installing #4,s
#1
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installing #4,s
I busted one drive #4 small shaft with one inch spacer 1.33.1 ratio . I have found 2 new #4 big shafts with no spacer and 1.4.1 gear ratio. How much differnce in prop to compensate for gear ratio and how much difference in prop to compensate for no spacer. These drives have a #4 upper and a #5 lower. I needed to gain about 500 RPM,s anyway . I was spinning 31 inch 3 blades 4900. New motors peaked at 5600-5800. Well what do you think ?
#2
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You can use the spacers on the big shaft drives if you like ,the shaft thickness is the only difference.
1,41 :1 to 1,33 :1 is about 5 % prop speed difference.
I think you drop 200-300 rpm with the ratio.
So IMHO there is a 1-1,5 pitch difference.
Are you sure you still have prop bite enough without the spacer to come in plane ?
A #5 lower is a whole different style lower and will not fit a #4 or #3 upper due to different style shafts/gears.
good luck Stirling
1,41 :1 to 1,33 :1 is about 5 % prop speed difference.
I think you drop 200-300 rpm with the ratio.
So IMHO there is a 1-1,5 pitch difference.
Are you sure you still have prop bite enough without the spacer to come in plane ?
A #5 lower is a whole different style lower and will not fit a #4 or #3 upper due to different style shafts/gears.
good luck Stirling
#8
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Ok,that makes sense,I was thinking how you can swing such large props with those gears,that has to be a cat or a fast V with big torque numbers.
I have a set # 4 ssm here that is now in my garage for 4 years ,I,m still thinking to put them in a hull with a pair 572,s
or a pair all aluminium Italian V8,s with twin turbo,s ,we bought it out of an aluminium CUV here ,they stopped racing with years ago.
I still have a 31 Scarab viper that is empty,but don,t know if that hull is capable for big horsepower ?
I could only found some with twin 502,s or 454,s .
stirling
I have a set # 4 ssm here that is now in my garage for 4 years ,I,m still thinking to put them in a hull with a pair 572,s
or a pair all aluminium Italian V8,s with twin turbo,s ,we bought it out of an aluminium CUV here ,they stopped racing with years ago.
I still have a 31 Scarab viper that is empty,but don,t know if that hull is capable for big horsepower ?
I could only found some with twin 502,s or 454,s .
stirling