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This Small Block V4 Engine Could Be The Cure For The Boring Small Engine

Jack Baruth at Road & Track has taken a deep dive into Motus’ small block LS-based V4 engine and the possibilities of such a powertrain—and boy, are the possibilities endless. For the uninitiated, Motus MST was a newly founded motorcycle builder based in Alabama, but the company has since ceased production of the two-wheeled fun machines. However, the company is continuing to produce its American small block V4 engine—a Chevrolet LS-inspired powertrain that could pack a serious punch with a few modifications.

Motus used the engine to power its motorcycle, making either 160 or 180 horsepower and over 120 pound-feet of torque. From the outside, that’s not much to sneeze at; however, thanks to its initial design, Baruth points out that the engine is capable of accepting larger bore and stroke measurements, potentially increasing horsepower to around 220. Baruth takes his thought experiment even further, discussing supercharging and turbocharging, which could allow the powertrain to make 320 hp or more. That’s a lot of punch for an engine that weighs around a spritely 150 pounds in its from-the-factory configuration. 

Active-Fuel-Management-Cutaway

According to Baruth, Motus has quoted the crate version of the small block LS V4 Engine at $10,220, which is a lot of money, even comparable to an LT1 crate V8. However, what you get with the LS V4 engine is a power-dense powertrain with endless possibilities. Baruth has always dreamed of a four-cylinder Corvette, and the LS V4 engine only stokes the flames of such a fantasy. 

While Motus’ American LS V4 engine sounds great, industry-wide adoption of a mass-produced model appears folly. The engine sounds great on paper, but convincing automakers to shove these engines in their newest cars is the difficult part. Some car companies already use a small block V4 engine via cylinder deactivation—giving consumers the combined benefit of improved fuel economy when cruising and V8 horsepower and torque when pushing the car hard. For example, General Motors offers the technology, calling it Active Fuel Management. Right now, the LS V4 engine in production cars is just a dream, even if could make today’s fuel-conscious economy cars more fun to drive. 

Anthony Alaniz was a GM Authority contributor between from 2018 thru 2019.

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Comments

  1. The problem with this engine is… GM already has it. Higher output turbo 3 cylinders are the future of this segment, achieving similar outputs while making the EPA and CARB happy, using the bad math that people won’t just flood the turbo.

    And that’s before you get to the “gambles” of an all-EV future, which we all know just means not investing in new gas engines because gas will stay cheap and the auto makers hope to keep regulators happy by balancing the numbers with, more EVs.

    Reply
    1. Turbos suck. I have 31 sports cars of varying vintage and the turbos are universally boring. Except in high hp engines where the turbo is just overkill that spool up time is simply annoying. My 1988 Fiero GT has 2.8 v6 NA, it puts out 135 hp. My 1993 Toyota MR2 turbo is 200 hp. Although the numbers show the difference, the drive and feel of the NA makes it feel just as fast. The instant-on power of na engines gives joy to my right foot. For you drag racers I won’t argue. Today’s rev limiters let the turbo stay spooled. But for every day light to light hotroding keep your turbo.

      Reply
  2. There have been race engines that have “halved” V8s for years. Some into straight 4s and V4s.

    Reply
  3. From a packing standpoint, a v4 makes a lot of sense. From a marketing standpoint, 4 cylinders are not “cool” and people want something with “turbos” or V8 and other catch phrases, regardless of power sometimes

    Reply
  4. This is nothing new and they work in racing fine.

    The problem is the genuine suffer noise and vibration issues. They also suffered emissions issues.

    The inlines tend to be better balanced and are built to specific size to male them smoother. 2.0 is not just a random number all MFGs use. Now the 4 valves are not there to be sexy. It is because they can clean up emissions.

    Also with so many cars being transverse mount the in-line is easier to fit in a shorter nose.

    Reply
    1. I have to ask how making a 2.0L engine is smoother than a 1.8L or 2.2L engine. I’m not trolling, I’m truly curious about this.

      Reply
      1. The larger the displacement, the rougher a 4 cyl gets. 2.0 is a good size for power and NVH. The larger they get the more they need counter rotating balance shafts which sap power.

        Reply
      2. Yes there are specific size engines that work best wit specific cylinder and v configurations. On a inline 4 a 2 liter has the best harshness dynamic. In a 60 degree V6 3.0 has tested best for harshness.

        Now you can go bigger but it take more added content to tame the engine back.

        Specific cranks also help too.

        Reply
        1. Honda built 90 degree V-4 motorcycle engines in sizes of 500cc to 1300cc for years because they have perfect primary balance and are considered very low vibration engines especially compared to inline engines. The problem was that they were more expensive to build than the inline fours because you needed two heads, two timing chains, and two exhaust headers. So the statement that they suffer from vibration is not true, and neither is the statement that they suffer from emission issues.

          Reply
  5. Nice potential engine swap for Miatas, Corvairs, Subarus.

    Reply
    1. And 718’s…

      I can’t understad why Poor Shhh didn’t use a V4. Aprilia makes one that sounds truly porkographic!

