The Porsche Cayman GT4 Has Dimples Like A Golf Ball!
2021 Porsche 718 Cayman GT4 vs 718 Cayman GTS 4.0 - Aerodynamic Comparison!
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The Porsche Cayman GT4 and GTS 4.0 both feature a naturally aspirated flat-six cylinder engine. They both have PDK and manual transmissions offered. And in this case, they're both the same shade of blue. But there are actually dramatic differences in terms of how these cars perform, much of which might be overlooked by the naked eye. The aerodynamics of the GT4 are all about downforce, while the GTS 4.0 is all about minimizing lift. The GT4 has an upgraded chassis, suspension, wheels, tires, engine tune, and many aerodynamic changes to maximized downforce and minimize drag. Part of the solution? A dimpled underside, similar to that used on a golf ball!

On a golf ball, these little dimples cause turbulence, meaning little pockets of swirling air, so instead of a laminar boundary layer, you have a turbulent boundary layer. In this case, the turbulent boundary layer stays attached to the golf ball longer, wrapping around the ball, meaning the wake behind the golf ball is smaller when the airflow detaches from the golf ball, and a lower pressure region forms. With a smaller wake, the ball has less drag, and thus can travel farther. Porsche says the same logic applies to the GT4, in their words: “At the front end, the special surface on its underside is dimpled, reminiscent of that of a golf ball. As a result, the airflow follows the contour more precisely, reducing drag.”

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  • Zoomer 30
    Zoomer 30

    Make a car where the skin forms dimples as you drive faster.

  • M D
    M D

    Gt4 vs Honda type R ? Specifically on track use and difference in cost consideration. Thank you

  • Grassy Knoll
    Grassy Knoll

    Reject Porsche, return to Supra.

  • josh hightower
    josh hightower

    i still have the plan to get dimples put into a car by a body shop eventually.

  • rodrigo m
    rodrigo m

    liek if you come from Adam Savage' channel

  • mazpr2025

    1992 - Morey Boogie Mach 8-TX

  • sammeo

    So the Mythbusters are right after all.

  • Graham Cranston
    Graham Cranston

    It's called a "frunk"

  • Toby Lundh
    Toby Lundh

    Hi, very good Video and explaninations, thanks a lot for this video:))

  • machfive916

    Maybe in retirement, I can finally get my Porsche.

  • Roger Skagerström
    Roger Skagerström

    Surprised that a track orientet GT4 still doesn't beat an 8 year old Datsun around the Ring - the Porsches home turf ;-) Got to love the new gen Boxster/Caymans though. Wonder how far they can go with crippling the smaller ones to justify the 911's existence.

  • ILykToDoDuhDrifting

    2:25 Already destroyed the under panel. That'll be $10,000

  • Kyle Mcweeny
    Kyle Mcweeny

    I love mobil 1

  • Ibby H.
    Ibby H.

    Is there an application of those dimples in space rocket tech? 🤔

    • Ibby H.
      Ibby H.

      Thanks for the explanation and the new topics to research @zoka Makes sense now why they seem to focus on making smoother surfaces while keeping the same shape.

    • zoka

      No. There are two types of drag 1- Form drag. Which is caused by the difference in pressure between the front and rear of an object. 2- Friction drag. Caused by the friction between the fluid and the object. Depending on the shape of the object, they contribute in differing ratios. After a point, more streamlining increases the drag because the reduction in form drag becomes smaller than the increase in friction drag. Dimples decrease the form drag but increase the friction drag. Air and spacecraft are very streamlined and friction drag already makes the most of the drag on these vehicles. Dimples would increase the drag. Though there may be some very specific cases they may be useful but a wide scale adoption is not going to happen.

  • Stephen Riggs
    Stephen Riggs

    Cool, and all, but I'm much more envious of your Tesla 3.

  • Pootis Spangle
    Pootis Spangle

    The turning on these cars is something America took decades to figure out, but they finally did with the 2022 Chevy Corvette, because it was designed to look and perform like a European supercar, which is way better than any American supercar.

  • karl reisa
    karl reisa

    Porsche Caymans S jaaaaaaa

  • DoxYDox DeLamanca
    DoxYDox DeLamanca

    The golf or dimple bottom, wasn't that used by Lexus in one of their big series LS car back in the day?

