Top Speed Tunnel setups ?

[MikeP]

Hi,

Anybody have some good Topspeed tunnel setup tricks? A friend gave me a new bare hull and I thought I would give it a try, they look like they handle rough water pretty good. Going to put a piped OS on it. Would like to know a good CG location and any mods to the sponson bottoms.

Mike

 

[ggillman]

Mike,

I got a bunch of them, but I got a service call to eastern Kansas and gotta scoot,

On the Intlwaters main page at the bottom, click "View all News Items" and scrool way back to my Topspeed buildup article, a few are there.

If ya got any questions I should be back Friday,

Gene ;D

 

[Jerry Dunlap]

Mike,

In 2000, I built five Top Speeds and took them to the IMPBA Internats in Moline, IL for two IROC type races. Last week, we ran the boats at the 2002 NAMBA Nats in Springfield, OR.

Here's what I recommend for the Top Speed:

1. Add 5 oz. of lead to the front of the cowling. To do this, cut a 1"X1" access hatch in the bulkhead just ahead of the radio box. Mix up 5 oz. of lead(bird shot or small pieces of lead work fine) and epoxy and pour it into the nose. Set the boat nose down while the epoxy cures. Then cover the access hatch with a piece of mylar or some material to seal the front.

2. Set the propeller depth about 1/4" above the bottom of the sponsons when the boat is resting on a flat surface with the back of the sponsons touching the flat surface. Don't be surprised if the sponsons don't touch evenly. Everyone of my boats was slightly warped, but they still ran o.k.

3. The prop thrust angle should be paralled with the sponson running surface, or slightly negative.

4. A good prop is the Octura X440. The black nylon prop that comes with the O.S. 21 Outboard actually works pretty well. That's the prop all the boats used at the 2002 Top Speed Challenge.

5. I redid the top of the radio box because I do not like the method used to tape the radio box lid to the the radio box . Wrapping tape over an edge doesn't provide a very good seal. I think I have some pictures of the modification I made to the radio box top. If I can locate them, I'll e-mail you the change. It's not that the method used in the kit won't work, I just think there's a better way. Hey, I just found the prints of the change I made to the radio box lid . E-mail me your address and I'll send them to you.

6. Be very careful that raw fuel does not stay in the fuel tank compartment at the rear of the hull. I've seen several Top Speeds destroyed because raw fuel attacted the fuel tank compartment :'(.

7. The only way to actually get a final trim on the boat is to run it. Once you get to that point and experience any problems, you can contact me directly.

Good luck,

Jerry Dunlap

 

[MikeP]

Thanks, for the quick responses. They will be very helpful to get going. I have searched the forum and found some talk here and there on the topspeed. I think the topic will help all who run this hull, there are a few out there.

Jerry my email address is [email protected]

-Mike

 

[ggillman]

Mike,

Jerry covered the bases for the Topspeed very well,

Bout the only thing else I could add is mine was one of the early versions and the radio box was very thin, so I made one outta ply, I did use the speed strips on my sponsons, Great little hull.

Gene ;D

 

[MikeP]

Hi,

Do you use shoo goo to glue in the wood servo trays?

I need to find something for speed strips or something to sguare up the edges. I would like to spread some kind of glue on there and sand it out square but not shure on PVC. Would it be best to buy PVC material? Looks like the stumble blocks could use some squaring up too.

Man this hull is sure wide.

Mike

 

[ggillman]

Hi Mike,

The hull is made of ABS plastic, I would leave the stumble blocks alone, they worked fine on mine as is. As far as the speed strips, try your local hobby shop or supply house that carries lexan or plexiglass, they should have some ABS sheet or scraps from a large sheet, or can order it for you. I believe the size you will need is .060 or .080 thickness. I used thick CA on my servo trays.

Gene ;D