w8ye

My Feedback: (16)

Here's one on a leaf blower gas engine. This guy didn't have the knowledge nor means that you do. But if you look through it, you may find some useful information that others presented. There's 125 posts to it....

http://www.rcuniverse.com/forum/m_32...tm.htm#3210902

Here's spindle of a turbine engine?

w8ye

My Feedback: (16)

This one is more of a discussion of theory on glow engines...

http://www.rcuniverse.com/forum/m_12...tm.htm#1213743

w8ye

My Feedback: (16)

http://www.rcuniverse.com/forum/tm.asp?m=926675 The pipe from the super charger to the intake on the engine has turned brown. Did it get that hot? Saito 72

horace315

My Feedback: (15)

An intercooler is essentially a radiator tuned for high flow rates and the increasing density of the charge as it cools. Most designs use ambient air for cooling, flowing through the radiator core, and often collocated with other radiators for oil or cooling fluid. An alternate design, often referred to as a charge cooler, uses water to cool the charge, then cools the water in a separate radiator. While heavier and more complex, charge coolers can often make arranging the rest of the engine much simpler.
we used to use the term outercoolers(old school mechanic) when the cooler was mounted in front of the radiators, and internal engine coolers intercoolers,they all used be called aftercoolers.i think now they all are referred to as intercoolers.

w8ye

My Feedback: (16)

This is a car engine....

http://www.rbinnovations.com/newsite...percharger.htm

w8ye

My Feedback: (16)

Villa

To design, build, and test a turbocharger requires knowledge, instrumentation, money way beyond what a modeler or tinkerer is capable of. The rotor you show in your photo looks more like the impeler on a water pump. The "boost" will be very low. The changes and improvemenbts needed to be succesfull are so small that without very good instrumentation (lots of money) you will never know which direction to go in your experimentation. Look at Post #51. The photo shows an axial compessor wheel on the left, and a turbo wheel on the right. Probably from a jet engine. The turbo wheel on the right is the shape that you need. Without the "bell"shape of the whole wheel and the scroll shape of the individual "fins" I do not believe you will have an increase in power. You need RPM on the magnitude of 300,000 +. Very dangerouse. I would suggest a different project.

BBW Walt

My Feedback: (11)

Doesn't it seem there's always an OLD GUY dragging back the enthusiasm of youth. You may be a pioneer of sort with this. With that said your already an excellent machinest. Be careful, keep going. If the power thing don't pan to someone else's level you've still done something here thats pretty cool. This is really neat...

ZZ

Post #51. The photo shows an axial compessor wheel on the left, and a turbo wheel on the right.

Actually, the turbine wheel "hot side" is on the left and the compressor wheel is on the right.

horace315

My Feedback: (15)

here is a good digram of a turbo set up maybe this will help some maybe not good luck.
http://forums.beyond.ca/showthread/t-13583.html
you may have to cut and paste.

proffcharlie

I'm impressed if for no other reason than you're willing to try. If you can get 1 lb of boost out of this setup that's a GREAT feat. I raced turbo Buick Regals at the drags for a few years and know the problems you are facing.

All I want to add is to remember that HEAT is the key to a turbo. In a good set up exhaust pressure is not what makes performance. A turbo uses the exhaust heat expanding across the turbine blade to accelerate the shaft and hence accelerate the compressor and product more intake pressure. For the most part it is easier to suck through the carb than blow in to it. Blowing in makes mixture control harder and usually results in pressure loss around the throttle barrel. Sucking through the carb also prevents the turbo trying to blow fuel back to the tank. If you get any real pressure out of the system I think this will be a problem.

Cooling the turbo bearings has been a problem on auto applications. Buick's answer was to have cooling fins on the bearing center housing along with high volume oil feed and a water jacket fed off of the cooling system.

Boost lag (spool up time) can be reduced by using a smaller turbine inlet pipe and a larger outlet pipe. Think in terms of increasing the exhaust gasses expansion rate across the turbine blade.

Good luck on this project. I hope you are getting some class credit for the work you are doing.

VeeAte

I have seen some intercoolers on cars that spray a fine mist of water and methanol onto the outside fins of the intercooler to get the air charge cooler. Not sure you could use nitro fuel cause of oil content. :P

Cant wait to see how this turns out. If all power expectations fail it will still look awesome.

forwheeldrift

yes. i have a nitro tc3 with a supercharged os .12TR... here are some videos of it.........http://www.putfile.com/forwheeldrift
the supercharger does not increase power at all, how ever it lowers the time it takes to reach top rpm limit .ie; the car has a top speed of 39mph without it and the same with the supercharger but, it gets to top speed about 20 feet sooner...it also is not efected by air temp or humidity, glow plugs last longer( befor the supercharger i was going thrue 2-3 plugs per gallon "really old and tired motor"
since i installed the supercharger i have gone threw 1 1/2 gallons and still the same plug...the tunig reliabilety is pricless

fly_nitro_rc

Well, I'm back again and out of school with some time to play with my turbo. Unfortunatly now that i am out of school i dont have access to the machines that i needed to fix the broken header but i could probably use some epoxy or something. I havent had a test since the first one in the winter but i do have some details about why my turbo worked. When the engine started for the first time with the turbo on it, the turbo spooled up and the engine seemed to run perfect with it of course until the header broke. I think the main downfall to my design is simply the size of the turbo to the size of the engine. Although the turbo did work on my MDS .68, im sure it would even work with an engine like a small weedwacker, or ever a lawnmower motor. I recently bought a turbocharger for my 91 honda accord (kind of my project car) and i then really relized the turbo/engine ratio. The turbo i made was simply too big, and im not sure if a feasable turbocharger small enough could be made easily.