  • 나의라임지리는나무

    what a perfect choice


    Still can't ship Tshirts to mylil island :(

  • Shawn D.
    Shawn D.

    The answer to the track question is yes, I do want to track it. I am still not convinced I should be buying the gt4. At a savings of $20k and exactly the same engine (and same performance after an ECU tune), can't I turn the gts into a gt4 on my own and have money and spare parts left over? I would really like your thoughts as I am currently deciding which to buy.

  • Don Lee
    Don Lee

    If manufacturers really did care so much to reduce fuel consumption and be better for the environment, they'd make dimpled panels for all their cars. Obviously, they realise people prioritize looks over their wallets or saving the planet

  • Amaroq Starwind
    Amaroq Starwind

    So... These dimples would reduce drag without reducing underbody downforce? But what about the "dirty air" that other cars have to deal with?

  • thetommantom

    Sometimes it's not just specs or numbers sometimes it's just about getting the best one and not getting something that wasn't done up all the way

  • Wolfgang Himmelsbach
    Wolfgang Himmelsbach

    Or just buy a GTS 4.0 with a PDK if you don‘t like the gearing

  • Victor Martinez
    Victor Martinez

    I’ll take the blue one😼

  • Gregoire S. Blachon
    Gregoire S. Blachon

    Dude we need you on our team to make our Pikes Peak Bug diesel record even better!

  • mry82

    I picked up 5 mpgs after my car sat in a hail storm. Edit: I should have watched this a week ago; my joke was already taken...

  • Martin Warne
    Martin Warne

    You know your a somebody when James May talks about you on Drivetribe

  • fraginz

    So it acts like a vortex generator without actual vortex, and for the boundary layer only. That's nice.


    Just get the base cayman all day

  • Frank Lanois
    Frank Lanois

    I've recently seen race shops use the dimple idea inside intakes and heads to maximize airflow

  • Nico D. Sun
    Nico D. Sun

    Do you visit the racetrack? No. Fiat Panda it is.

  • Jackson Bauerle
    Jackson Bauerle

    The bananas are for us apes we’re going to the moon! And I’m buying gt4 with one of my call options next week. AMC

  • Peter Ruiz
    Peter Ruiz

    Now I have seen everything....

  • clockradio989

    Drove a hail damaged ford fusion for five years. Never proved it was more aerodynamic, but was a fun conversation starter.

  • Rafael

    So today I realised that the dimples from the underside (almost all the underside is covered in these) of my 2006 VW Polo 1.2 are actually there for a good reason, lmao.

  • Eason Y
    Eason Y

    This video makes me remembered that my wife's glc300 also has those dimples on the underbody

  • More Lipstick More Cheap Chicks
    More Lipstick More Cheap Chicks

    Fun fact: a company was looking to make airsoft BBs with dimples to increase their lift and thus their range

  • John Shepard
    John Shepard

    Nice !

  • Otis Driftwood
    Otis Driftwood

    I think if designed correctly a dimpled car could look good. What I'm curious about is if dimpling large areas of the surface of the car would end up making it unstable at high speeds. Otherwise I would have thought we would have seen this in racing by now (especially Le Mans prototype/experimental class). It would seem we should integrate this basic tech into both EV and large trucks made for long distance hauling.

  • Henrik Carlsen
    Henrik Carlsen

    In the early 90'ies I read an article about how the dimpled texture of shark skin produces less drag and that surfboard manufactures were trying to incorporate this to their boards. Never heard more of this but I have always wanted me a board with "shark skin" surface, because I felt it was a good idea.

  • Rick Houston
    Rick Houston

    People be buying up hail damaged vehicles for aero gains

  • roguedogx

    2:54 okay so there was an update to that story that I think you will find interesting. So in one of Adam Savages "tested" Q&A videos, at the end he says ford took one of their clay models and recreated the experiment in a wind tunnel. apparently they replied with a letter that stated "we don't agree with your results". so considering Ford couldn't recreate the results that could indicate why.

