Dyno it or its all just useless hand waiving and eye-catching diagrams. Do a real dyno test, with a decent graph and list all the important things like boost pressure and how much more fuel efficient it is.
See I'm with the people who talk about blowing the pressurized air straight through the combustion chamber and out the exhaust. You need to prove that the shock wave holds that pressure.
well the shock wave does hold pressure back to a degree, speaking from knowledge of motocross 2 strokes, but without a exhaust specifically tuned to make this happen i would say that amount of pressure is finite. with larger 250cc two strokes the reverberation of the sound shock wave drives the A/F mixture back into the combustion chamber during the on set of the power band, this is whats called "on the pipe" in two stroke world. but again, just how much this shock wave can hold back is the real question here.
The timing is the same (intake and exhaust openings overlapping) whether the engine is supercharged or not. This is nothing new, and as the guy explains in the video the tuned pipe is important to minimize that. But nothing changes on this by adding a forced induction system. BTW, almost all 4-cycle engines also have overlap in their valve timing, including the supercharged ones.
Matthew Miller But so even if it created any type of boost, wouldn't that boosted intake also require some sort of boost fuel to enter with the mix? If anything the added pressure would force back the fuel into the tank! LOL
Wow, this came up from the past! Fuel in a carburetor is pulled into the airstream by the low pressure in the venture (that's supposed to be an "I" on the end of that word, but for some reason it keeps autocorrecting!). If a supercharged and carbureted engine is a draw-through design (carb upstream of the compressor), this doesn't change: the carb is still seeing ambient pressure and the fuel supply needs no changes. If the engine is a blow-through design (carb downstream of the compressor), the carb is seeing the boosted manifold pressure. In these setups, you supply the boost pressure to the fuel tank volume also, instead of venting the tank to the atmosphere. Therefore, the fuel supply sees the same boost in pressure above ambient pressure as the carb. That way, the fuel is still drawn into the air the same as when it was all at atmospheric. This is also nothing new, and it is required of _any_ supercharged engine with a blow-through carb design (car engines, old airplane engines, etc.). Pressurizing the fuel tank on r/c engine setups is also nothing new at all. All of this can be found in any basic book on superchargers (especially older ones, from back when carburetors were still in fashion).
That sonic pulse, or "P" wave travels through the exhaust at approximately 1400 feet per second. The length and diameter of the exhaust tunes that P wave to a certain frequency, which equals an RPM which the engine runs most effectively at. In a two stroke engine this p wave is further effected by the expansion chamber in the exhaust pipe. On 4 stroke automotive engines the opposite of the P wave is the N wave. The N wave travels through the I take manifold and carburetor. Changing the length and size of the intake runners in conjunction with the plenum chamber tunes the RPM range of the intake manifold. When the intake is tuned with the exhaust the most power can be made at the desired RPM.
And the key to the power boost with a tuned pipe is the stopping of the inlet charge so it isn't [partially] lost out the exhaust AND the exhaust charge is fully expelled, hence the need to tune the length.
+Lozzie74 when the P wave leaves the pipe a Negative Pressure or N wave is formed that travel back towards the exhaust valve. If the length is tuned correctly the N wave will help evacuate the cylinder. But this only happens at a given RPM, which is where peak torque should be.
Had a buddy with one. Didn't do a thing for performance. In fact, his engine ran much better after swapping out tuned pipes and crankshafts trying to get this to work, when we once again settled on the stock crank and a well tuned pipe. Saved weight and all this went into the garbage.
how much does the pressure vary depending on the rpm. tuning for low end, vs high end rpm would be difficult no? does that mean it's gonna be PIG rich on the lower side of the rpm range? sick! love the videos too! great job guys!
Mine comes tomorrow. I can’t wait to do a detailed before and after speed run on a radar and also do a detailed break down of the tuning required to maintain proper reps and overall performance. Very excited for this product. My nitro car is the red at shockwave 1/10th scale running a high flow filter, performance manifold as well as the tuned race pipe. So we will see what I get for gains.
+Trev S On RC planes with nitro engines specifically 2 stroke ones the muffler has a baffle inside and there is an output nipple from that chamber which you connect a tube to the fuel tank. What you could do is bleed off air from the supercharger to the fuel tank and that will equalize it with the carburetor air pressure but equal probably isn't enough you need more pressure so maybe a physical pump would be better.
