very successful boat racers) and this does not work, but I can assure you that it does work and will make this prop even better. With two blades that are slightly different in pitch, this will make it really run well.

 

[Ron Zaker Jr]

Best prop on my boat so far has been a Barr cut 1450 massaged on the duplicator set Marty Davis designed, with a little additional cup on the trailing edges.(3.4") I let a buddy try the same prop on his hummingbird, and he wouldn't give it back! Next best prop is a 50X69 cupped to 3.3 I borrowed from Richard D. I'm not sure who worked that prop, It might be one from Mark Sholund. The real test comes in August when I run at Mendota against some of the best drivers and fastest 20 hydros in the country. Blackbird hydro, 5 port Nova, 3280@81/8" 70% home brew.

Did you get both duplicators? If so, you have done the correct thing to add a little pitch to the tips and trailing edge since you can not get the prop to conform perfectly to the duplicator and only a little difference makes a huge difference in performance.

Did you make a prop with an A and B Blade? If so, you have my best prop effort for a 21 rigger. You will find that unlike most props that have been modified, this prop will mill slow and also run fast. Much different than most props that you get from others who modify props. The secret to this prop is the outer edge that raises efficiency a ton and the slight change in the tongue pitch.

Now to enhance performance a little more, check to see which blade has a little more pitch than the other and index your drive line so that that blade is going into the water at the engine TDC. I have been told that I am crazy (by some very successful boat racers) and this does not work, but I can assure you that it does work and will make this prop even better. With two blades that are slightly different in pitch, this will make it really run well.

NOT CRAZY! Been indexing drivelines for 20 years,ever since the first time I went to Indy and you showed me.

 

[LarryConrad]

Best prop on my boat so far has been a Barr cut 1450 massaged on the duplicator set Marty Davis designed, with a little additional cup on the trailing edges.(3.4") I let a buddy try the same prop on his hummingbird, and he wouldn't give it back! Next best prop is a 50X69 cupped to 3.3 I borrowed from Richard D. I'm not sure who worked that prop, It might be one from Mark Sholund. The real test comes in August when I run at Mendota against some of the best drivers and fastest 20 hydros in the country. Blackbird hydro, 5 port Nova, 3280@81/8" 70% home brew.

Did you get both duplicators? If so, you have done the correct thing to add a little pitch to the tips and trailing edge since you can not get the prop to conform perfectly to the duplicator and only a little difference makes a huge difference in performance.

Did you make a prop with an A and B Blade? If so, you have my best prop effort for a 21 rigger. You will find that unlike most props that have been modified, this prop will mill slow and also run fast. Much different than most props that you get from others who modify props. The secret to this prop is the outer edge that raises efficiency a ton and the slight change in the tongue pitch.

Now to enhance performance a little more, check to see which blade has a little more pitch than the other and index your drive line so that that blade is going into the water at the engine TDC. I have been told that I am crazy (by some very successful boat racers) and this does not work, but I can assure you that it does work and will make this prop even better. With two blades that are slightly different in pitch, this will make it really run well.

NOT CRAZY! Been indexing drivelines for 20 years,ever since the first time I went to Indy and you showed me.

Yes Marty, I have the A-B set of duplicators,and the prop has an A and a B blade. I'll try indexing the driveline.

 

[shoboat]

Boaters,

The indexing may work, but I think it is something else

that contributes to the uneven propeller pitches.

How do you allow for the winding up of the shaft?

How big of cup or pitch difference are you using?

We have run some staggered pitches on our S.A.W.

boats and they can work if done properly. I think

personally the propeller is working better than the

indexing. We have learned quite a few different

modifications to the blade and profile that helps the

efficiency of the propeller.

Just Curious,

Mark Sholund

 

[mtruex]

Best prop on my boat so far has been a Barr cut 1450 massaged on the duplicator set Marty Davis designed, with a little additional cup on the trailing edges.(3.4") I let a buddy try the same prop on his hummingbird, and he wouldn't give it back! Next best prop is a 50X69 cupped to 3.3 I borrowed from Richard D. I'm not sure who worked that prop, It might be one from Mark Sholund. The real test comes in August when I run at Mendota against some of the best drivers and fastest 20 hydros in the country. Blackbird hydro, 5 port Nova, 3280@81/8" 70% home brew.

Did you get both duplicators? If so, you have done the correct thing to add a little pitch to the tips and trailing edge since you can not get the prop to conform perfectly to the duplicator and only a little difference makes a huge difference in performance.

Did you make a prop with an A and B Blade? If so, you have my best prop effort for a 21 rigger. You will find that unlike most props that have been modified, this prop will mill slow and also run fast. Much different than most props that you get from others who modify props. The secret to this prop is the outer edge that raises efficiency a ton and the slight change in the tongue pitch.

