Speedmaster 21

[Ale Oldini]

Hi guys, I've just finished my father's mono 21, it's a speedmaster powered with a Novarossi, and we use 20% nitro, pipe is a CMB (I think)

We tested it with a plastic prop (dia 38mm 2 blade) and more or less, it works fine, then we tested an octura x440/3, but in the straight is a little bit big and in the turn the revs go up.

Have you any suggestion for another prop?

Here some PHOTOS of the boat.

Regards

Ale

 

[Scott Norris]

Nice looking Boat! Great Job! An X440/2 or an X437/3 should be good choices. Also if the engine is New it will take a bit for you to see its full power potential. This recomendation is based on the high nitro content that we are using here in the US. With 20% you might need to back off to a X437/2.

 

[SayMikey]

Nice looking Boat! Great Job! An X440/2 or an X437/3 should be good choices. Also if the engine is New it will take a bit for you to see its full power potential. This recomendation is based on the high nitro content that we are using here in the US. With 20% you might need to back off to a X437/2.

I run a short stroke Nova Rossi Orlic mod and run a x437x3 tons of rpm. Some guys use bigger wheels but a stock prop sharp will work good.....Mikey

 

[Terry Keeley]

Nice job!

Over here we run x440/3 mostly, some run the x447/3, thats with 60% nitro though so the x447/3 might be better for you. How long is the pipe from the middle of the motor to the weld? It looks a little long...

ps: where did you get that full engine cover?

 

[Ale Oldini]

Thanks guys! I'll follow your advices. For the weekend I'll start to reduce the diameter of the x440/3 while I search the other props.

The pipe is long, if I remember well is 22cm (8,6 inch) but in this moment is better because my father prefers a good trotteling, on sunday he will have his first race!!! (62 years)

The engine cover is my father's design, he made the model, the mold and finally the hatch.

Ciao Ale

 

[Terry Keeley]

Yes, 8.6" is long but will give great throttleability like you said. Shorten it up to 8" os so when he gets used to the boat.

Very nice work on the hatch!

 

[shoboat]

Ale,

X-437/3 with 3.21" of cup and it will be much better. Keep shortening the pipe until you get

to 8". The X-440/3 is too big and the 20% will like the 37mm propeller. If you can find a ABC

dealer, try the 40 x 52/3 it works very well also. I have both in stock if you need them.

Thanks,

Mark Sholund

 

[Ale Oldini]

Thanks everybody!

mark you got mail.

Ale