asmund

Hello, I`m about to mount the STS .28 marine http://cgi.ebay.com/STS-28-PULL-STAR...item2eb21d8736 into my Thunder Cat 31, but I do not know which engine coupler I need that will fit the threads on the SG shaft and the 3/16" flex haft. Anyone out there who has ran a car or marine engine with SG shaft in a boat that can help me out ? I`m not familiar with the dimensions when it comes to inches and such, as we use the metric system around here

HendricX

First .. you need a flywheel .. ask seller if he has one that will fit that engine.

Second ... cut-off the flat part in front of the threads.

Third : Threads on engine are 1/4" x 28 .. collets in that size to 3/16" flex-cable should be easy to find.

(Aeromarine / Octura / Hydro & Marine) , best collet is one that has a step-down that will fit inside the flywheel.

You can buy the Octura in the Swedisch-[link=http://shop.miniracingteknik.se/html/flex_hex_1-4-28_gaengad_axel_till_3-16_flex_(476mm).705.html?osCsid=e313dfc192c8ab5b03 c214061e0f1418]webshop of MiniRacingTeknik[/link].

asmund

Great, thanks alot
I already have the special fly wheel and I know I must cut the shaft, once I get the correct collet I`m ready to go[8D]

rcguy1411

can you list of part numbers of all the parts and where you got them as i need to repower my TC 31 as well

asmund

The fly wheel I found on .bay, don`t remeber where. Engine and throttle linkage is in the link I posted above and the collet can be found many places on google or .bay. I was going to use the 0702 big bore tuned pipe that is designed to be used on the STS .28 and .30 engines, but it will not fit into the hull because the radio box is in the way. I`m going to use a header from an old buggy engine and the stock TC 31 pipe instead.


Did a quick search, scroll down here and you will find both the flywheel and the collet (flex shaft coupler) : http://www.ozrcboatsupplies.com/jae21g.htm
:

Here`s also the flywhell and if you use the search function in there for "collet" you will find that one too: http://waterandairhobbies.com/advanc...ywheel&x=0&y=0

rcguy1411

thanks for the the links gives me another rout to go with repowering the TC 31 other than stock as i dont want to spend alot to get her back up and running as this is the boat i grab when i dont have alot of time to go out and run hope to here how yours run maby a vid

asmund

I made it to 45 miles on the radargun with the "stock" engine after alot of experimenting. It was heavily modified though, port and polish, bigger carb, no head shims, new prop octura M445 (polished, sharpened and ballanced) reamed out and shorted header, and some mods to the hull and rudder.It was really screaming at the time, but now that I have met the wall with this engine I want to start over again with a different engine and see how much I can squeese out of it. There`s alot of relatively inexpensive and powerfull car engines out there that can be used once you have the correct collet and flywheel. If I see potentional with this STS, I think I will buy a Picco .28 P3 which is amongst the most powerfull car engines and try it out. Water-cooling isn`t actually neccessary as the cooling head will stick up enough to allow plenty of air running through it if the canopy is opened up a bit.
I have a video on our local forum, will try to link it in here

Here it is http://www.youtube.com/watch?v=z9yZFe9YggA

On this video I`m running a Just engines purple pipe, it is a very very quiet flatdisc pipe and you can se the carb (from a .91 aeroplane engine) But I sacrifice some miles to run quiet though. You can also see the rudder that has been cut/shaped and sharpened.

I think I`m around 42 miles here. Getting airborne at 5.30 min