KiwiPowerNZ Thanks for that - We know on motorcycles many early blown engines chose to suck through rather than blow through - looking at the design on this mechanical supercharger which is simple single stage centrifuge running at near engine speed it does not look big enough to impart much pressure - a Dyson cordless cleaner with a similar size spins at 110 thousand revs - are we missing something ? - just curious
As a professional in the field of gas dynamics and thermodynamics of ICEs, the best answer for the question 'How RC Nitro Superchargers Work' is really simple down to they don't. What you were saying is all about how does a two-stroke engine work and has nothing to do with the 'supercharger' what so ever and I highly doubt if the 'supercharger' can create any meaningful pressure at the inlet.
No it stays very evenly tuned once the carb. settings are dialed in to maximum performance. You want to step through the engine tuning process exactly like a normally aspirated engine. Thanks for the question!
We need to see dyno numbers or the theory is just speculation. The dyno doesn't need to be calibrated and perfect. It just needs to be able to show a difference in power levels. A small impeller water pump working against gravity would do it.
Its very possible all that is being done is providing a positive pressure to the carb,this adds power do to the lower draw force required during the intake phase
A tuned exhaust is a far more efficient supercharging device for any crankcase induced 2 stoke. How nitro super chargers work, they don't. If they worked ALL the top RC car guys would use them. They don't.
not an easy thing to research and do endless making of minute changes to pipes and cylinders. I dont have 30 cylinders to just experiment with. some maybe do, mfgrs do, but do they have the time to run thousands! of individual tests? nope. so it CAN work but its so unpractical that itll never really be used seriously.
my name is Peter. .. I want to say that if you had an extra sleeve you could tune the port timing and volume. . grind some material behind the engine cases.. and a bit off the sleeve. allows more volume of air to enter the engine. ..
I see everyone here arguing about boosting a 2 stroke engine.. the problem i see here is not with the fact they are trying to boost a 2 stroke engine, the problem is in the carburetor.. Does it come with a pressurized fuel system? Does it come with a way to add more fuel to compensate for all the additional air? If the supercharger compresses the air like it claims then you would have to pressurize the fuel system at LEAST 1psi MORE than the boost created from the supercharger.. if you don't, you just shove the fuel back into the fuel tank.. Looks to me like this whole setup is a big hoax, unless i missed the part where it came with a fuel pump and a carburetor designed to add fuel to a boosted system..
John Pummill But if your using the "boost" to pressurize the fuel tank its still going to be the same pressure as whats in the intake therefore it becomes a wash, back to square one WITH an EXTRA load (supercharger) on the engine.. the only way i could see this work is if you fed fuel through the supercharger instead of sending "compressed" air through a carburetor designed to work with vacuum.. 2 strokes can be pressurized - there are MANY examples of it being done over the years, but this system is obviously a hoax..
No matter what... if you increase intake gases, it increases exhaust gases which pressurize the fuel tank...the more explosion, the more exhaust gas, therefore pressurizing the tank more (the engine does that while it's running without a supercharger too) if you doubled the intake volume, you'd double the exhaust volume, thus doubling the tank pressure(and assuming the needle could let enough fuel flow) you'd double the exhaust sonic pressure wave that's how guys can run s 300hp 12mil stroker Yamaha banshee with no problems
Detroit's have wet sumps and the boost goes straight from the supercharger to the inlet ports in the cylinder sleeves. They aren't called transfer ports on a Detroit because they aren't transferring the air from the crankcase to the cylinder. Nitro 2-strokes have a rotary valve as part of the crankshaft. Normal petrol 2-strokes have reed valves so as the piston travels down, it can create its own boost to flush out all the exhaust gases hence their inefficiency over a 4-stroke
intake port is open only when exhaust port is open. all boost blows out exhaust. only notice pumping losses from piston comming down in boosted crancase. only turbos work on two strokes.
hi rbinnovations. i'd like to learn about how the carburetor deals with positive pressure. any light you could shed on the subject is much appreciated. thanks
You have something like 140 degrees of piston fighting against the extra crankcase pressure before the transfer ports start to open and then there's the issue of a correct expansion chamber on the exhaust
one thing no one seems to under stand is 2 stroke motors are already supercharged in a way the crank case is a air pump and it sucks thru the carb creating suction for the needle valve it seems like this would just lean out and cook a motor
How does that thin rubber belt stay tight on the engine pulley at 30000+ rpm? The centrifical force applied to it must be crazy, so why doesn't the belt just fly away from the engine pulley and then slip?
