Thanks for the feedback I am going to start working on one for my boat. Just curious about your exhaust did you fab up all the piping?

richard b wrote:
All you ask and a lot more are on the first part of the build process here :
www.modelgasboats.com/forum/14...-the-hull-too-/

After many pipe mount options explored, settled on 2 RCMK swing arm mounts mounted between box compartments. Due too way they mounted had to straddle the bulkhead having one of the 2 screws on each go against bulkhead on a pair of 3 1/2" support struts. One placed each side of bulkhead too distribute load and hopefully keep mounts intact and durable.

Figured out my crankcase cooling .... forget trying to use water cooling cylinders upsetting flow rate between jugs and find a fresh source

Drag tube off side of tub having only the tips last 1/8" in the water.
If drag on tube is excessive ? no worries tubes semi flexible nylon and will just bend backward under the pressure ending up shallower yet

Looks good Scott.
Just hope they pick up enough at high speed.
I had often wondered why no-one had put a pickup in or behind the turnfin?
Might not be a good idea had just wondered as I hear people tuning these to plant the inside sponson in a corner.
Maybe a tube welded to the rear of the turnfin with just the bent/angled tip exposed to the outside or below the turnfin bend if its a bent fin.

Ozpulse wrote:
Actually that was my original intent to have a tube right against turn fin on the inside right above water line so when cornering the water climbing fins face wound ram up the tube. After looking at the plumbing involved getting water picked up then across the gap between bracket to tub into case fitting figured had to be a simpler solution.

earthsurfer wrote:
Thank you ...

Can't take all the credit tho, Andre in Germany did the killer rudder assembly as a custom for the project. The billet pipe mounts are RCMK pieces.
Billet turn fin parts and the rest within build off my machines done in house.

3rd damn weekend in a row after nice weather M-f it's going to blow like hell and rain more on my days off ... Twin Rigger STILL a virgin ... Damn it !!

I feel your pain Scott! The ice has finally all melted away here, yet no break in site to even get out with some boats. Just too darn busy! It will be a while yet for me!

Doug,
If we raced GX class engines here would pursue playing with reeds once again.
I have built some real flame throwers in years past built as a test of my skills that i could ... sure enough, they did and quite well at that.
This one done near 15 years ago !!







This started life as an ECHO SRM2500 .... single coil & flywheel swap off a Mariyama trimmer engine, Pyramid reed block from a Homelite Super XL chainsaw, Special built Boysen fiber reeds, Modified WYK 33 carb, Custom head button.
Case induction was Piston port AND case induction via a passage from floor of intake tract into lower case. 2 eyebrow boost ports adder on roof on intake tract.
Engine ran like stink !! ... but did not last too long because port area was so chopped up offering little ring support chrome went away pretty quickly.
It did however twist up near 17K and had tons of torque .... O'well, it was fun back in the day.

As for the TWIN RIGGER, here it is finished up and how it looks ready for its first pond day ...