Now to enhance performance a little more, check to see which blade has a little more pitch than the other and index your drive line so that that blade is going into the water at the engine TDC. I have been told that I am crazy (by some very successful boat racers) and this does not work, but I can assure you that it does work and will make this prop even better. With two blades that are slightly different in pitch, this will make it really run well.

NOT CRAZY! Been indexing drivelines for 20 years,ever since the first time I went to Indy and you showed me.

Yes Marty, I have the A-B set of duplicators,and the prop has an A and a B blade. I'll try indexing the driveline.

good stuff guys..i am working on a prop of the duplicators marty, i am sure it will need pitch added for my boat since it likes a good bit more than it has off the duplicator, and that barr cut is pretty large..on another note sholund sent me a #2 profile 50x69 to try today and it runs really well..now i need to figure out how to go as fast after half straight as i come off the corners, comes out of the corner and 2 stages then richens up at half straight and starts cackleing..im going to try and restrict the water a little at a time and see if that helps.

 

[shoboat]

Martin,

I have the fix to that problem.

It will come in the next package.

Thanks,

Mark Sholund

 

[Marty Davis]

Best prop on my boat so far has been a Barr cut 1450 massaged on the duplicator set Marty Davis designed, with a little additional cup on the trailing edges.(3.4") I let a buddy try the same prop on his hummingbird, and he wouldn't give it back! Next best prop is a 50X69 cupped to 3.3 I borrowed from Richard D. I'm not sure who worked that prop, It might be one from Mark Sholund. The real test comes in August when I run at Mendota against some of the best drivers and fastest 20 hydros in the country. Blackbird hydro, 5 port Nova, 3280@81/8" 70% home brew.

Did you get both duplicators? If so, you have done the correct thing to add a little pitch to the tips and trailing edge since you can not get the prop to conform perfectly to the duplicator and only a little difference makes a huge difference in performance.

Did you make a prop with an A and B Blade? If so, you have my best prop effort for a 21 rigger. You will find that unlike most props that have been modified, this prop will mill slow and also run fast. Much different than most props that you get from others who modify props. The secret to this prop is the outer edge that raises efficiency a ton and the slight change in the tongue pitch.

Now to enhance performance a little more, check to see which blade has a little more pitch than the other and index your drive line so that that blade is going into the water at the engine TDC. I have been told that I am crazy (by some very successful boat racers) and this does not work, but I can assure you that it does work and will make this prop even better. With two blades that are slightly different in pitch, this will make it really run well.

NOT CRAZY! Been indexing drivelines for 20 years,ever since the first time I went to Indy and you showed me.

Yes Marty, I have the A-B set of duplicators,and the prop has an A and a B blade. I'll try indexing the driveline.

good stuff guys..i am working on a prop of the duplicators marty, i am sure it will need pitch added for my boat since it likes a good bit more than it has off the duplicator, and that barr cut is pretty large..on another note sholund sent me a #2 profile 50x69 to try today and it runs really well..now i need to figure out how to go as fast after half straight as i come off the corners, comes out of the corner and 2 stages then richens up at half straight and starts cackleing..im going to try and restrict the water a little at a time and see if that helps.

Your last sentence is EXACTLY why the boat is going rich. You need to restrict the water quite a bit. I am impressed at how fast you learn. Some of these things took most of us a LONG time to learn....

 

[Tim_Duggan]

My 1450 testing got delayed The engine was hurting plugs on a known set-up so it's new bearings time. The second boat had a radio issue so it just wasn't meant to be!

any news on the prop testing?

Hi Martin,

I had a motor issue in my boat resulting from the bearing change, then a major set-back (read crash). The boat required a new sponson after an impact, and I have a new set under construction. Also, my back up engine wasn't quite up to the task (couldn't pull same props) so engine #1 is going back together for more prop tests. I've been a little side tracked with two other class boats also.

 

[shoboat]

Marty,

I think Martin has had some good teachers that we did not have

20 years ago.

Thanks,

Mark Sholund

 

[Marty Davis]

Marty,

I think Martin has had some good teachers that we did not have

20 years ago.

Thanks,

Mark Sholund

Mark:

I agree, it was much more difficult then. But, I have to say that there are always mentors that share knowlege. Ed Hughey was one of my major mentors, and I appreciate what he taught me.

Martin grasps ideas very quickly and understands concepts very well. Might be his background..

 

[mtruex]

Marty,

I think Martin has had some good teachers that we did not have

20 years ago.

Thanks,

Mark Sholund

Mark:

I agree, it was much more difficult then. But, I have to say that there are always mentors that share knowlege. Ed Hughey was one of my major mentors, and I appreciate what he taught me.

no doubt i have had plenty of help from some smart guys..by the way one of them turned one of my novas around for me..it runs super!! thanks david B)

and the boat is orange not pink, dang cell phone cameras <_<

 

[shoboat]

Marty,

I know you have been a mentor to many over the years that I have been in the hobby.

We sure appreciate all the knowledge that you have shared also.

Martin,

So it looks like we are on the right track for your set up.

