Videos about the Wagon - • The Wagon! Alan Building his SMX the First Time - • I Let The Customer Bui... SME Merch! www.stevemorrisengines.com To Become a Channel Member - / stevemorrisracing
What we know: The SMX puts out up to 4000 horpsepower, with the exhaust gasses leaving through 2 tips of Ø 5 inch each. Let's assume race gas and an AFR of 12:1. For fuel per horsepower I find a value online of 142 lbs/hour for 300 hp, so for 4000 horsepower you would need about 1900 lb/hr. With the assumed air-fuel ratio of 12:1 you get a total mass flow through the exhaust system of 24600 lb/hr, or about 3 kg/sec in metric. This is the mass of the air plus the mass of the now burned fuel. Thrust (in Newtons) = mass flow (in kg/sec) times exhaust speed (in m/sec). We have the mass flow estimate but the exhaust speed is more difficult to estimate. We have the total cross section of the exhaust system but we do not have the density of the exhaust gas. As an educated guess: the energy in the fuel will be one third mechanical power, one third heating of the engine and one third heating of the exhaust gas, so an equivalent of 4000 horsepower (2.94 megawatt) will heat the 3.011 kg/sec exhaust gas. Heating a kg of air and raising it 1 °C will take 1.87 kilowatt, so 2.94 megawatt to 3.011 kg/sec means the temperature goes up just over 500 °C. At this temperature the density of air is 0.4565 kg/m³. Give or take some. We also assume that exhaust gas is approximately the same. 3.011 kg/sec, at 0.4565 kg/m³, means that 6.6 m³ is exiting every second. That's roughly 14000 cfm in Imperial. To get 3.29 m³ per second through a single Ø 5" exhaust means you have to have an exhaust gas speed of 260 m/sec. That means a single exhaust tip has a thrust of 780 N. (3.011*259.71=782). *IF all of the above is based on correct assumptions* then two 5" diameter exhaust tips, when spewing out 4000 hp worth of exhaust gasses, *could generate 350 lbf of thrust.*
@@InKind777 You mean it's partially _countered_ by the gyroscopic forces? Sure, the rotating assembly will try to oppose the car from rotating. But the mass of the rotating assembly and its rotation speed are far from sufficient to stop the nose of the car from lifting. (If that was true, no car would need wheelie bars.)
I guesstimated it to about 300 lbf on the last video so the ballpark seems to be there. But the wastegate tubes must have the same direction, or the head will explode in approximations :-)
Nice, pretty close to the total flow volume that I calculated aswell, got a bit higher tho based on guesstimated inefficiencies etc! On the 2-step if the total airmass is close to the proximity of 1200hp as mentioned in the previous video(probably a bit less as actual air flow/airmass increases with RPM). The total volume at 5200rpm would roughly be around 2132 liters per second(75ft³/sec or 2.13 m3/sec) of expanded air. Not accounting for the partially combusted mixture during the 2-step sequence and with the assumption that EGT rises past 650 Celcius(volume expansion over 3 times the room temperature) as the heat is moved out from the combustion chambers closer to the exhaust manifold and into the turbine wheel. Quite a big difference in exhaust gas velocity and volume, should be within 60-75 m/sec velocity for each 5'' pipe. Simply not enough to create any measurable thrust in relation to such a large mass and in the open athmosphere.
Saw Steve, this morning. In his wagon, passing Sherman on seaway dr. Around 6:15 am. It was so cool, seeing a local hero, on his way to work. Doing the grind!! And doing it every day!! Thank you Steve !!
Steve, going off my knowledge with turbines, where the intake draws air from also will play into the force/thrust. You are moving air, and where you take the air from and where you push the air out all have an effect. If your drawing from the top of the car and pushing air from the top of the car, you are essentially canceling out any effects of thrust.
I was about to say the same thing, although you have to take into consideration the added volume of burnt fuel which was compressed, this would result in a greater volume from the exhaust than what is being drawn in by the intake. however you're essentially correct.
