S2E16: We deactivate cylinders on our Saturn and test the car for performance and MPG

well there you have it that's a two-cylinder 950 cc saturn engine that doesn't even make any sense yeah i get it it still looks like a four-cylinder engine and if you count the spark plugs let's see one two three and four so it's technically still a four-cylinder but in this case we've deactivated two of the cylinders and now well we're calling it a two-cylinder engine welcome back to robot cantina today we're going to ask that you pay attention and perhaps drink that extra cup of coffee we have all sorts of shenanigans in store for you and we go way beyond what we indicate in the title and thumbnail today's experiments will be cylinder deactivation and let's see how far we can take this concept so this video was suggested by one of our viewers and it's an interesting experiment to see how much power we can lose and if the car will still be drivable we'll also check the fuel economy and find out if it's possible to save a little on gasoline cylinder deactivation is something that's done on modern larger engines and it's been around since the early 80s when cadillac tried it unsuccessfully of course cylinder deactivation or sometimes called variable displacement is done automatically as the car is driven for today's experiment we will mechanically deactivate the cylinder and it will stay deactivated throughout the test and that's because it's impossible to build an active variable displacement engine on a youtube budget so the theory is the deactivated cylinders will no longer be able to draw in and compress air and this will remove a lot of drag on the engine but it's not perfect and there'll still be some losses but this is more or less how it's done on real systems except they activate and deactivate automatically i have some concerns about my methods and we're going to test this concept out on our parts car before we try it on the good car now our parts car has problems of its own the main problem of course is the fuel pump doesn't work well that sucks but we were able to get the car running with a lawnmower carburetor and if you watched our previous video we tested the lawnmower carburetor on the good car as well now this is interesting by reading the comments on the previous video some folks claimed that i copied thunderhead289 and i absolutely did i gave luke credit for the idea but you wouldn't know it from some of the comments anyway today we're going to do something different and we'll first try it out on the parts car that still has a carburetor on it however if this concept works we'll test it out on the good car that has a functioning fuel injection system the first experiment we're going to try is to mechanically deactivate two cylinders and see if the engine will even run and to see if we still have oil pressure so to mechanically deactivate two of the cylinders we'll need to remove four rocker arms and four hydraulic lifters and we'll need to plug the lifter holes so we don't lose too much oil pressure of course if this engine had a working fuel injection system we'd also need to disconnect the fuel injectors [Music] this guide plate keeps the lifters oriented correctly without this plate the rollers on the lifters would destroy the camshaft and the cylinder head pretty quickly so this is one of the hydraulic lifters and i'm not sure if it matters but we noted the direction of the oil feed holes so we can put the engine back together correctly when we finish the experiment and of course this is the roller which rides directly on the camshaft for now we'll put the lifter back in the engine we will eventually need to pull out these four lifters but first i want to temporarily store the lifters so we can put everything back together the way we found it it's important not to mix up the parts because they've sort of worn into place and even though the parts are interchangeable mixing them can accelerate the engine wear after we put the engine back together a common solution to keep the parts in order is to poke them through a piece of cardboard it's free and it's simple now this last lifter will use this to engineer a 3d model so we can print something to fill the lifter cavity with and that's how we can maintain oil pressure in the engine you see without the hydraulic lifters in place there'd be a massive oil leak inside the engine and would likely destroy the engine so that's the lifter plug we printed these one at a time because the 3d printer was having problems due to how hot it was in the studio we now need to print some caps to hold these in place for this print we'll print all four caps at once now all the parts are printed in abs plastic and this stuff can handle the temperatures we expect to see inside the engine so this is the finished lifter plug we designed it with o-rings to help keep the oil feeds sealed of course this is just a plug and won't ride on the cam shaft overall came out perfect so now we can install the lifter plugs into the guide plate with a few stainless steel screws we printed the plugs with holes just big enough for the screws to self-tap into the plastic oh [Music] now before we can put the engine back together we need to remove the rocker arms off camera i marked the rocker arm so we can put them back in the same location later these rocker arms have needle bearings that get lubricated from oil splashing around and they don't have a direct oil feed so now we can reassemble the engine [Music] let's see if the engine will still run [Music] right away i can detect the engines a little bit sluggish but it's running so we deactivated cylinder two and three and this will allow