I have two more propellers ready to test, but I think I will try them first,

you have to get ready for work soon.

Read your email it solves your water problem.

Thanks For The Feedback,

Mark Sholund

 

[Marty Davis]

Marty,

I think Martin has had some good teachers that we did not have

20 years ago.

Thanks,

Mark Sholund

Mark:

I agree, it was much more difficult then. But, I have to say that there are always mentors that share knowlege. Ed Hughey was one of my major mentors, and I appreciate what he taught me.

no doubt i have had plenty of help from some smart guys..by the way one of them turned one of my novas around for me..it runs super!! thanks david B)

and the boat is orange not pink, dang cell phone cameras <_<

The engine now has 4 large bearings. How does it run?

Anyway, I ran a season with a Nova Rossi Outboard engine that I could then run "turned around" so the exhaust came out to the rear of the boat. Just took a square drive cable at the engine. Was a great setup. The MAC replaced this setup a week before the Sarasota Nats because it was much better.

 

[mtruex]

Marty,

I think Martin has had some good teachers that we did not have

20 years ago.

Thanks,

Mark Sholund

Mark:

I agree, it was much more difficult then. But, I have to say that there are always mentors that share knowlege. Ed Hughey was one of my major mentors, and I appreciate what he taught me.

no doubt i have had plenty of help from some smart guys..by the way one of them turned one of my novas around for me..it runs super!! thanks david B)

and the boat is orange not pink, dang cell phone cameras <_<

The engine now has 4 large bearings. How does it run?

Anyway, I ran a season with a Nova Rossi Outboard engine that I could then run "turned around" so the exhaust came out to the rear of the boat. Just took a square drive cable at the engine. Was a great setup. The MAC replaced this setup a week before the Sarasota Nats because it was much better.

the engine runs as good or a little better than any of my others, seems to turn more rpm so far with the same setup not really sure why yet..i also liked the mac in this boat but i dont think it was better than the nova,very close in all aspects, then again i didnt work with it much..it was STOK haha

 

[Norm Doerr]

Stoch! "Well right there's yur problem"

 

[Marty Davis]

Marty,

I think Martin has had some good teachers that we did not have

20 years ago.

Thanks,

Mark Sholund

Mark:

I agree, it was much more difficult then. But, I have to say that there are always mentors that share knowlege. Ed Hughey was one of my major mentors, and I appreciate what he taught me.

no doubt i have had plenty of help from some smart guys..by the way one of them turned one of my novas around for me..it runs super!! thanks david B)

and the boat is orange not pink, dang cell phone cameras <_<

The engine now has 4 large bearings. How does it run?

Anyway, I ran a season with a Nova Rossi Outboard engine that I could then run "turned around" so the exhaust came out to the rear of the boat. Just took a square drive cable at the engine. Was a great setup. The MAC replaced this setup a week before the Sarasota Nats because it was much better.

the engine runs as good or a little better than any of my others, seems to turn more rpm so far with the same setup not really sure why yet..i also liked the mac in this boat but i dont think it was better than the nova,very close in all aspects, then again i didnt work with it much..it was STOK haha

:lol:

 

[TERMINATOR]

blackbird 20 hydro, stck 5 port nova ops 3280 at 7 7/8 .. custom mix 70 percent , odonnell blue plug, sholund 1450 3.6 cup .....69 mph and more to go. what a great thread guys.

tk

 

[shoboat]

Terry,

How did the boat come out of the corners?

Can you squeeze the pipe in a little more?

You may want a 3.46" cupped 1450 also for when

the summer heat comes if ever. Appreciate the

business Terry. I am heading out to test some

new propellers today, it should be an interesting

test session with the options I made up. We are

having good luck with the ABC 50 x 69 also. The

profile #2 is working well on some set ups as well

as the 1914 from ABC. Ran some 1450's last test session

that were running mid 70's, but they were reduced a

little bit.

Have Fun Testing More Combinations,

Mark Sholund

 

[Marty Davis]

Marty

i'm with you, give me a 3 pound 21 rigger and i will go 80mph+

but in race conditions, with other boats racing around i stick with my 3-3/4---4 pound racing 21 hydro and happy to go 73mph+

but everyone is different...

p.s i can count on one hand how many 45 hydro's are even going 80mph in race trim in AUS....

Tim

back to topic,

i've seen 73mph+ with mod 1450, never run full blade, its all about those rpm's for me baby.....as you know...

regards Aaron

Aaron:

I have always run 20 boats that weighed around 3 3/4 lbs. I am putting the finishing touches on a new boat that will come in at about 3 lbs. Guess I will see if it will race in regular water. I believe that it will. I have refined my 20 boat to the point that any waves, etc the boat bounces straight up and sits right back down. The current 3 3/4 handles rough water better than any 20 boat that I have seen. I am optimistic about the new 3 lb boat. HOPEFULLY. this will allow me to run props that WILL race at 80+ mph.