@@bigduphusaj162 @dazg258 @Carries338Lapua; Clearly each of You have Your ideas, experience, but lack the actual physics principles. See actual thrust measurements within turbine, jet, rocket engines -> thrust is the amount of force via air flow, pressure - Simple = proper physics [those that actaully studied, learned, know, use physics as physicist, engineers (am among them)] @Steve Morris; @SteveMorris; @stevemorris; @Steve Morris Engines; @SteveMorrisEngines; @stevemorrisengines; Actually Steve's attempted claim with measuring force, thrust with the bullhorns pointed downward on the ground as greater, different than in the open air is certainly false; if anything the proximity to the floor has some affect to reduce the air flow, thrust, pressure; not the opposite as he stated -> proof within every turbine, jet, rocket engine, thrust, pressure output => open air has more thrust, not less; perhaps Your design engineer, local physicist professor will assist Your with the comprehension, understanding of the physics principles too ? All The Best, Sincerely
Engine displacement x Boost Pressure (in bar absolute) x RPM / 2 = Volumetric flow Volumetric Flow / Cross Sectional Area of the exhaust = Exhaust Velocity. Air Density (Exhaust Gas Density) x Volumetric Flow Rate = Mass Flow Rate Thrust = Mass Flow Rate x Exhaust Velocity Something like that anyway, the rounded numbers I used suggest only a few pounds of thrust based on the parameters from the last video. It would obviously be more at full load/full boost etc. but the killer here as others have suggested is probably the cross-sectional area of the exhausts. The exhaust velocity is "low" because the pipes are so big, the garden hose analogy is correct, smaller diameter pipes would produce more thrust but I don't think we're going to see huge numbers.
As an expert RU-vid watcher I can say that the velocity vector of the accelerator combalutator will effect the downward inertia, therefore if you have thrust generator pointed at an opposing fulcrum will benefit your vector of velocity. 👌🏻
Engine displacement x Boost Pressure (in bar absolute) x RPM / 2 = Volumetric flow Volumetric Flow / Cross Sectional Area of the exhaust = Exhaust Velocity. Air Density (Exhaust Gas Density) x Volumetric Flow Rate = Mass Flow Rate Thrust = Mass Flow Rate x Exhaust Velocity Something like that anyway, the rounded numbers I used suggest only a few pounds of thrust based on the parameters from the last video. It would obviously be more at full load/full boost etc. but the killer here as others have suggested is probably the cross-sectional area of the exhausts. The exhaust velocity is "low" because the pipes are so big, the garden hose analogy is correct, smaller diameter pipes would produce more thrust but I don't think we're going to see huge numbers.
People are idiots… thank you sir for all the info and knowledge you lead us to every video. Your videos have actually helped my step son and I to get closer and give us something to talk about as his Grandpas own a machine shop he helps at. So he knows more about the internals then I do. Until now!!!! Haha thank you to you and your boy again!
Steve, I think you'll find it interesting that I drive a 2023 F650 Super DUTY Ford box truck. It's a 26' box. It has the 7.3L gas "Godzilla" engine. I usually have between 1500lbs-5000lbs of payload on it, and it AVERAGES 6.4 MPG. The wagon gets better fuel mileage than my work truck!
Steve, First a couple of comments regarding Hydrazine1000 post: Steve's SMX engines run on methanol which has a stoichiometric AF of around 6.6 and because Steve runs lots of boost I would think that he may run as low as an AF as 3 or even lower, next the energy value of the fuel is not considered in the thrust equation, which is: Thrust=(mass flow)(gas velocity), if you use metric dimensions then the result is in Newtons which can easily be converted to pounds. I estimated the mass flow to be the mass of air at 9000 rpm and 45 lbs of boost and the mass of the fuel based upon the engine running at a Brake Specific of around 1.3 pounds/horsepower hour. This gave me a mass flow rate of 8.4 lbs/sec (3.82 kg/sec) . Using a gas velocity of 100 m/sec gives a thrust of 382 Newtons which converts to about 86 lbs of thrust. The real challenge is to actually know what the true exhaust gas velocity is and my gut feel is that it is certainly probably higher than 100 m/sec. To get higher velocity the exhaust diameter must be reduced, if you reduced the area by 50% (approx a 3.5 inch dia pipe) you would double the thrust but of course you would also have increased back pressure on the turbo. Everything is a trade off! Your testing set up has a couple of problems as I see it: The scales are slow and the electronics that send the load cell signal to the display and the display itself are to slow to give you an accurate thrust reading. It needs to be displayed as a graph just like your dynos along with programing to provide a smooth curve. You might also get a better signal if you put the car on jack stands and the jack stands on the scales, this would eliminate all of the compliance provided by the tires and suspension. Rex
I am very happy that I do not have a garage, if I did I would not have a retirement. I live and work in Atlanta but grew up just north of your shop. Went into the military and moved back for 3 years with my family. My son and I met you at Bristol and he is now a Steve fan, and watches every video that comes out. He calls me and says you need to see this one or that one. Thank you for great information and motivation. I am thankful I do not have a garage.