I had reservations after some of the comments on other videos. Why not do a side by side comparison of identical cars? One being supercharged and one not. Will I see a "noticeable" difference in my car?
Brilliant video. I don't drive nitro buggies but I fly nitroplanes and I'm a fan of forced induction. Your explanation was spot-on and the graphic demonstration made things clear. Sadly few people understand about the return sonic pulse in a tuned exhaust, which is how they work. Great video!
+John Fitzpatrick thanks for seeking to understand rather than mouthing off like the troglodytes on here. I'm not affiliated with this company and have never bought the product. The rubber band belt looks a bit lean for the duty. However, the science behind the device is sound. They should dyno check it to prove their point - would save the arguing. I hope my response directly to your question was OK.
+DOCK GAMING, you might well be right about the supercharger pressure overcoming the reflect exhaust pulse. Without data it's impossible to know. It's why John Fitzpatrick and I want to see some dyno results - would settle any speculation. As for "your a fucking idiot", I recommend that when tarnishing someone's mental capacity it's best to get your own comment spotless lest you tarnish yourself with the same brush. I don't own any "fucking idiots" so the word you were looking for is "YOU'RE", which is a contraction of YOU ARE. For example, "YOU'RE a keyboard warrior". As for wasting money on a supercharger, let those who pay for them worry about the efficacy of their purchase. Save your beer money for an English writing course, or you risk being perceived as an idiot.
The tuned pipe was meant to “push” back the air/fuel mixture at the stock pressure. With the a/f mixture at a higher pressure, a new tuned pipe needs to be installed that will create enough back pressure to “push” back the higher-than-stock-pressure a/f mixture. Why do you think 2 stroke snowmobile turbo kits come with a new tuned pipe? Because the new pipe creates enough back pressure to keep the forced induction a/f mix in the cylinder. This was a very basic explanation of it because I don’t feel like writing a book on how naturally aspirated 2 strokes and forced induction 2 strokes work
This type of exhaust system on a two stroke is normally known as an expansion chamber. Properly tuned they act almost like a supercharger. Use to set them up for certain rpm ranges to fine tune the engine all the time back when I raced motorcycles. Altitude, air temperature, humidity all affect how the engine is running on a particular day.
Hi to some one to tell me how to get a contact with this company. I order a super charge and still not have a responded from them so please how do I get contact with this people
Installed 1 of these on my tmaxx a while back and did nothing but lean my tune out,and with continuous headaches of chasing tune gave up and it sat for 5years before i just sold it along with ofna picco.26maxx:(
Wouldnt it just lean out forcing air into it? As the levels of air will change through out the range of rpms so you could only really tune it right for up high or down low but then you would risk putting to much fuel and air for when it kicks in? I mean theres no ecu to regulate it
hey um i dont do surface radio control (cars) and i dont wanna feel like im asking this from a whole nother planet but, would it be possible to supercharge a model airplane engine? thanks.
so Im rebuilding a weed eater 31 cc motor and I want to install it on my truck...do you have an super chargers that can be used on an engine this big. willing to pay extra if needed.
you say more fuel delivery will bring temperatures down, what temperatures block temp or combustions temps because if you have a balanced stoic adding more fuel will create more heat ?
richer fuel settings will lower head temps thats not wrong in the RC aircraft world you can run sloppy rich with high nitro fuel in a 4 stroke and they hardly get hot
@@alecw7063 any engine really eg real piston aircraft rich = lower EGT and head temps as you lean the engine EGT and head temps go up till it gets lean of peak then go back down
so this engine has a self ignition, like a diesel engine, am i right? the ignition is timed by reaching a given pressure of the fuel-air mix at a certain angle of the crankshaft. doesn't this system cause a preiginition?
Just wondering that how the sonic pulse from tuned pipe ever hits the goal if that hair drier is on.. i dont say that 2 stroke engines could not be charged, they just need valves..