  • okleydokley

    This dimpling gimmick was seen in cycling for years to reduce drag by generation of a boundary layer. Or, that was the marketing idea. When tested, it never does anything but generate more drag which is why they don't use it in racing.

  • Jeff Thawn
    Jeff Thawn

    Buy them both. One for your daily. One for your track.

  • Brian Yeung
    Brian Yeung

    this is one of the best and most detail review on GT4 i have ever seen, good work man

  • ollo LoL
    ollo LoL

    Vw jetta impressive

  • Jon Gourley
    Jon Gourley

    what!? no white board? smh

  • Joseph


  • Emmett Dibble
    Emmett Dibble

    Mercedes 219 chassis did the golf ball first.... Just sayin...

  • Hertzair

    Race cars...where appearance isn’t important...should try dimples on the body work...maybe however that would increase lift?

  • SMC

    Excellent material, thanks for uploading.

  • DarkClosetOfTheMind

    I agree the aesthetics would suffer on a car, the BIG question is why don't planes and helicopters use this?????

  • Keith Whitty
    Keith Whitty

    We don't need your simple education on aero thanks. Most know qnd those that don't will as they develop their hobby and wake up from a deep deep sleep.

  • Keith Whitty
    Keith Whitty

    About time, I thought about this as a child.

  • Robin Singh
    Robin Singh

    Hi, as a 992 Carrera S owner, should I trade mine in for a GT4 718 PDK? The reason behind this is the look of the car and the overall sporty feel as I feel the 718 GT4 may be a more fun car. What are your thoughts? Great video and very thoroughly explained btw.

  • Ian Visser
    Ian Visser

    So what you're saying is that Mythbusters was right and the automotive company back then that did testing and said it was bs was wrong? Amazing how literally 10 years down the line they finally realized that they were actually doing real science...

  • Ailios

    Man I want a GT4 so bad.

  • FNS

    As always, very interesting video. I am going to investigate now how exactly a rear diffuser generates downforce, which is something I've never known despite being a mech engineer lol.

  • Nick Wisniewski
    Nick Wisniewski

    A quick thank you to Mobil 1 for sponsoring this Porsche-n of the video?

  • Paul Compton
    Paul Compton

    Not just bananas; organic bananas.

  • sticksabuser

    This video is bananas 🤣

  • x x
    x x

    Can you make a video on Hondas j35z 60° engines and why they destroy every transverse mounted v6s of around the same displacement

  • Beetleything

    Vast majority of GT4s around here. PNW. Don’t the wing to go posing-local coffee and highway top speed 90kms. 🙈🤷‍♂️🤨

  • fluffiestspoon

    The older I get the more I realize how much of an influence Mythbusters had on my now methodical and logical mind.

  • Yan

    conclusion : buy an Alpine A110

  • Otieno

    Lexus utilized a similar system ~20years ago. Puma also used it on ⚽️s

  • MB Taber
    MB Taber

    German license plate, S=Stuttgart.

  • Jake P
    Jake P

    Does Adam, Jaime, and discovery channel get a check for the R&D??? lol

  • Bee Nobu
    Bee Nobu

    The Mythbusters did it first!

  • Brian Hiles
    Brian Hiles

    _Without even having seen the video..._ It´s unlike the competent German engineering team at Porsche, to have indulged in the _engineering du jour_ of golfball dimples. I can think of no place on the body, and relative to the typical flow field thereof, that the aerodynamic principle that makes golfball dimples a practical discovery, makes sense. The high rotational speed of a golfball in flight entrains low-energy air within its boundary layer into said dimples, moving it from where it is to where is should be going anyway, dramatic decreasing induced drag with the incidental effect of increased flight stability. This effect is only dominant when rotational speed is much greater than linear speed. Now I´ll watch the video to see if I´m wrong, but I doubt it.

  • Tips 4 truckers
    Tips 4 truckers

    I knew there couldn't be an ee video without mentioning gear ratios or tires.

  • Simeon o
    Simeon o

    So Porsche watched that Myth Busters episode.

