Supercharged AKN

[Tyson Anderson]

Hello everyone,

I am new to the world of go karts and engine mechanics and am currently building my first go kart. I have a 205cc 1953 6.2 hp Wisconsin AKN I'm rebuilding to put in it. But I would like more power for my kart because my friend is building a go kart also with a 10hp Koehler and I cannot let his go kart be faster than mine, so I will need to find a a way to boost mine. Does anyone have any suggestions or advice? I was thinking of superchargeing it with a smog pump, has anyone done this? Thanks for all the help.

Sincerely,

Tyson

 

[bob58o]

Some good stuff here
http://www.elsberg-tuning.dk/supercharging.html

 

[landuse]

Welcome to the forum!

 

[Tyson Anderson]

Does any body have any ideas on how to make the carb work under the pressure? (Other than building a box around it)

 

[bob58o]

I'm planning a drawthrough set up with a miniblower to avoid that.

 

[anickode]

What is your mechanical experience?

The way I see it, if you just want a more powerful engine because your buddy has one, best bang for your buck will be to go buy a Predator 420 or find a bigger used engine. Something that will have readily available, relatively inexpensive aftermarket parts available.

By the time you source the parts, figure it all out, get it working decent, then blow it up and have to do major repairs or buy a new one because supercharging an engine that wasn't meant to be supercharged and getting significant reliable power gains out of it isn't really a project for amateurs... you could have just bought a bigger engine to begin with and spent the extra time racing go karts with your buddy.

I don't think you have the right motivation behind this project. You want a bigger engine, not a bigger project. A job like this needs to be driven by a desire to achieve something for yourself, not a need to one-up someone.

I could be totally off the mark, and if so, I apologize.

 

[65ShelbyClone]

I don't think you have the right motivation behind this project. You want a bigger engine, not a bigger project. A job like this needs to be driven by a desire to achieve something for yourself, not a need to one-up someone.

^This^

I have an AKN too, but it has the big chain speed reducer box and a funky crank to go with it so it just sits. There is a lot of potential with the industrial build quality, forged aluminum rod, knarly magneto, and big tapered crank bearings, but everything would have to be custom made for such an old engine with no aftermarket.

It's really a terrible option for what you're proposing unless you have the resources to do all that very costly custom work.

Does any body have any ideas on how to make the carb work under the pressure? (Other than building a box around it)

Yes, but the Zenith(?) carb is a non-starter unless you can find a solid float for it. The brass one will likely collapse under boost. A blow-through carbed supercharger is also going to be a lot harder to set up than other arrangements.

 

[anickode]

Yes, but the Zenith(?) carb is a non-starter unless you can find a solid float for it. The brass one will likely collapse under boost. A blow-through carbed supercharger is also going to be a lot harder to set up than other arrangements.

a blow-through carb is really a massive over complication for a small engine, as you're starting to get into pressurized fuel supply (greater than the 1 or 2 psi a pulse pump me get get you), which requires an electric fuel pump, which requires an electrical system, which likely requires parts for your engine that are either unavailable or very expensive.

Either way, you'd need to buy a larger carburetor.

Although it's a bit more complicated than this, to get the kind of power you're looking for (10+hp from a 6.5hp engine), you'd need to shove at least 2/3 more air and fuel through the engine, which means 10psi of boost, minimum. To do that, you'll need a substantially larger carburetor.

There's a WHOLE lot more to this than bolting a junkyard smog pump to the side of the engine and hooking a hose to the carb inlet.

 

[Tyson Anderson]

Thanks for all the input and surprisingly quick responses. I did not think this would be easy but hopefully I can do it cheaply because my budget for this project is not big. Expertise is not much of a problem (I would be lost on my own but I have someone with years of experience helping me every step along the way).

More of the motivation for this project is my need for speed and my will to learn, going faster than my buddy would just be a big bonus.

My engine has the marvel scheblar carb. (I'm not a very good speller)I have been told this is the better one but I think that I will still need to get a better setup, any suggestions? EFI would be great but I don't that's happening or even being considered. Due to costs and it being very difficult to accomplish on this engine. Has anyone ever done a similar project?

---------- Post added at 10:44 PM ---------- Previous post was at 10:42 PM ----------

P.S. I am also not going to buy a different engine.

 

[anickode]

Thanks for all the input and surprisingly quick responses. I did not think this would be easy but hopefully I can do it cheaply because my budget for this project is not big. Expertise is not much of a problem (I would be lost on my own but I have someone with years of experience helping me every step along the way).

More of the motivation for this project is my need for speed and my will to learn, going faster than my buddy would just be a big bonus.

My engine has the marvel scheblar carb. (I'm not a very good speller)I have been told this is the better one but I think that I will still need to get a better setup, any suggestions? EFI would be great but I don't that's happening or even being considered. Due to costs and it being very difficult to accomplish on this engine. Has anyone ever done a similar project?

