So if you have all that added force pushing down on the back of the car, why doesn't the Viper just do a wheelie? (mumbles) Well, there's a bunch of goodies up front that helped create downforce on the front end of the Viper. First, there's a front splitter that sticks out about five inches past the bumper in the front of the car, and it also goes a couple feet into the center of the car. And like the rear end diffuser, there are these vertical strikes - they keep the air confined in that area, it traps the air in, so you don't lose any downforce when you're turning. It's the same reason why the wing has vertical edges on the two sides - it keeps the air right in place.

Adding even more downforce are these little winglets on the front bumper, and they have two purposes - like the rear wing, they help produce downforce, and actually if you look close, they also have vertical edges on the side to keep the air in place. And the second function they have is a thin air flow to help cool the brakes. So moving to the fenders, the ACR has louvers. And the purpose of louvers is to vent high pressure building from under the car.

So what does all this aerobits equate to? Well, it equates to the most downforce in any production car ever built, 800 kilograms, 1700 pounds when it's going to top speed of 177 miles per hour. And the more downforce you make, the better your car grips the track. And the better your car grip on the track, the faster you can take corners, and the fast you take corners, the more track records you set.

Now all that downforce comes with a trade off, and that trade off is drag - it's the force acting opposite to the relative motion of whatever moving object you have. So with the aerobics package, it takes the base Viper with a coefficient of drag a 0.37, and it bumps it up to 0.54. That increase in drag effectively decreases its top speed as well, so you lose 29 miles per hour on the top end.

And what the ACR lost in top speed, it more than made up for it in the corners. And when it was released, it went on a run of destroying track records across the globe. Dodge took the old school beast of a car with some engineering tweaks and turned it into an amazing machine. It sucks it's not around anymore, man. It breaks my friggin heart.

It's one of my favorite cars of all time, and for the money there's no more capable car out there. Hopefully one day they'll make another one, and it'll try to kill you just as hard. Thank you guys so much for watching this episode of Bumper 2 Bumper. If you haven't already, please hit the subscribe button.

Also, we're doing something new, all of us here Donut are gonna be in the comments of all of our videos for the very first hour, so be sure to hit that bell, you'll be notified when we post a new video. We'll be in there responding to your comments. So please come hang out with us, let us know what's going on and it'll notify you when we post new shows and we post new shows every day of the week, Donut every day.

Follow us on Instagram @Donutmedia, follow @Jeremiahburton if you got a Viper ACR, you got any Viper, hit me up show me some pictures of a man's. One of my favorite cars of all time, I had two posters in my room as a kid - I had a Viper, second gen Viper blue with white stripes, and I had a purple Lamborghini Diablo. I'm gonna have both of them one day you just watch.

And by the way, we actually need your help. If you want your car featured on Bumper 2 Bumper, follow us on all our social media platforms, we're gonna be posting some of the cars that we need footage from and future episodes and your car could be featured on the show. So thank you so much for watching. Thank you so much for supporting us. Stay safe out there, bye for now.