I love that you care about the shop floor staying clean.. Looks so nice and professional in your shop.. Currently I’m scrubbing down the garage floors, I’d love to get them in nice shape. I could use a fab booth or something, it’s hard to keep the garage clean.
Point the horns toward the back, thrust might get you to that 5.90 😊 Love this channel and content. So great to see people hitting it and earning the rewards.
Always love your explanation videos. No hype. No bad mouthing other people or products. You explain what works and what doesn't and why. Explaining everything to us as equals. Showing the rebuild and saying something as simple as it only needs a new set of rings and put it back together. So many top classes would never make videos like this showing us their "secrets"
put car on a plank, with a round bar at the front-back ballance point. put scales under the front wheels, move pivot till it says something measurable but low, like 1-10 lbs (so theres no slop in system) , then run and see the added downforce pressure
You have some great friends Steve. Allen and Clark working for you for free. During this engine rebuild let's not forget that you made him remove your wagon's transmission in the snowstorm, in a dark cold shop on his back. That is a friend indeed.
Bernoulli's principle. The exhaust pressure is absorbed by the turbos, therefore the exhaust has insignificant energy (pressure or velocity) for downforce. In supercharged applications the exhaust has significant energy remaining for downforce. At 1200hp on the 2-step, exhaust flow on methanol at 2.0 bscf, is 40 pounds of fuel per minute, including the air at 5:1 is 5 pounds air plus 1 pound fuel or 240 pounds exhaust per minute. Calculating thrust would require exhaust area and velocity plus pressure, but if the turbos absorb the pressure and velocity, the 240 pounds of exhaust gas per minute won’t offer thrust/downforce. I hope this helps.
Obviously the scales aren’t lying. Minimal downforce is being created at the exhaust outlets, probably due to the turbochargers have used most of the latent heat and velocity of the exhaust gas flow. I think it would be better to get those bull horns out of the airflow, to reduce drag, and run them straight back and under the car. As a side note, the racing aircraft (see Rare Bear Racing) gain tremendous speed by eliminating the drag of external cooling air ducting and dumping alcohol through an air to oil cooler to cool engine oil, hence the white smoke/ vapor seen exiting the aircraft when racing.
I think that the 'downforce' you are expecting isnt really there. Sure it will produce some thrust. I just think it will be fairly small. What i want to see, is you put an injector in each exhaust with a combustion chamber and nozzle. Then you can make some thrust. An afterburner of sorts. 😂😂
Engine displacement x Boost Pressure (in bar absolute) x RPM / 2 = Volumetric flow Volumetric Flow / Cross Sectional Area of the exhaust = Exhaust Velocity. Air Density (Exhaust Gas Density) x Volumetric Flow Rate = Mass Flow Rate Thrust = Mass Flow Rate x Exhaust Velocity Something like that anyway, the rounded numbers I used suggest only a few pounds of thrust based on the parameters from the last video. It would obviously be more at full load/full boost etc. but the killer here as others have suggested is probably the cross-sectional area of the exhausts. The exhaust velocity is "low" because the pipes are so big, the garden hose analogy is correct, smaller diameter pipes would produce more thrust but I don't think we're going to see huge numbers.
The reason Dewey likes those towels because some waxes have animal fat in them. Buffing compound for metals like the red, green and white are all loaded with animal fat. My dogs use to go crazy over buffing compound.