the engine to be semi-balanced and judging by the idle it seems like this is fairly smooth so so let's do a quick test around the yard now keep in mind this is our parts car the fuel tank for the carburetor is loosely balanced on the roof of the car oh yeah the car also has a screwed up automatic transmission that's stuck in third or fourth gear although reverse seems to work fine now believe it or not this car is completely floored let's see how fast this thing will go at full throttle yeah it's not fast but like i said it's stuck in third or fourth gear now off camera we ran the engine for well over an hour and nothing bad happened so let's do a review it runs it has oil pressure i reckon we need to transfer this system to the good saturn and do some road testing these rocker cover bolts are actually shoulder bolts and it's okay to use the impact driver on them normally you don't want to use power tools to install the rocker cover off camera we disconnected the fuel injectors for the two deactivated cylinders let's see if it runs [Music] well not too bad the electronic fuel injection seems to be cooperating but no doubt there will be codes meh that's par for the course [Music] i'm pretty excited to take this hooptie out for a ride it'll be interesting to see how it performs [Applause] around town at low speeds the performance is noticeably off a bit but the car is drivable the exhaust note is a lot louder and raspier too hmm so the car cruises okay but you do have to keep your foot on the accelerator let's see how long it takes to get this car up to 60 miles per hour [Music] um after the 0-60 test we topped off the fuel tank and took the car out for a ride we managed to put down 162 miles with the two-cylinder engine and that should be enough to accurately calculate the fuel economy so with two cylinders deactivated meh you really have to keep your foot on the accelerator so as not to impede the flow of traffic of course we got a check engine light so let's see what the complaint is well we got a po404 that's indicating that there's something wrong with the egr system on saturn's that's actually a common code it may be related to our experiment and it may not for now i think we'll be okay the next code is the po300 well the ecu has detected a random misfire i got news for you buddy it's not random anyway this code is directly related to our experiment and we can ignore it however normally a misfire code should be investigated right away let's see how this engine runs with three cylinders active and one cylinder deactivated so [Music] oh restoring cylinder number two for a total of three active cylinders well the idle's a little choppy and we have a minor lifter tick [Music] the good news is the lifter tick is normal and that should go away after a while i'm really not sure why the engine burned a little bit of oil on startup but that went away after the engine warmed up so now we have a 1425 cc three cylinder engine with the number three cylinder deactivated let's go out for a ride [Music] i have to say with the three-cylinder version it has more power but the engine also sounds terrible also it's a bit finicky on what gear you put the transmission in for instance at 50 miles per hour in fourth gear the engine will start bucking at part throttle now keep in mind three cylinder engines are a lot more common these days and this of course is a four cylinder engine with one cylinder deactivated the firing order and the balancing is not ideal in our experiment but this is what it is let's see how fast this can accelerate to 60 miles per hour [Music] after the acceleration run we topped off the fuel tank and took the car out for a fuel economy test driving this car with three cylinders is annoying to say the least i'm not sure if it's the sound or the vibrations but it wasn't a pleasant ride we managed to put down 140 miles with only three cylinders operating the extra power was greatly appreciated but the vibrations made it a very miserable ride i was glad to return to the studio now let's see what else we can do to this car so i know what you're thinking why not try running the engine on one cylinder ah sure why not how bad could it be off camera we disconnected the fuel injectors [Applause] wow it started i was sort of hoping it wouldn't run well i reckon we need to take it out for a ride [Applause] [Music] so with one cylinder active this car is a real slug now there's a huge delay with throttle input as the engine has to wind up and that makes sense with all the rotational mass hanging on the crankshaft just for giggles let's see how fast we can get this thing to accelerate with a 475 cc one cylinder engine [Music] [Music] [Music] well well there you have it this car is officially slower than our street legal go-kart i'm not even sure it'll get to 60 miles per hour top speed turns out to be 51 miles per hour but there was something odd going on with the engine i'm not sure if the ecu was having trouble sorting stuff out but the engine would lose power at wide open throttle and ran best at 80 percent throttle these sort of things can happen when you do stupid stuff and we like to do stupid stuff well unfortunately this car is not drivable with one cylinder i mean it moves you can clearly see that in a video and on the back roads it'll pick up speed eventually but there's no way i'm going to drive this thing anywhere but back to the studio then we can review the data including fuel consumption so we make all sorts of videos and i do get comments from time to time and they sometimes ask what is the purpose of the video well this video has two goals the first goal is to evaluate performance when a