ProBoat HyperSport 48 Gas Mono - Prep for Racing

[Darin Jordan]

I'm curious, which trim tabs are you using? If unknown, no problem, I can eye ball it.

Thanks. -Mick

I think they are SpeedMasters, but I don't really know. I just had them laying around and got them in a bunch of parts someone sent me...

[Darin Jordan]

Completed a new throttle assembly this weekend. Started with a Dubro 4-40 sized throttle cable and an RC Car style ball end assembly. After mounting the ball into the throttle shaft plate, I modified the female portion to shorten it a bit and soldered the threaded end onto the cable.

I fabbed a new throttle bracket out of much thicker aluminum, which also allowed me to move the cable slightly to help with alignment.

The cable ends were purchased from Warehouse Hobbies. They use the fuel tubing to hold the cable housing in place. I added some panduits (zip ties) to ensure that the housing would stay put.

I removed the radio box, added a piece of reinforcing carbon to the exit point, and installed the other cable housing end.

With everything in place, the thottle action is more precise and holds idle much better.

After some testing and breakin, I'll get to work on the tuned pipe.

[Darin Jordan]

Here is a cell phone video that my neighbor took during my first test run today. Didn't capture much of the full throttle stuff, but the boat ran really well. Hull runs VERY light in the water... but really stable. Initial prop was an ABC 2514/3. Handling was really nice, even in the rather choppy water today.

After the second run, the boat slowed some, and when I got it back home, the spark plug was very loose, so I suspect that was the issue. I'll go over all the carb settings and such just to make sure, but the plug color looked really good.

Can't wait to put some more time on her!

This is a .mpg video, so you'll need Quicktime or the appropriate plugin to play.

HyperSport 48 first run

[AndyKunz]

You're slacking off, Darin. That wasn't in my e-mail in-bin this morning. I think I'm going to have to talk to somebody about your team membership

Andy

[Darin Jordan]

You're slacking off, Darin. That wasn't in my e-mail in-bin this morning. I think I'm going to have to talk to somebody about your team membership

Andy

Sorry about that... it's a crappy video... so I didn't think it was worthy!

[crabstick]

Hi Darrin, not sure what type of pipe you are going to fit, bit a Quickdraw Deep Vee Hotpipe would give you very good bang for buck.

[Darin Jordan]

Hi Darrin, not sure what type of pipe you are going to fit, bit a Quickdraw Deep Vee Hotpipe would give you very good bang for buck.

Thanks... I have an M&D pipe here that I may put on it, though I'm also considering trying a different one... we'll see when I get to that point.

[crabstick]

with the DV hotpipe you will be able to keep the pipe inside the boat and still have a fair bit of room for pipe length adjustment


This is a Cat, but you get the idea. see there is still plenty of room inside the boat for the external muffler even

[Darin Jordan]

Well... I figured out why I experienced a sudden loss of power/speed when I was out testing...

Starting fitting things for the new tuned pipe, and found a little item in the exhaust outlet... That explains it.

Worked out a way to fit a standard racing pipe on here, but it's going to require a 110-degree header, or something similiar, to wrap the pipe back around towards the radio box. Chasing down parts... news at 11:00...

I may look into that QuickDraw DV Hotpipe... Looks like that would be an interesting option...

[mickvk]

Are you going to GPS it before and after? I would be curious to know the difference. Thanks.

[Darin Jordan]

I didn't bother to GPS it before... It was doing like every other big gas RTR does... around 40 or so with an aftermarket prop...

Got the pipe install finished last night. Pretty simple and quick to do. Fabbed some mounting brackets to run off the existing hardware. Drilled them up and layed a little polish/buffing to it, just because I could.

The header pipe is a 7/8" 105-degree Stainless header and No-Leak flange from CC-Racing (http://www.cc-racingengines.com). Pipe is an M&D (http://www.mddracing.com/) with integrated muffler. The extra muffler on the end there is a ProBoat Miss Bud 1/8th muffler. Just put it on to make sure it would fit, but likely won't be running it. Shouldn't need to anyhow.

Just have to finish plugging the factory exhaust hole in the side of the hull, and hook the water lines back up, and she's ready for the lake.

Would have liked to have the exhaust tucked up inside the hull a little nicer, but the cleanest way to do that would have been to purchase a $350.00+ QuickDraw DV QuietPipe, and that's a lot of bread. Plus, it's not as flexible for testing/trying other pipes for tuning, especially once I go to a Mod motor...

[Darin Jordan]

Here are a couple more shots showing the whole thing...

[mickvk]

Nice work. I guess it's not a sleeper anymore!! :)

[bigcam406]

great work!

[Darin Jordan]

Made another small update last night...

I added a water exit port to the back of the hull, using a rectangle of plywood and some brass tubing. Drilled a 3/16" hole in deck at the back of the hull, just to the left of the center "hump", and epoxied the brass tubing into a 3/16" hole in the plywood. Then glued the plywood into the hull with the brass extending through the hole in the deck. I put in a pair of stainless screws just for good measure.

I then added a tap to the exit of the muffler and ran the water line up to this tap.

Not sure if this is the way it's "suppose" to be done, but I'll give it a try. At least until some Gas expert comes along and tells me I'm all wet and should have done it another way...

It's already fairly quiet. This should help quiet it a little bit more.