It really was a neat project from the start, designing it alone was tough enough. I even had to design a way for the exhaust to flow internally so that it lubricated the two metal ball bearings.

Anyway it was a cool project and for now makes a really cool thing to have on my shelf.. haha, but if i ever do get around to fixing it and using it i'll make sure to post again.

tukkus

My Feedback: (2)

fly nitro rc....all you have to do to post a pic is click on "post reply"(do not use the fast reply, it doesn't work for posting pics)

it's under the last post made on the page.....when you click it, a new window will open for you to post in, and at the bottom of the window that you write in, you will see "click here to upload" ...click on that and another window will open with a bunch of "browse" buttons... click on one of the browse buttons and it will allow you to find your pic on your computer to upload, when you find the pic you want to upload click on it then click "OK" ....you also have to write something in the post otherwise it will not work for some reason

i don't know why but they don't make it very clear on how to post pics in these forums

tukkus

My Feedback: (2)

i also have a MDS .68..... the only way i can get it to run good is to use 5% and a Fox idle plug.... when i tried running it with the stock plug and 15% nitro it just ran like crap and deadsticked on me everytime.... i then changed the fuel and plug and now i dont have any problems with it...i have read that others had the same problem as i did so i tried what some had recommended and it worked..... i'm wondering if it will ever work properly for you with the plug and fuel you are using, have you had the engine in the air yet?

fly_nitro_rc

Hey back once again...

My MDS has always run very reliably for me. I have had the engine in the air many times.. and in the ground many times yet it always runs perfectly. I am still using the same glow plug that came with my engine, but im sure any standard OS glow plug would be fine. I normally use Byron originals 15% nitro fuel with great success.. in fact i can usually flip start it with a chicken stick, and it starts on the first or second flip. In times of need I've even used some RC car fuel (most people says its a big no no but i dont see the difference so long as there is enough lubrication) that is 20% nitro (byron originals) and that has worked fine too.

I would say you just need to adjust your engine right. Return the low speed needle to the factory settings (im not sure what they are), and open the high speed maybe 3 turns or so and it should start. Ive noticed with this engine in particualar that you can really play with the high speed and the engine still runs. Even at like 5 or 6 turns out it stays running... rich of course.

And as always if it doesnt readilly start just replace your glow plug.

I had my engine recently on my giant size PBF and i wasted probably an hour trying to start it before i figured i just needed a glow plug - that fixed the problem because it started right up with the new glow plug.

w8ye

My Feedback: (16)

Here are Preston's pictures..

tukkus

My Feedback: (2)

I guess you are one of the lucky ones that can use 15-20% nitro and not need a idle plug...i've tried every setting possible before i switched the fuel and plug and nothing worked... I have YS/OS/Satio/K&B engines and they all run according to what the manufacterer recommends but the MDS 68 simply runs better with the 5% fuel.

Do you have any other projects in mind?

dhal22

i believe my uncle turned a .91 OS ducted fan with a tuned pipe around and used a prop to pull one of his own designs over 200 MPH. this was clocked by radar in the early 90's. he stillhas the plane. obviously it was/is a extremly lowprofile aerodynamic plane. seems a lot easier to have a lot of speed and power that way than with a big turbo tied to your engine. the rpm's on a ducted fan engine are insane.

fly_nitro_rc

Tukkus- I do have other projects in mind, however i have since graduated from high school and am attending UTI in Illinois, and cannot use the machines anymore.

However I really want to get the turbo running again for a good test, and i just need to get the header fixed. I will try to see if someone at the high school would like to fix the header for me so I can get it running again (The header just needs a thicker pipe leading to the turbo from the engine, and also this time i WILL incorporate a brace to hold the turbo to the engine so that the weight is not all on the outlet pipe (why it broke in the first place)).

If all goes well i may be on here at the end of the week with a reply of a test run assuming the header gets fixed. I'll be sure to post anyway, now that i am on break i have alot of time again.

-Preston

fly_nitro_rc

dhal22- your right, the turbo is NOT the best way to make power, but since people wanted a turbo i made a turbo.

HLovato

Im big into turbos with all my cars, real and Nitro. I have made alot of custom turbo kits for local cars here and am starting on the mini size modles now. These pics are from a turbo someone else built but i have made one about the same and done alot of little changes to make it live longer. The main is to seal the ehaust from the bearing center. i have been using single sealed flanged bearings and leave them open where they face each other. I have drilled a small oil hole and use a perry pump to draw fuel out of the fuel tank and through the center of the turbo to cool and oil the bearings. the turbo can be make smaller becouse of the curved impellor and turbin. basicly this original desine is perfect but the center had to be redesigned for lubricating. Also i make my turbin from stainless but leave the impellor aluminum. the turbin and shaft are one piece. I do ballance the assembly as best i can becous nomatter how good you think the machining is its not perfect. Even the car and heavy equipment are ballance and they use multi million dollar tooling to make. the good turbo companies (ie Garret,IHI,KKK,Holset) use sound waves to ballance the set up. anyways enjoy the pics and ill have some new ones soon i hope........Hal

22Ryan22

if ya wanna buy superchargers. rbinnovations.com

sljensen

My Feedback: (6)

Never mind. Sorry