If it was an open exhaust or standard muffler you would be correct. However, the principle of returning sonic pulse in a tuned exhaust was well understood when I got into tuned pipes in the 1990s.
I know how tuned pipes work, I just say that that leaning machine spoils the only good thing about tuned pipe, the sonic pulse.. I have built engines over 15 years. I also think the ports should be moved so more mixture had a change to burn..
Yes, we have one for that engine, but complete system will depend on the vehicle that your using it on. Email us the vehicle, clutch, and flywheel used along with the engine and we can determine which system works best for you. Our email can be found in the description of this video.
Yes, we have a system for this engine. The vehicle it goes on determines what unit you'll need. Email us your vehicle type and engine, and we can send you a link to the system. You can find our email in the description.
I think he was talking about priming it and it not shutting it off. You should never shut it off by blocking the exhaust. It can force sour exhaust gases and burnt oil into the engine.
If you are building pressure below the piston that would slow it down, thus creating less power. If the Shockwave does in fact do what you say it would only work for the "tuned rpm range" and and power would first have to add back the reduced power from the positive crank case pressure. Any other rpm range where the pressure wave doesn't bounce back at the correct timing would have far less air in the engine but still have all that positive crank case pressure, and would probably actually produce less power. Best case scenario you gain a very small amount at the tuned rpm range and lose power everywhere else across the rpm range, and less power under the curve means a slower vehicle even if the "peak hp" number is higher
Since the supercharger system is creating constant pressure by forcing the air/fuel mixture into the crankcase,and doesn't have to rely on negative pressure to pull the air/fuel mixture into the crankcase wouldn't it be beneficial to increase the intake timing on the crankshaft opening effectively creating more cylinder pressure making the engine think it has an even higher static compression ratio than it already has?.And would also help alleviate the effect of the supercharger on rod to crankshaft pin pressures by forcing more lubrication into the crankcase at the same time acting like raising the oil pressure on a conventional oiling system?
Has anyone tried mounting the carb in front of the supercharger? And also I am not understanding how this is a supercharger in the first place... How can it compress without being exponentially over-run while drawing the air in from the side instead of pulling it in from the center as centrifugal compressors do? My theory is it's just equalizing back to ambient pressure...
The extra intake pressure escapes directly out the exhaust port, since the exhaust port doesn't close until after the transfer ports close. The shockwave bouncing back up the exhaust doesn't have enough force to overcome a *pressurized* intake charge, so the extra intake pressure still escapes and the fuel mixed with it gets wasted. Even if that weren't a problem, your design is still defective because the carburetor is downstream from the blower. That means the pressure generated by the blower prevents the carburetor from generating the partial vacuum necessary to draw in fuel properly, causing the engine to run lean. Enriching the fuel mixture doesn't solve this problem because the pressure buildup at high RPM will obstruct fuel flow even more than it does at low RPM. Furthermore, you say to tune the engine to run at the manufacturer's recommended temperature, which is a good idea, but in this case it also completely defeats the function of the supercharger. Thanks to the laws of thermodynamics, you CANNOT burn more fuel in the same space with the same heatsinking without the engine getting hotter. Tuning the engine to run at the manufacturer's recommended temperature would require running it so rich that it wouldn't produce much, if any, more power than stock. Not to mention tuning it richer will cause *even more* fuel to be wasted out the exhaust when the exhaust shockwave fails to push all of the intake charge back into the cylinder. You are trying to use fancy terminology to talk over the heads of your customers. Your product is a scam. It always has been and it always will be.
I have seen a Turbo Charged 4 stroke on a RC airplane giving 4lbs boost.I believe 2 strokes have a lot of potental yet.A old Diesal 2 stroke at work has a supercharger and turbo on it & fuel injected of course.Be good to try do away with the crank shaft shut of & just let the supercharger do all the work.Then put a rotating exaust valve on to close of the exaust some to let the supercharger ad some more boost.Bit like a CR250 2 stroke uses to ad more bottom end grunt.Wow,Mite try this myself.
Superchargers and turbochargers typically do NOT increase efficiency, as stated in the video, but they do increase power by forcing more fuel and air into the combustion chamber.