WEBVTTKind: captionsLanguage: en(car engine roaring)- The Dodge Viper is like baseballor driving on the right side of the road,is the most American thing ever.So when Dodge shut downproduction on the Viperback in 2017, it hurt man.And I hope I'm wrong when I say this,but it will be the lastAmerican made supercarwith a beaten under the hood,and that hurts even more.But, instead of living in the past, today,I'm gonna pay homage, we'regonna look at America'smost track capableproduction car ever built,the Dodge Viper ACR.So first, we're gonnatalk about that acclaimedpushrod v10 engine.And then we're gonna diveinto some of the incredibleengineering that went intothe aerodynamics of the snake,(mumbles) which helpedit set 13 track recordsall over the world, all whilebeing a quarter of the costof a European supercarbrethren, let's go America.(upbeat music)The Viper has always hadthe reputation as a carthat is trying to kill you.The first one in 1992had an eight liter V10,with no automatic transmission, no AC,no exterior door handles, no windows,no airbags, no analyze brakes.So that gives you a senseof what Dodge was going forwith the Viper.They built a wild horsethat was buff, and mean.And if you could get on and stay on,you could have the time of your life.But watch out 'causethis is gonna buck you upand it's not a matter ofif, it's a matter of when,cue clip of a dude driving oneof these things off a cliff.(car engine roaring)(woman screaming)Now the fifth gen Viper ACRis also definitely stilltrying to kill you.It's still that same wild (beep--) horse,but now it's even tougherand it's even meanerwith that new v10 under the hood.But, this time, Dodge hasalso kindly provided youwith a nice little saddle, toraj a new little buff pony,and that saddle is the aeroand with their powers combined,it is an insane beast that you can gallop,your happy little tush aroundthe tracks all over the world.So let's talk about the horse.Why, and how is this thing so crazy?Now this is the fifth gen Viperand it has things like ABS,an electronic stability controlbecause it's federally mandated,but you can turn thosegadgets off and experiencewhat it's like to control 645 horsepowerout of an aluminumnaturally aspirated V10.So what makes this engine so special?Well, first, it's what'scalled a pushrod engine.And there are two main types of enginesin mass produced vehicles today,you got your overhead cam motors,and you got your pushrod motors,also called overhead valve engines.Now the Viper uses themore simplistic of the twoand that's the pushrod.And I say it's simplisticbecause overhead cam enginesare typically more mechanically complexand are more complicated to operate,and from a production standpoint,they arrived on the scene much later onin the history of American made cars.So let's explain the differencebetween the two enginesstarting with the overhead cam design.Now, we've talked about this a bunch,but in an internal combustion engine,you need a way to get air in,and a way to get exhaust gases out.And a few weeks ago, wetalked about the four cyclesin a four stroke engine usingthe sweet acronym SS BB,suck squeeze, bang blow.Now the piston draws airand fuel into the cylinderthrough the intake valves, squeezes it,a spark plug lights that air fuel mixtureand explosion happens bang, boom,and the piston blows the exhaustgas out the exhaust valves,the process starts all over again.Now the timing of windowsintake and exhaust valves openand close to let air in, andexhaust gas out might seemlike it's magic,but in actuality, it's reallyjust very cleverly engineered,mechanical components at work,and that magical metalpiece whose job it isto control all thattiming is, the camshaft.Now in overhead camengines, you have a camshaftthat sits over the combustionchamber in the cylinder head,with the valves sitting below it,and the camshaft has these avocado shaped,people compared they say pear shapedbut I'm gonna say avocadoshape because I'm cool.Now the camshaft havethese avocado shaped lobeson them called cams,and the camshaft is beingdriven by the crank shaftby either a belt, or chainand that's called the timingbelt, or the timing chain.So when the camshaft rotates,those avocado shaped lobespush down on the valve stems,which caused them to openand that lets freshair in and exhaust out.So what about pushrods engines?