Sv-27/Stiletto outboard

[forescott]

I traded a blue sv-27 hull/hardware recently and decided I wanted to try an outboard on it. I have a Stiletto outboard with a ul-1 motor in it that I installed on the transom. the stinger was already gone and I loosened up the stuffing tube and slid it out. Filled up the existing holes with epoxy and had to re-drill the holes for the outboard mount and a new hole for the steering linkage, and one for the motor wires to enter the hull. The inside of the sv was super easy. The stock battery trays were already removed and I took out the motor mount plate. I was able to use the stock radio box/servo/and linkage. Installed a turnigy 120 and tactic receiver. I'm running a single battery straight down the center. 3s for fun, and 4s for speed. Laid down some velcro in front of the motor mount area and used velcro straps on the battery. Ec-5 plugs for connectors. Installed a transom mounted water pick-up for the esc. (Outboard has its own cooling setup for the motor) Thats pretty much it, it's ready to go!

First time out was pretty good. Tested with a 3s pack, and grim 42/55. The nose bounces quite a bit until it gets up to a decent speed. Turning response is incredible with the outboard! Cooling is working great with 12" stream of water coming from the outlet. Only thing is when I run it full throttle it grts some good speed-wobble. Even in flat water. I think the outboard is a little too low and I'm gonna raise the mount about 1/2 inch and get the prop shaft even with the bottom of the hull.

[kjohnsiii]

Dude, that is def different. I wonder if that motor is just a little to heavy back there. Where is your cog at?

[forescott]

About 20%. But its easily adjustable by moving the pack. Plenty of room to move it forward. Video soon to come!

[forescott]

If I can get this thing dialed in and am happy with it, I'm gonna transfer everything over to a brand new white hull, and put some stiletto decals on it. I think it would be a cool looking little crossover boat.

[kjohnsiii]

Nice! Vid would be great to see. Is she faster than the stock s/u?

[forescott]

I'm not shooting for big speed with this setup. Just a fun sport boat. If I hit 40mph reliably I'll be happy. I got another run in this morning with the motor raised another 1/2 inch. Its running better but I'm upgrading the steering servo and linkage because the outboard wiggles too much at high speed with the stock equipment. I also put a hobbyking turnigy typhoon 1800kv outrunner in the outboard to see how well it works. With the outrunner I dont need any water cooling on the motor and I lose a little weight on the back end. Pics to follow soon!

[forescott]

Here are some pics of the new setup. The typhoon outrunner leaves plenty of space under the outboard cover for air to circulate, plus the motor wires come out on the bottom right where they exit the o/b cover and now I don't have to splice on any additional wire to make it to the esc. I drilled a few holes in the top of the cover for more circulation.

Got the traxxas high torque servo installed with a larger diameter 4-40 rod but there is still play in the steering. I may have to order another stock steering arm for the stiletto and do something different with the steering.

Swapped out the turnigy 120 for a turnigy/seaking 60 from one of my venom boats. Should be plenty of esc for the outrunner.

[forescott]

Got a run in with the typhoon outrunner today on 4s. I really like this combo. The motor is fast and smooth with the 60amp seaking and temps were under 90 degrees. Handling was a little better with the high torque servo but there is still play in the linkage. I've decided to center the servo in the hull and drill another hole to the right of the motor mount for a second linkage arm. I think a dual arm servo horn with 2-steering rods connected to each side of the outboard is necessary to hold this outboard still @ speed. Cant quite get full speed until the steering issues are ironed out but it looks promising.

[Brushless55]

oh man, we need a video of this sucker

[forescott]

removed all the guts and installed a carbon servo mount on a piece of hobby grade plywood and epoxied everything in place for the new steering setup. Got another sv27 steering linkage set and a new stiletto steering horn to replace the one I cut. Feels pretty stout!!

[forescott]

Got a short run in with the new setup yesterday. Srill getting the chine walking @ high speed. At this point I think its a drive angle/height issue and I need to play with it some more to get it ironed out. Video uploading as we speak!

[Brushless55]

looking forward to the video!

[forescott]

Still needs a lot of tuning but its a start!

[Diesel6401]

Interesting. I like it! Do you think part of the issue maybe because the outboard sets the prop a lot further back then the stock strut. It looks more like torque roll, which may be related to prop size and distance away from the transom. Maybe a high kv motor with a smaller prop may help. Not sure what you have laying around. Just suggestions, I don't know ANYTHING about outboards.

[forescott]

It could be. I'm gonna try a 640. It's the smallest prop I have in 3/16 shaft. Then give it some pos. trim.

[shannon87]

hi scott nice work im planning a similar conversion on the motley crew afte rit comes out and ill race it stock for a while as the warranty is for like 3 months and it will give me time to get parts and i have enlisted someone to help but anyways i was just wondering how it tuned out as i would like somethin different also cheers

[forescott]

Turns out I can't get the outboard up high enough on the transom to fix the handling issues. At high speeds the outboard lifts the entire hull out of the water which is causing the side to side motion. I guess the sv hull just wasn't meant for the stiletto o/b.

[shannon87]

yer i noticed in vid sorry to hear about that but it looked awesome i asked grim and he said it wont work ill take his advice as its his boat so im goin to keep that inboard and try and hunt around for a suitable mono i was thinking about a deltaforce 29 or seaducer of some sort cheers for replying all the best and wished it worked out for ya

[forescott]

Yeah, the outboard needs a bigger hull. The sv-27 was a bit too small and light.

[shannon87]

lol but it still looked awesome haha i was speaking to grim racer and he said it would work with the motley which is what im going to get but i think im gunna leave it inboard as the layout is too cool.

He pointed me towards a prather mono hull from hyperformance as that used to be set up with an outboard from prather itself. But if i do a cat again ill get one from bby racing as he is happy do do a special setup to suit the outboard.

Anyways hope you do another outboard project i mean im not against tunnels but thats all you see that have outboards.

If only kyosho continued to make outboard boats or even AQ or PB that would be awesome to see outboard boats other than tunnels buzzin round the pond as i know heaps of people who would buy outboard boats other than tunnels lol all the best scott cheers

[D for Dummy]

I have a second Motley Crew boat that I'm thinking of building similiar to a UIM X-Cat (http://www.xcatracing.com/). although I suspect there are a little too big, I was hoping to use the outboard off my Stiletto plus purchasing another, however after a turtle strike at full speed last night I will be buying 3 outboards. (sheared off the skeg and damaged the housing ). Anyone else building outboard boats?

View my profile for links to Motley Crew and Stileto videos.