Mass flow is your key for the force off the Horns. Think like a rocket. You have mass in the tank converted into hot gas at a given rate and velocity. You also have the inlet air coming in with a certain vector and mass. Calculate the difference between those two vectors and you have your force. (F=R×Ve where R is the mass flow rate in kilograms per second and Ve is the velocity of the exhaust gas in meters per second). Now, measuring exhaust velocity is the hard part, you can probably estimate it using a high speed camera (I bet an iPhone or GoPro is good enough) a little oil in the pipe, and a white background.
Yea, trust is what he needs to measure, and trust is mass flow rate x velocity. T=Mf x V, I bet he can pull exhaust mass flowrate from the Haltech that’s on the car now. Measuring velocity would be a different matter, maybe some kinda trick slow motion thermal camera, I don’t think an IPhone would pull it off.
@@Ammoniummetavanadate any thing that has mass would affect the reading, it’s a simple thought experiment, the styrofoam is a good idea, it certainly has the least mass, I can’t think of anything lighter. The problem is it would probably burn, and if you used a lot of it it would skew the reading. Isn’t there some kind of impeller based velocity meter/sensor he could mount right at the horn exit??
@@martindworak There are definitely dedicated instruments but nothing "worth it" so to speak to buy or rent. You only need a few frames of data to calculate the velocity to a "good enough" level.
I can’t wait to see how that piston coating you showed a while back does for your engines and what it looks like after it’s had runs put on the coating can’t wait buddy his engine looks great thanks for sharing
On the aircraft that run a PT6 turbo prop, the exhaust stacks are pointed backwards. This is because they produce enough thrust to make a difference. Here someone apparently did the math for aircraft. “For example a PT6-114A has a shaft horsepower of 675hp, and exhaust thrust of 124 lbs. Add both together using a formula and they come up with an equivalent shaft horsepower of 725hp.”
My 1st car was a '71 Chevy Caprice Kingswood Estate Stationwagon with a 400 ci (with fake wood side panaling}, got it stuck in alot of washes out here in the desert southwest.
Running a boosted altered big block with a single 98mm and one exhaust to the right. It used to blow the car to the left from half track on (low 7sec) Changed it to a split and faced slightly up and it stopped doing it.
Answer you should talk to cleetus and take the wagon to the wind tunnel if they can tell him how much horsepower it would take to get Leroy to 200mph you would think they would be able to calculate the downforce generated by the bull horns. Good luck Steve and love the vids man!
The thrust produced by a rocket can be calculated with the following equation: T = {\dot m}V_e + (p_e - p_a)A_e. T = thrust. {\dot m} = mass flow rate. V_e = exhaust velocity. p_e = exhaust pressure at nozzle exit. p_a = ambient pressure at nozzle exit. A_e = nozzle exit area.
For a (rough) approximation, use: F=P/A (Force = pressure divided by area), which would be the pressure in the exhaust divided by 19.640 (area of a 5in circle); To be more exact, use Thrust is equal to mass flow rate times velocity; use fuel flow and AFR to calculate exhaust gas mass flow, and an airspeed sensor at tip outlet to get velocity. The addition of a simple DeLaval-style nozzle at the end would make it more efficient at making downforce. Two things to note about top fuelers: 1) the mass flow is a LOT higher because of the sheer amount of nitromethane that goes through them, as they run them around 1:1 for AFR 2) the sheer amount of fuel going through them coupled with the rate that nitro burns at results in quite a bit of fuel combusting inside the exhaust, resulting in each zoomie basically acting like a rocket (since none of that exhaust combustion energy was harnessed to turn the crank, the full amount of that energy is released to act against air molecules as thrust)
This is the most accurate comment so far, I agree with what you've said. I did some calcs myself and only got a few pounds. I'm no expert but here's my thought process. Engine displacement x Boost Pressure (in bar absolute) x RPM / 2 = Volumetric flow Volumetric Flow / Cross Sectional Area of the exhaust = Exhaust Velocity. Air Density (Exhaust Gas Density) x Volumetric Flow Rate = Mass Flow Rate Thrust = Mass Flow Rate x Exhaust Velocity Something like that anyway, the rounded numbers I used suggest only a few pounds of thrust based on the parameters from the last video. It would obviously be more at full load/full boost etc. but the killer here as others have suggested is probably the cross-sectional area of the exhausts. The exhaust velocity is "low" because the pipes are so big, the garden hose analogy is correct, smaller diameter pipes would produce more thrust but I don't think we're going to see huge numbers.