cylinder is deactivated the second goal is to see if deactivating a cylinder will improve fuel economy now raise your hand if you thought deactivating a cylinder would improve performance anyone oh i see someone back there i think he's scratching his head yeah he is oh okay well let's take a look at the performance results first so this car tips to scale at 2100 pounds plus the driver and fuel now i do have to qualify these results this is data that we collected at the hillbilly proving grounds and your results may vary with all four cylinders active the 1900 cc engine makes approximately 100 horsepower at 5500 rpm now this engine is a bit tired and i'd be surprised if it made 85 horsepower on a good day anyway with all four cylinders active we got the car up to 60 miles per hour in 13.96 seconds and that was done in the previous video of course some of you folks noticed that during that run i shift the transmission rather slow and yeah that's true the problem was and still is the clutch on this car is dragging and it doesn't disengage fully unless you absolutely smash your foot way down on the floorboard and then it still drags a little bit anyway that affects performance no doubt now when we deactivated one cylinder and reduce the engine displacement to 1425 cc we got the car up to 60 miles per hour in 22.96 seconds so that's about nine seconds slower it's hard to say how much power we lost but i'm gonna guess that the engine was making something like 50 to 60 horsepower so deactivating two cylinders reduced the engine displacement to 950 cc's and aside from the lack of power the two cylinder ran better than the three cylinder it's crazy anyway with only two cylinders we got the car up to 60 miles per hour in 34.54 seconds that's 20 seconds slower than the four-cylinder engine and 11 seconds slower than the three cylinder i estimate with only two active cylinders the engine was making something like 25 to 30 horsepower and again that's just a guess now with three cylinders deactivated well it turns out that 60 miles per hour is not achievable i'm not really sure if the ecu freaked out but the engine wouldn't make any power at wide open throttle i had to pull back on the accelerator to gain more speed anyway top speed was 51 miles per hour however we like round numbers so 0 to 50 well that took almost 2 minutes and 11 seconds so that's very interesting now let's take a look at the fuel economy with all four cylinders active the little red saturn eked out 42 miles per gallon with all expressway driving the speeds ranged from 65 to 70 miles per hour now unfortunately it was deemed unsafe to drive the modified saturn on the expressway so we generated a new route let's take a look so this is a 30 mile loop that's pretty much out in the middle of nowhere kansas now keep in mind we didn't hyper mile the car we drove it with purpose and what i mean to say by that is we drove it like a normal person would we didn't beat on it but at the same time we didn't do any tricks to improve the mileage we didn't stick to this route 100 and a few times we missed our turns here and there you know everything kind of looks the same out in the middle of nowhere kansas overall the car wasn't pushed too hard on this route though so with three active cylinders we drove a total of 140 miserable miles and netted 40.01 miles to the gallon interesting now with two cylinders active the ride was more pleasant even though we had less power on tap anyway we put down 162 miles and achieved 41 miles to the gallon oh yeah the one cylinder saturn meh we'll never know i can almost guarantee you the results would not have been good case closed on that one so this was an interesting experiment and of course there's a lot to consider i'm fascinated with the results from the two cylinder engine i mean the performance sucked and that's a no-brainer but the fuel economy surprised me i really didn't think it would do so well anyway fuel economy is important and i'm certain some drivers could have squeezed out a bit more from this car but here's my problem with that i drove the car like a normal person would and i'm reporting real world results now it's certainly possible to do all sorts of hyper mileing tricks and squeeze out better fuel economy but that's not realistic i'm going to say yup there's room for improvement but it's limited to the folks who do that sort of thing for the rest of us well it was just a fun experiment next time on this channel we're going to copy the two-stage lean burn system that was used on the iconic honda insight and implement it on the saturn it should be an interesting experiment to say the least i'm really looking forward to doing this and i hope you folks come back and join us now is the time to consider subscribing if you would click on the like button it really helps us out of course if you have a comment feel free to post it well i reckon i have to put this back together now now what that's stupid it'll never work all right [Music] [Applause] [Music] i'll be damned it does work [Music]

Channel: Robot Cantina

Views: 184,300

Keywords: $99, 212 cc, 420 cc, 420 hemi, alternative transportation, custom, cvt transmission, diy, documentary, efi, electric car, electric vehicle, engine mods, engine swap, fabricate, fuel economy, fun, funny, go cart, megasquirt, gocart, gokart, NO2C, goonzquad, great idea, gx390, hack, hand made, harbor freight, hemi, hho, high performance, home made, homemade, hp, hybrid, lada, lawn mower, lawnmower, modification, modify, motor, motor swap, motorcycle, mpg, predator powered car, Fuel injection, speeduino

Id: aw_85uXlOgc

Length: 28min 52sec (1732 seconds)

Published: Sun Jul 17 2022