S pipe length

[Rick Sowell]

looking for a good starting point for the S pipe, SGX, Nova 21, 7port. what is the go to length? Thanks, Rick

 

[shoboat]

Rick,

I would try 7 and 5/8ths to 7 and 7/8ths.

65% nitro, .006" head clearance.

Enjoy Testing,

Mark Sholund

 

[Rick Sowell]

Mark, thanks for the reply, I have it set right now at 8in to the rear edge of the band, it is about 7.5 at the center of the band, will have to see how it works from there. Thanks

 

[shoboat]

Rick,

These measurements would be from the center of piston to center of both cones

on the pipe. 7.5" center to center may be a touch short for that pipes volume. Are

you running stock or modified propellers? With reduced cup and a little under 46 mm

In diameter you should be in the ballpark.

I run a OPS 29/40 pipe at 7.5" with a .312" stinger on a Valvola 21 and it

Does real well on this set up.

Thanks,

Mark Sholund

 

[Rick Sowell]

Mark, I am running some of your props, 1445 at 3.3 and 3.6 te cup. they had been doing good with the old nova small black pipe. I can always pull it some and try it.

 

[shoboat]

Rick,

The SGX used to like 1445's with 3.10", 3.21", 3.33", and 3.46".

Much more cup than that, it would not spin up to the moon with

very short pipe lengths.

Have Fun Testing,

Mark Sholund

 

[Rick Sowell]

Mark, I looked last night at the specs on those props, they were 3.33, and 3.46, I have the pipe at 8.25at the center of the band, I will see sunday if it works.