♪ Whuu! ♪(upbeat music)well, the difference between a pushrodand a overhead cam motor,is in the location of the camshaft.A pushrod engine has thecamshaft located inside the blockrather than in the head.And in a V engine like in the Viper,it's right between the V,right between the two rows of cylinders.Now it's still connected to the crankshafteither by a chain or by gears,but it operates the valvesin a much different way.So as the camshaft rotates,the lobes push on rods,the rods push the rockers,and the rockers push on the valves.So if both engines do the same thing,they cause valves to openand they just go about itin a different way, while aoverhead cam engines consideredtechnologically better.Well first, is in theplacement of the valves.Now in an overhead cam engine,because you have individual camshafts,operating the intake and exhaust valves,you can position those valvesat their optimal angle,which in turn helps theengine breathe betterand therefore you can make more power.And with a pushrod engine,your intake exhaust valveshave to be inline simply dueto the nature of the layoutof a pushrod engine.Now because you onlyhave a single camshaft,you can't get funky withwhere you position your intakeand exhaust valve.Secondly, overhead camengines can rev higher.Because the motion transferredfrom the cams to the valvesis more direct with fewer moving parts,there's less reciprocatingmass to deal with.Remember, with a pushrod engine,that motion from the cam,has to travel all the wayup the length of the rodto get to the valves.So those extra parts, thatextra mass, is therefore harderto move and it's harderto move them faster.I mean, watch this, when Istand next to this light switch,I can flick it on and off really fast.My finger is in directcontact with the switch.Now if I take a step back,and I try to turn that switchon and off with a broom handle,it is much harder to dothe same task quickly,even if I'm really good at it,like I'm the best damnbroomstick light switch flickerin the entire free world,I will still never be ableto match the speed if my fingerwas directly on the switch.So just so we're clear, thebroomstick is like a pushrodand overhead cam engine is my finger.I don't know if I wasclear enough, I hope I was,I don't want to leave anybody out.So the last advantage Iwanna talk about is that,with overhead cam engines, youcan alter the timing and liftthrough clever ways such as VTech or NVTC.Now, we talked about variable valve timingand our 300ZX episodeshould go back and watch it.But VVT is a way in which you can advance,or retard the timing of the valvesusing a specially designed camshaft.And that is a great feature,because it allows the carto be more fuel efficient,you can produce more power,you can have better throttle response.There's a bunch of goodreasons why you would wantto have that.And then a pushrod engine,you don't have the luxuryof using multiple cams toalter your engine's performanceon the fly, well, unlessyou have a Dodge Viper,as it turns out theengineers over at Dodgegot all VVT jealous, and cameup with their own clever wayof using variable valvetiming in a pushrod engine.And I'm gonna get to that in a second,but first I wanna talkabout the advantagesof pushrod engines in general.I mean, there has to be areason Dodge still uses themand not only Dodge, what aboutChevy with their LS engines,one of the best engines ever made.(car engine roaring)So first and foremost is thesize of a pushrod engine,they are smaller than overhead cam engine.A single camshaft placedin the center of your V,means you have smaller cylinder heads,and smaller heads, mean asmaller overall engine packageand that is great on two fronts.For one, when you don'thave big cam sitting on topof your engine, you havemore space to work withwhen designing your engine placement.Take the 300ZX for example,that car is (beep--) to work onand that's because it's got four (mumbles)and it's a big motor packedin a tiny, tiny space,people hate working on that car,you can place the enginelower in the chassis,which then lowers the center of gravity.Having a lower center ofgravity, is obviously greatwhen it comes to stability and handling.There's a reason F1 carsare low to the ground,and you want as much massto be as low in the caras you can.And not only that, but the engine itselfhas a lower center of gravity,with the camshaft being in the blockrather than on top of the heads.Secondly pushrod engineshave tons of low end torqueand the reason they have thattorque in the low rev range,is because they usetwo valves per cylinderand more valves mightseem like a better option,but let me explain.At low RPM, the air enteringthe cylinder is more restrictedand then that air speedsup because of that,that sped up air is more turbulentand causes better fuel air mixing.Higher air velocity plusa better fuel air mixturecreates a better boom andthat means more torque.And the ACR, it has a lot of torquethe most in any naturallyaspirated gas engine,in any production car ever built.It's at 600 foot pounds of torque.Just think about that for a second.Think about all the carsthat have been manufacturedin the history of cars.The fifth gen Viper ACR standsat the top of that podiumin that category, that