Force equals mass times velocity. If you put a mass flow sensor in the pipe to get the mass and use an anemometer to measure velocity that would give you the force.
You keep calling these engines, really they are man jewelry!!! Really to pretty to be this fast! Unbelievable that the things shine like this! Love it! Go fast!!!😎
Hi Steve, totally enjoy all of your videos, My point is , could you add a strain gauge between the pointy end of the front of the chassis to the floor of the workshop or dyno base . Just like being in a wind tunnel but in reverse. What i'm saying is having a gauge that measures the lift on the front end, so you can tune the rear end for better launches.
Interesting points guys. My opinion is to exit under the car. It would create less dense air under it allowing more ground affect at higher speeds. It’s all old Indy & F1 tech but they made rules on the spot, much like Smokey Unicks efforts. You’re wagon would love it. Might want a diff cooler as well.
The only way to really get a grip on whether the bullhorns help is to measure the front shock compression, rotate the bullhorn, run/measure again, plumb in the gate, run/measure, and go from there. That SMX is such a violent machine, the best we can do is take averages that stem from all of its noise.
about the bullhorns no matter what when u throttle the car the engine wants to lift fighting the downforce the exhaust generates ,to get an accurate calculation strap the front and use a basket to add weight above the bullhorn when on the 2 step you will get to a point where the basket nearly floating,for example if the basket had 50 lbs at float you would be able to calculate the downward force they generate based off of your total float weight
Lokal at calculations for thrust from an outlet. We know that Thrust = Pressure × Area and pressure is force/area. So we substitute pressure in the thrust formula and we get: Thrust= Force/Area*Area. Which simplifies to Thrust = Force
I would be super interested for you to build a motor combined with the "FreeValve" technology. Koenigsegg has their V8 running around 2000HP using the FreeValve system. Just imagine no cam shaft or timing chain, super thin heads using the "FreeValve" in combination with running a dry sump... Man, that would be a tuning power house in a small footprint. Super low center of gravity, extra light on weight, endless tuning capabilities... I'm here for it.
Steve: Think the airflow through. You are missing the obvious. For every pound of air the goes out the bullhorn, a pound of air goes in the intake. If the intake faces up and the bullhorn faces up, they EXACTLY counteract, which matches what you saw on the scales. The intake is sucking the sky, and the exhaust is blowing the sky. If you want the most downforce from the intake and exhaust air, the intake would need to face down and the exhaust face up.
If you put a leaf blower on a wheeled cart you could measure the force produced when it was in the middle of the room vs 6" from the wall. The wall will give it something to push against.
That is very cool to have people be able to want to come an freshen up engine then Steve watching over you checking pretty badass. Thanks for sharing be safe guys
Your remark about the bullhorn downward. As long as its 1/4 of the diameter free above the floor the square of the cilinder(pipe) equals the square of the ring(outside length of the pipe times height) the flow speed will stay the same. Only the friction on diverting the flow will occur.
Steve, I had an idea regarding the downforce from the pipes question - Rocket thrust is measured with a load cell or spring and sometimes a pendulum. Maybe if you extended the pipe with a spring-like flex section before a 90* bend, you could measure the deflection of the flex section under boost and then use a load cell to measure how much force equates to that amount of deflection in the flex section. It would at least give a pretty good ballpark.
Hey Steve… since it’s been in 2 videos now, I thought I would chime in. The amount of air coming out of your exhaust is equal to the amount of air entering the car… So your intakes (that are pointing up) are probably lifting the car up as much as the bullhorns are pushing down. It’s like a leaf blower or a vacuum… if you want to push the car down with the exhaust you can’t be sucking it up with the intakes.
I admire your work. You're definitely a genius when it comes to a combustion engine. I would love to own a SMX they are a complete work of art that has been more than proven. With the Drag Week stuff and the Sick Week events. I think it would make a great combo for me, being that I drive my car about 1500 miles a year and hit a few races when possible. The only difference I would like to do is NA as I definitely don't have the chassis for all the possible hp and torque it makes with twins or procharger. Always nice to dream that's what keeps us pushing forward. Love the content very few videos I watch that I don't learn something. As a fan I can't wait to see the WAGON in the 5's. Thanks for all you do to bring great content and education to us.
downward pressure will be absorbed by the shocks before it show at the tire. put the scales under the front frame somehow and this would show direct correlation of downward pressure
Hi Steve, it seems to me that the pressure exiting the exhaust would be somewhat offset by the intake pressure. From what I can tell, the piping to your NACA ducts would cause the intake pressure direction to be close to opposite of the new bull horn pressure direction with the vehicle stationary.