---------- Post added at 10:44 PM ---------- Previous post was at 10:42 PM ----------

P.S. I am also not going to buy a different engine.

Ok that clears things up a bit.

There aren't really very many successful forced induction industrial engines out there at all, let alone on here.

Realistically, you can probably get that thing into the 8-10 hp range just by bypassing the governor, upgrading the carb, opening up the exhaust, and putting a thinner head gasket on it - maybe use some dead soft copper sheet and make one, if you can't find different thickness pre-made ones (unlikely)

To what extent are you rebuilding the engine? My big concern would be that on an old tired engine, it will need nearly a full rebuild just to make it a candidate for modding.

Main bearings
Rod bearings
Piston rings
Valve job
Breaker points and condenser
Inspect the cam

Next big question is whether or not the flywheel is safe to over-rev. Getting more HP usually entails making the engine spin faster, and the last thing you want is for that flywheel to come apart at speed. Might as well just put a claymore behind your seat.

I'm not trying to destroy your plans here, just trying to help, and possibly persuade you to just to a basic restoration of this cool old engine, and save the power modding for something a little bit more user friendly and replaceable.

 

[Randy H]

How about one of those small nitrous kits. Gives you bragging rights. A fairly inexpensive way to blew your engine up.

 

[Tyson Anderson]

Thanks again for all the input. The governor has already been dealt with, the engine has no exhaust now but I will straight pipe it. The head gasket is way thinner than it used to be I am looking for a bigger better carb I could put on it. The engine was my grandfathers and he almost never used it so it's not very tired. We are doing a valve job though. We are not opening up the crank case because there is nothing wrong in it. We think that valve float will govern the engine before the flywheel comes off.

 

[anickode]

Thanks again for all the input. The governor has already been dealt with, the engine has no exhaust now but I will straight pipe it. The head gasket is way thinner than it used to be I am looking for a bigger better carb I could put on it. The engine was my grandfathers and he almost never used it so it's not very tired. We are doing a valve job though. We are not opening up the crank case because there is nothing wrong in it. We think that valve float will govern the engine before the flywheel comes off.

Did that thing use an air vane governor in the fan housing? If so, you're all set. If it uses a flyweight governor inside the case, you might want to remove it altogether and plug the hole, to eliminate the possibility of it flying apart inside the engine.

How does the cylinder wall look? And have you done a compression test?

As for a carb, if you have the resources to make your own adapter (intake manifold), you can bolt up pretty much anything that's of an appropriate size. 22mm mikuni, etc. Heck, even a GX270 carb might be a good option.

 

[mckutzy]

You mean, you hope the springs allow you to have valve float before something's goes awry...
Just because they're there... Doesn't meant that they're going to react the same, say as in a clone type engine..

How do you know the con rod will handle more than the intended speed you want to put it through?...

What kinda speeds and overall goal of this engine "upgrade".
Let see some pics of the intended use motor

 

[Tyson Anderson]

It used a fly wheel governor and I did remove it and then plug the whole. The cylinder wall and piston are in surprisingly good shap. We will do a compression test after the valve job is done and we put it all together. I will probably use any better carb I can find, hopefully I don't have to make a adapter. I know that the carb from my buddies 10 hp Koehler would work without an adapter so maybe I could find something like that.

 

[ezcome-ezgo]

If it doesn't work out, I'm sure Kelly Wood would buy that engine. Suits his style.

 

[Tyson Anderson]

I will post pics in a couple of hours. The engine normally operated at 3600rpm so I don't want to go to far past that. I would be very happy if my go kart went 40kmh but it's not doing that without a few upgrades I think.

---------- Post added at 07:59 AM ---------- Previous post was at 07:57 AM ----------

Should I know who Kelly Wood is. Lol

 

[ezcome-ezgo]

Should I know who Kelly Wood is. Lol

If you are interested in karts, look up some of his posts. The karts he builds are unique.

 

[Tyson Anderson]

This is what came up on google images. Lol
https://cdn.instructables.com/FQC/TTEQ/GTQVSVQ8/FQCTTEQGTQVSVQ8.LARGE.jpg

 

[anickode]

I will post pics in a couple of hours. The engine normally operated at 3600rpm so I don't want to go to far past that. I would be very happy if my go kart went 40kmh but it's not doing that without a few upgrades I think.

---------- Post added at 07:59 AM ---------- Previous post was at 07:57 AM ----------

Should I know who Kelly Wood is. Lol

40k? Shoot, you can do 40kph with a bone stock governed 5hp. Should be no problem for you at all.

Kelly wood does a lot of vintage inspired builds, and has a penchant for unique stuff. Got a real good eye for blending styles.