is wild.So while the Viper has loads of torque,what about horsepower?How does that archaicnaturally aspirated pushrod v10get you 645 horsepower in the ACR?Well, we gotta bring ourfavorite donut equationinto the mix, we got more air,plus more fuel equals more power,and we can usually tackle themore air part of the equationby adding turbos, oradding a supercharger,but for Dodge and true Viper fashion,they did it the good old fashioned way.They made it bigger, theykept it naturally aspirated,and they use displacement as their ally.No turbos, no superchargersand when you're not using force induction,you need as much displacement as possible.And the Viper does that byusing 8.4 liters of displacementacross 10 cylinders.So I'm a visual person.So to help explain how muchthat is, I have a bottle here,and it has exactly 840 milliliters in it.That's 0.84 liters.The contents of this bottle will fill uponly one cylinder in the Viper.So imagine this times 10 (mumbles)10 of those, that is alot of air getting pulledinto the combustion chamber.You might be asking, hey,how this is dude have afriggin graduated bottlebecause that's the last placeI worked in a lab, I stole it.(laughing)Don't say don't put that in.(upbeat music)I teased earlier that theViper has its own versionof variable valve timing.But how can a pushrod enginevary the timing of its valves,when it only has One camshaftand what performance benefitdoes that even get you, well,like all good engineering devices,the Vipers camshaft is quite ingenious.Have you ever seen one ofthese types of drawings?(upbeat music)Well that's kind of whatDodge did with their camshaft,it's insane, it useswhat's called a DuoCam,now this Duo single cam system consistsof a solid intake camshaft,within a hollow exhaust camshaftand the solid shaft hasholes for cylindrical pinsfive of them to be exactand when activated,they align with slots inthe hollow outer shaft.The two camshafts, then become oneand the exhaust timing is altered.So why would you want this?Well the camshaft inthe Viper is considereda performance camshaft,normally this type of camshaftwould be illegal in a production car.Now performance camshaft isthere for one sole purposeand that is to increase performance.(mumbles)But it also increases emissions'cause you're basicallyjust sitting there,always churning at full bore.That's why when you hear some muscle cars,they have that low sound, (mumbles)That is a performance cam andit is also almost definitelyalways not meeting emission standards.So when you're trying tobuild a high horsepower,high torque engine thatis also street legal,you have to strike abalance between performanceand emissions regulations.So to combat that problem,the Dodge engineersuse their new DuoCamcamshaft to reduce the amountof exhaust gas dilution at lower RPMs,making the Viper a more Eco friendly car,and the Viper was the firstproduction pushrod enginewith VVT on the exhaustvalves, pretty nifty.So that was the firstpart of the equation.The Wild (beep--) beaten horseyou got bitwixe your thighs,but how do you keep a carwith such an insane engineon the road?Well, in the past withthe Viper, you didn't,the car was in a constantstate of trying to kill you.It's what made it so charming.Ted Bundy was a charmer.And don't get me wrong,this ACR Viper stillhas the genetic makeupto put you six foot under.But at least the engineersover at Dodge give you a bunchof aero so that when you start going fast,the less angry the Viper is at you.Now the second half that makesthe Viper ACR the best carto ever come out of the USA,is its ability to stick to the ground.We're talking about downforce.(engine car roaring)Better understand downforce,I'll start by explaining lift.Now with a plane youhave a wing like this,and as it goes along, youhave air that pushes up on itand it causes it to lift.Now if we flip that wings upside down,the reverse happens and nowinstead of the air pushing up,it pushes down, andthat is called downforceor negative lift.And in the car world we use a spoileror rear wing to do that, andin the case of the Viper ACR,they use a very big spoiler, a1776 millimeter wide spoiler.Yep, you heard it right,1776 the same year the USAwas founded because of course,this is the best car toever be built in America.I'm trying to tell you guysthis, I'm preaching it.I'm preaching the gospel, youwill be my flock of sheep.I'm the Dodge Jesus (laughing).And that's the size of thestandard wing on the ACR.If you get the extreme aero package,it widens it by another 100millimeters to 1886 millimeters.That's six foot two inches.I'm six foot four inches,that's only two inches shorter than me,just laying there on the wings,it's getting air blasted down, wild man,even the material thewing uses is special.And while most wings havesome sort of structure coreto support it, the ACS wing is hollowand it uses only fourlayers of carbon fiber,but it's still amazingly strong.And there's even structuralsupport built into the trunkto help support all thatdownforce created by this wing.A full grown (beep--) man could standon the end of this wingand it wouldn't break.That is a really strongspoiler and trust me,that's the kind of school you wantwhen you do a really dumb stuff like this.