Steve, take a thread bobbin and a 3x5 card cut in half so you get a 3x2.5 card. Lay the card on the bobbin over the hole, blow through the bobbin, and try to blow the card off by blowing through the hole only. You will find you can't do it. In fact, if you blow hard enough, you can blow straight down and not be able to unstick the card with air. Try it works to explain air speed and air pressure.
Clay millican talks about using the exhaust to increase or decrease downforce on the top fuel car. Maybe talk to over of those guys about the effects of exhaust pressure vs downforce.
Damn!!! You get better mileage than I do with my Toyota Tundra 5.7!!! I feel like I've been ripped off!!!?? You get 4k HP and I get 400 HP!!? Somethings wrong with this picture. If I'm pulling the boat or SxS trailer I get 7mpg on the highway!!
The problem with math is the results are an approximation of the real numbers. A good example of this is the displacement values. In order to make the values equate, we have to add Eigenvalues to the constants and other variables. This takes up the slack. An Eigenvalue is a very tiny number, usually too small to measure. Pi is a great ratio to give you a massive round off error.
I’m sorry I didn’t comment on the last video about the downforce. But I think part of the effect of your car seeming to get lighter is that your crankshaft is acting somewhat like a gyroscope. There’s a lot of fascinating videos out there about gyroscopes.
WW2 they pointed the exhaust stacks backwards on the Merlin and found it actually produces forward thrust On the spitfire at 300mph it produced around 70 horsepower and actually gained 10mph top speed. The exhaust was exiting the engine at 1300mph. Not sure what the smx is
How about using the shock travel sensors. Put a good consistent tune that would run the same numbers every run. Do one run horns flat facing back then do a run horns up Compare the front shock travel between runs
If you enjoy it well great ,Last all steel hinged bumpers .crank type windows and rear windows dont clear wheel tubs .69 Nova stock front crossmenber Steel block BBC x2 2800 lbs .Street trim muffer xr1 Borlla
Put some spring closing diesel exhaust truck caps on the bull horns .But instead of normal springs use a fishing fish weight spring guage .Film the spring guage poundage on a dyno pull .
I enjoy watching your videos Steve,crazy how people criticize, you definitely need to not take serious what is commented,it would drive most nuts! Don’t listen!
Steve youre not wrong. We played around with Zoomie angles as well but we found that the diameter of the headers played a bigger roll. We tried 2-3/4, 2-5/8 and 2-1/2 and landed on 2-1/2. We think it was more about the velocity. We also made 42-48 lbs of boost on the 2-step so that might be comparing apples to oranges.
that heat ending up on the steer tires might not be a good thing.. For downforce yes, for traction not so much and I say this because if you have any form of aerosolized oil in your exhaust, you just made bald tires on ice for steer tires
Unless you reroute exhaust for the driving segment with an adapter. It still might work for the drag strip but I wouldn't put my life on it since I don't drag race.
Thrust is a unit of measure to determine the force. You can measure the thrust using the area and pressure of the exhaust... T=P*A Where T is the thrust (N) P is the pressure (N/m^2) A is the area (m^2) I don't think the pressure is high enough to actually get anything worthwhile.. but if you measure the exhaust gas pressure, you could definitely calculate the thrust
I’m glad you explained about the seating position. I mentioned it before in the comments and many people said about weight and balance. I thought it may have been a safety thing. Thanks Steve 👍👍
Import racers have a hood exit for a reason. It puts downforc on the front tires as they launch and go down the track. Its been shown hiw much difference it makes from a single side exit to it straight out the hood. Single side exit pushes the car to the opposite side it exits from. Front wheel drive cars actually hook better with hood exit. So there is definitely downforce being applied on the front end especially withe thos ginormous 110mm twins.