      Reply
  6. America is being sold “down the river” with these engines. Pathetic….a best of 180hp from a ” power-dense powertrain with endless possibilities”, really??? This is a joke…for 10K??? OMG, believe the BS???! Going to FORD as they at least tell the truth. Yep, down vote me now. GM cuts JOBS, claims they will replace them, yet they don’t. Placating BS to pacify the masses. Buy, lap, it up…..suckers. WHY is it that I can get a 10 spd auto in a mustang and NOT a Camaro/Corvette?????? Yes, they were co-developed at the same time! Yes…tell me all your blah, blah, blah of how they won’t “fit”. BS……

    Reply
    1. It’s a motorcycle engine. 180hp is insame for a motorcycle. GM inspired, not designed, and 10k is cheap, dirt cheap for a engine that it’s made individually by hand. Read before you comment lol

      Reply
      1. Maybe YOU need to read before you comment. “quoted the crate version of the small block LS V4 Engine at $10,220, which is a lot of money, even comparable to an LT1 crate V8” An LT1 costs less and price per cylinder and HP is a LOT less. Not to mention a 525hp LS3…This is GM authority and WHEN did GM start building MOTORCYCLES????? Ignorance is bliss, eh??

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        1. GM authority posts about mustangs and rat rods when a GM motor is dropped in. It’s an Ls inspired motor. Lt1’s are Max produced. This is hand made. I did not misread. Not a GM motor, made by hand, GM inspired and you are triggered.

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          1. Keep drinking the Kool-aid Steven. Made by hand?? They’re all made by hand einstein.

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            1. Actually the Motus V4 is balanced and blueprinted, and not only are they hand built, they are poured aluminum one at a time, by hand. Truly built by hand. Your SBC engine won’t rev to over 8000 rpm w/o some balancing after market. By the way, a crate LS 7 engine is over $15,000.

              Reply
              1. Who said anything about an LS7???
                https://www.chevrolet.com/performance/crate-engines/lt376-535

                https://sdparts.com/i-24080943-chevrolet-performance-19355378-lt376-crate-engine-535hp.html?
                $7900 is a whole lot better than $15k
                gclid=Cj0KCQiA9dDwBRC9ARIsABbedBMNBkWVYDgfvD5EIX3GiIfwVlc3BnyiIuboGLIVPtOPReiOELH8MRQaAswXEALw_wcB

                You’re obviously quite ignorant as to what RPM levels can be reached by the 3/4/5 gen SBC with simple valvetrain upgrades as well as the best application for turbo’s.
                Ignorance is bliss for you as well I see.

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              2. Unfortunately, they Motus V4 manufacturer does not respond to emails about purchasing their motors. I doubt seriously they are still building them. I have written to them three times with no response.

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      2. Btw.. I have a ’99 buell with a 101hp v-twin, lol
        Have you never heard of a Boss Hog? An LS in one of those is seriously sick. lol….More than a 180hp V4…

        Reply
        1. And you double the weight, power to weight is the key here.

          Reply
          1. Well, you obviously don’t know bikes. A boss hog doesn’t take a weight penalty like a car does. More motor =’s more power, period. A bike frame does not incur the weight penalties a car does. Do your research and quit being a fanboy.

            Reply
            1. You did read the article right, this is not from GM. It is merely based on GM’s gen 3 V8.

              “Going to FORD as they at least tell the truth”. FOMOCO has been one of the most dishonest car company’s there are, since the beginning!

              Why did Henry Ford step down and put his son Edsel in charge of the company? To cause the shares value to plummet in an attempt to squeeze out his minority shareholders. Henry Ford threatened to set up a competing manufacturer as a way to finally compel his adversaries to sell back their shares to him.

              Especially the Dodge brothers, by cutting off their dividends and forcing them to sell their stake in the company for cents on the dollar. Henry Ford planned to starve the Dodges of capital to stifle their effort to build a rival car company.

              Who invented the assembly line? (it’s not who you think)
              Google
              “The first mass produced car”
              You need more
              “The Battle of the Overpass”
              “Dearborn Independent The International Jew” (which Ford used to force his dealers to sell or give out)

              Have fun with your honest, genuine Ford!

              Reply
              1. Oh hell, here we go again… YES I read the article and my point is, it’s NOTHING remarkable! Take an LS1 and cut it in half and THAT is all you have, regardless of WHO makes it… I don’t own a ford and most likely never will. It was an exasperated point and IF you agree with GM’s job cuts then my point stands. Flame on….

                Reply
                1. So, Lampert or Barra for you?

                  Reply
    2. Gm has the 10spd in the camaros and truck. It cant be used in its current configureation in a corvette as they have a trans axle and the car probably doesnt have enough space due to being designed befor the 10 spd

      Reply
  7. That engine was developed at Katech in Detroit

    Reply
  8. V4 Corvette??? Why??? Pathetic!!! Awful!! IMHO dumb!!! What is Baruth smoking? It must be good stuff. Now if you could take the V4 and add it bolt on to the V8 and make it a V12 Corvette – YEA!!!

    Reply
  9. Give me a v8 4spd heater and key for 8 grand seems fair no options just heat ?

    Reply

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