  • vqlvo

    I thought the bugatti only had this feature

  • Zohar Modifier
    Zohar Modifier

    wrong ... Jason ! ... when you buy gts4.0 ... the peers will ask why didn't you get the GT4 ... when you buy GT4 ... they will ask you why didn't you get 911 lol :)

  • Harshith Sadhana
    Harshith Sadhana

    gt2, gt3, gt4, gt3 cup car, carrera s carrera4s, - reminds of JC having a big argument why ferrari was better porsche

  • sdlausen

    Car company: Lets test a car completely covered in dimples Me: Trypophobia intensifies

  • lowtus7

    Did anyone else notice they went to the effort to do the golf ball thing, but then put a janky bit of plastic with exposed screws etc right in the front.

  • Chris Bryant
    Chris Bryant

    The 2005 Ford GT had the dimples on a large area on the under body. It is very cool to see this technology used on vehicles. Enjoyed the video.

  • Zeal of Sparta
    Zeal of Sparta

    I wonder how much downforce the car makes at speeds of 45 to 85 MPH? I hear the top speed figures a lot on different cars but for handling purposes why not list more common speeds?

  • TheRealMrRoboto

    Infinity and others do dimpled underbodies....

  • Cevan42

    My old '09 Passat had dimples on the undertray.

  • Gavin Sullivan
    Gavin Sullivan

    Well I should know better by now of course but that was much better than I was expecting!

  • Dragan Crnogorac
    Dragan Crnogorac

    Dimple car didn't work. It was accidentally more efficient

  • smaug M
    smaug M

    12:22 Banana for scale! That catched me off guard :D

  • TM

    The first time I heard about dimples I immediately thought of cars. This was a long time ago. ;)

  • GabenHood

    Do you think a combustion chamber with golf balls for increased surface area would work? If so, would your theoretical piston also have dimples or matching lumps?

  • Marcfd

    Great video. I can't, however, agree with your conclusion. The GT3 derived front suspension and bespoke rear suspension in the GT4 completely change the handling characteristics of the car, whether it's road or track. They are both great cars but with its upgraded suspension, the GT4 is the better driver's car, track or street.

  • Carlton Schmidt
    Carlton Schmidt

    I'm going to fight you on the gearing complaint. I have a 987.2 that I take to the track and having second gear top out at 70 mph is actually useable. Every other car that I've driven (Focus RS, VOLVO 240) with a 2nd great that tops out at 60 mph is basically worthless to me. even on very tight tracks or tracks with a tight corner

  • Patrick Fargie
    Patrick Fargie

    I've been pondering golf ball aero for the Miata. I guess hitting rock bottom years ago has had a massive benefit 😂

  • Joseph Herbias
    Joseph Herbias

    Is that a GT4 with clubsport package? That roll bar or harness bar is not available stock in the US

  • SquidProQuo

    LOL! OK! To get aerodynamic efficiency the golf ball dimples does not need to be exactly like golf ball dimples. As long as, the surface has enough irregularities to prevent the back of the car to be sucked back by the wake created from the smooth surface of the sheet metal, the purpose would be achieved. So, why did you think that Honda still put "Fake Vents" on the Civic Type R especially at the back? Why do you think that Toyota Supra has so many fake vents around? One brilliant car reviewer makes a comment about fake vents and the rest follow him along like a sheep, together with all the enthusiasts, dying to write a negative comment. LOL!

  • RI Outboards
    RI Outboards

    Would be funny yet tragic if he forgot about those bananas for like a month

  • Patrick O'Donnell
    Patrick O'Donnell

    Excellent! Thank you

  • Wieldop

    This 'Porsch-ion of the video'? No? Anyone? I'll see myself out...

  • Chris Beller
    Chris Beller

    Great video, thanks for the info. I noticed all the downforce data is at top speed. About how much downforce is available on my GT4 at the track, where speed doesn't exceed about 130 MPH? I'm assuming downforce goes up with the cube of speed, so I'm thinking it decreases pretty rapidly coming down from top speed.

  • Talan Pomeroy
    Talan Pomeroy

    Man, that car looks good.

  • Cr Hu
    Cr Hu

    Every car needs underbody panelling.

  • Cr Hu
    Cr Hu

    So...does this affect the optimal speed balancing drag, lift and momentum? For gas vehicles this was about 55mph/90kmh. I wonder if these features make enough difference to change that optimal speed. And is it any different for EVs?