(car engine roaring)That dude for sure lost his teeth,like he doesn't have teeth right now,like homeboy is COVID up withno teeth, just gum and food.Homey, what are you doing?Don't ever do that (beep--)is so stupid (laughing).That spoiler creates a ton of downforce,and I actually read afunny story about this.A guy who was towing hisViper behind his truckin an open trailer,was getting two miles pergallon horse fuel economybecause of how much force theViper spoiler was pushing downon the rear end of the trailer,slowing his truck down ashe was towed along the road.That is pretty cool, I mean sucks for him,but pretty interesting.So if you have all thatadded force pushing downon the back of the car,why doesn't the Viper just do a wheelie?(mumbles)Well, there's a bunch of goodies up frontthat helped create downforceon the front end of the Viper.First, there's a frontsplitter that sticks outabout five inches past thebumper in the front of the car,and it also goes a couple feet intowards the center of the car.And like the rear end diffuser,there are these vertical strikesand those vertical strikes,they keep the air confined in that area,it traps the air in, so youdon't lose any downforcewhen you're turning.It's the same reason whythe wing has vertical endson the two sides.It's like a book-end itkeeps the air right in place.Adding even more downforceare these little wingletson the front bumper, andthey have two purposeslike the rear wing, theyhelp produce downforceand actually if you look close,they also have vertical edges on the sideto keep the air in place.And the second functionthey have is a thin airto help cool the brakes.So moving to the fendersthe ACR has louvers.And the purpose of louvers isto vent high pressure buildingfrom under the car.So what does all theseaero bits equate to?Well, it equates to the mostdownforce in any production carever built,800 kilograms, 1700 poundswhen it's going to topspeed of 177 miles per.And the more downforce you make,the better your car grips the track.And the better your car grip track,the faster you can take corners,and the fast you take corners,the more track records you set.(car engine roaring)Now all that downforcecomes with a trade offand that trade off is drag,and now drag is just air resistance.It's the force acting oppositeto the relative motionof whatever moving on object you have.So with the aero package,it takes the bass Viperwith a coefficient of drag a 0.37,and it bumps it up to 0.54.That increase in drag,effectively decreasesits top speed as well,so you lose 29 milesper hour on the top end.And what the ACR lost in topspeed it more than made upfor it in the corners.And when it was released,it went on a run ofdestroying track recordsacross the globe.Dodge took the old school beast of a carwith some engineering turnedit into an amazing machine.It sucks it's not around anymore, man.It breaks my friggin heart.It's one of my favorite cars of all time,and for the money there's nota more capable car out there.Hopefully one day they'll make another oneand it'll try to kill you just as hard.Thank you guys so muchfor watching this episodeof Bumper 2 Bumper.If you haven't already, pleasehit the subscribe button.Also, we're doing something new,all of us here Donut aregonna be in the commentsof all of our videosfor the very first hour,so be sure to hit thatbell, you'll be notifiedwhen we post a new video.We'll be in thereresponding to your comments.So please come hang out withus, let us know what's going onand it'll notify youwhen we post new showsand we post new showsevery day of the week,Donut every day.Follow us on Instagram@Donutmedia, follow @Jeremiahburtonif you got a Viper ACR, you got any Viper,hit me up show me somepictures of a man's.One of my favorite cars of all time,I had two posters in myroom as a kid I had a Viper,second gen Viper blue with white stripes,and I had a purple Lamborghini Diablo.I'm gonna have both of themone day you just watch.And by the way, weactually need your help.If you want your carfeatured on Bumper 2 Bumper,follow us on all oursocial media platforms,we're gonna be posting some of the carsthat we need footagefrom and future episodesand your car could befeatured on the show.So thank you so much for watching.Thank you so much for supporting us.Stay safe out there, bye for now.(car engin roaring)