Blackbird 21 build thread

[aaron alberico]

Chris

with the valvola [i had the 07 version] run a h7 at about 45mm about 3.4-3.6in cup and a pipe at 7-1/4 on 70% fuel

that should get you there,

let us no how you go

i think as you stated your set up will be alot different to what you have been running,

as you will need to set it up for alot more rpm's, less prop, shorter pipe that what you run on your nova,

regards Aaron

 

[Chris Wood]

hey aaron,

ya i think that is route i am going to take.

i prefer octura blades over abc for my boats.. i will try some more abc but i think a 1445 or so is what i am going to like.

will let everyone know in a few weeks when the arctic blast here in the armpit of the usa quits LOL!!!

chris

 

[dave roach]

Chris

What you will find is the timing no. are to high.

Dave Roach

 

[steve wood]

ChrisWhat you will find is the timing no. are to high.

Dave Roach

not on the new motors. 182 exh 123/126 intakes

 

[Chris Wood]

yep that is low for what we run

chris

 

[aaron alberico]

yep, i would consider them to be low too..lol :lol:

 

[shoboat]

Aaron,

That propeller profile looks familar.

As does the boat that it is on.

Hope Things Are Going Well For You,

Mark Sholund

 

[aaron alberico]

Mark

spot on...lol :lol:

things are going very well

will give you a call tomorrow

here is a pic of the boat Mark, O and a future boater [My boy Jayke]

regards Aaron

 

[Chris Wood]

UPDATE!

just spent 9hrs testing today. ya i know i am retarded lol

testing the valvola some more.

started off this weekend with some motor mods done earlier in the week.. sleeve work. head work timing work.

had some improvements.

started with a 1445 45.85 dia 3.3 pitch.. might as well cut the grass with that.. run 62mph pipe lenght was 7 1/2 inches.

pitched it up to 3.6. same pipe lenght.. maybe 1 mph gain. shove the pipe to 7" again maybe 1mph gain, nothing major.

so i put a h-6 on.. pitched to 3.4.. JUNK.. had some chatter, didn't turn very well ect. put more pitch in it and didn't help.

put the 1445 back on. if my memory is right the best we got was 64 or 66 i forget. decided to dig in my box and see whe else i had. Found a 1450 that my novas didn't care for. WoW what a difference. ran 70 out the gate. could'nt get any more out of it but i think after we do some more motor work we will be in the ball park. Boat launched really good all day. pull off the bank good.

I think after we do some more motor work and we get good water and air i think there might key word MIGHT be a 73-75 in this thing.. we will see.

I was shocked it pulled the 1450.. but it did again and again.. it wasn't a fluke. SO with that being said i just wanted to update anyone that has followed this thread, and hope in a week or two i will have more info.

Oh temps were around 78-80 degree's and not sure what air density was.

I will keep everyone posted once i get more time on the motor

chris

 

[shoboat]

Chris,

Glad to hear that the 1450's are still alive and well on a 21 Hydro.

Now to find a pipe that works better with your port timed areas,

and you will be as fast or faster than the Nova set up.

There is still more in the 1450 propeller so keep trying different

combinations until you hit it. You are closer now this past weekend.

I wish I could test for 9 hours,I am JEALOUS!!!

Thanks For Sharing,

Mark Sholund

 

[Richard Dahlheimer]

Chris,
Glad to hear that the 1450's are still alive and well on a 21 Hydro.

Now to find a pipe that works better with your port timed areas,

and you will be as fast or faster than the Nova set up.

There is still more in the 1450 propeller so keep trying different

combinations until you hit it. You are closer now this past weekend.

I wish I could test for 9 hours,I am JEALOUS!!!

Thanks For Sharing,

Mark Sholund

Hey Chris, after sending you a pipe mount to try with your Nova, you go and switch motors! Well, thats the younger generation for ya.lol Interested to know the specs on the 1450 that you could pull with the CMB, but not the Nova? Interesting thread, and thanks for sharing your test results. Richard D

 

[Chris Wood]

Chris,
Glad to hear that the 1450's are still alive and well on a 21 Hydro.

Now to find a pipe that works better with your port timed areas,

and you will be as fast or faster than the Nova set up.

There is still more in the 1450 propeller so keep trying different

combinations until you hit it. You are closer now this past weekend.

I wish I could test for 9 hours,I am JEALOUS!!!

Thanks For Sharing,

Mark Sholund

Hey Chris, after sending you a pipe mount to try with your Nova, you go and switch motors! Well, thats the younger generation for ya.lol Interested to know the specs on the 1450 that you could pull with the CMB, but not the Nova? Interesting thread, and thanks for sharing your test results. Richard D

lol hey richard.

havn't switched yet.. i am just trying this out so i can get a feel for it.. alot of people ask about that motor in my boat and what to do with it so i decided it is time to find out.

i run 1450's on my boat with a nova. and so far seams to be good on the cmb

48mm dia 3.21 pitch.

a little less than i run on my novas but i think that is O.K. as long as i get to the same point.

i have high hopes this weekend as i think or should i say HOPE that the changes we are doing to the motor this week will put us in the mid 70's.. 70 aint bad but it ain't good enough either. so we will see.

i will keep everyone posted and if anyone has anything else to add PLEASE feel free to chime in on this.. as this motor is a fresh start for me.

chris

 

[shoboat]

Chris,

The 75+MPH Propellers are on the way.

Thanks,

Mark Sholund

 

[Scott Norris]

Chris,
The 75+MPH Propellers are on the way.

Thanks,

Mark Sholund

I'd like to have one of those Mark. Running a Valvola in a Roadrunner Ultralight. Does OK but would like to see 75 in heat trim!

 

[John Knight]

Chris,
The 75+MPH Propellers are on the way.

Thanks,

Mark Sholund

I'd like to have one of those Mark. Running a Valvola in a Roadrunner Ultralight. Does OK but would like to see 75 in heat trim!

Put me down for one also. Can't have Scooter catching me!

 

[Ray Sametz]

Pipe dreams :blink: :blink:

 

[shoboat]

Ray,

You are so right,it will take some pipe tuning to get up into the mid 70's.

The intake timing and port timed areas will need more work also. The

propeller and pipe & motor combination all have to work in harmony

with one another to get up to that speed. One other area that will need

to be addressed is the propeller blade area ratio,but this is another thread

guys.

Keep Trying Different Combos,

Mark Sholund

 

[Chris Wood]

Chris,
The 75+MPH Propellers are on the way.

Thanks,

Mark Sholund

lol thanks mark

i will let you know when i get them done and tested.. hope they work

just would like to see 72-74 and i would be happy..

chris

 

[Terry Keeley]

Chris,
The 75+MPH Propellers are on the way.

Thanks,

Mark Sholund

lol thanks mark

i will let you know when i get them done and tested.. hope they work

just would like to see 72-74 and i would be happy..

chris

And that speed, in heat racing trim (not loose and flopping all over the place), would prolly put you in the top 1% of all 20 hydros in N. America.,, :blink:

 

[shoboat]

Terry,

Chris is just trying to keep up with his Dads 45 Hydro.

I think Chris is in the 1% now.

Getting any nice weather up there in Canada lately?

Keep On Testing,

Mark Sholund