Question .... Sponson spacing ?

[Scott Schneider]

Need some help from you guys with BIG or TWIN rigger experience.

Just finishing up my big gas inline twin and need to set up sponson spacing to establish the best footprint for size of this boat ... Input please.

* Tub is 48" long at 5 3/4" wide, set up as a 3 point. OAL is 52", RTR weight going to be 22/23#, After plane distance is 32"

NEED INPUT ON SPONSON SPACING ???

Thanks guys,

Scott

Hull here: http://www.modelgasboats.com/images/fbfiles/images/DSCF0550.JPG

 

[Buckshot]

Scott,

I'd start around 20" to 21" from inside of sponson to inside of sponson.

Just my opinion.

Buck

 

[Luis Sanchez]

Scott:

My inline gas RCMK 520-s block inline Hurricane rigger is 38 and 3/4 inches long by 5.33" wide. I have a spacing between the rear part of the Sponsons of 17.25" . In the front part of the sponsons there is a spacing between them of 17.00" . The back riding surface of the sponsons are 3.5" wide. The skies are about 3/4" wide.

This rigger is at 74-75mph on last weekend short runs. It is truly stable at fast speed and takes the straight and turns very well. It weights RTR 19 pounds. It is running with two 23cc heads / pistons modded, and is pulling well and withouth a delay on the start my largest prop: ABC 3418. I know this can be hard to believe but truly this engine adapts very well to any combination of Cylinders/heads and pistons exchanges; i/e: 29cc, 26cc and 23cc. I have not try yet the 26cc heads / pistons yet.

Hope this help somehow since we are all "newbies" with respect to this newer style of inline gas double engine in riggers...

Luis.

 

[julianconde]

Nitro Twins are about 18-19 inch spacing. make sure that there's a difference of 1 inch form the right side and the left side sponsons.

julian

 

[Andy Brown]

Twin 90 SGX-2 is 19.5".