# Why is is so difficult to engineer a car that can go over 200 mph? **URL:** \ **Category:** Factual Questions\ **Created:** [December 6, 2013, 12:36am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623 "2013-12-06T00:36:06Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Saintly\_Loser](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saintly_loser/32/4045_2.png) [@Saintly\_Loser](https://boards.straightdope.com/u/Saintly_Loser)\ **Post date:** [December 6, 2013, 8:24pm UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/41 "2013-12-06T20:24:11Z")
> [@GreasyJack](#): > > Yes they are. Since around 2000, there’s been the so-called [Gentlemen’s Agreement](http://en.wikipedia.org/wiki/List_of_fastest_production_motorcycles) to limit the top speed of superbikes, which all of the big manufacturers have thus far complied with. The last 'busa before the agreement did 194, but with current generation bikes it seems to only take some light modifications (and a light rider) to hit 200. I was going to post about the Suzuki Hayabusa. It’s limited (with a rev limiter) to about 190. You can buy, for relatively small sums of money, electronic devices that will fool the rev limiter and allow the bike to exceed 200 MPH. And the bike lists for less than 15 grand. ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [December 6, 2013, 9:59pm UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/42 "2013-12-06T21:59:44Z")
> [@Saintly\_Loser](#): > > I was going to post about the Suzuki Hayabusa. It’s limited (with a rev limiter) to about 190. You can buy, for relatively small sums of money, electronic devices that will fool the rev limiter and allow the bike to exceed 200 MPH. > > And the bike lists for less than 15 grand. From what I understand, you also have to change sprockets because with the stock gearing the engine hits the redline before 200. It’s also apparently a good idea to tweak the suspension a bit. But between buying it and those light mods, it’s definitely possible to get a 200 MPH bike for less than a nicely-optioned hatchback. Also, the magic number that all the bikes are limited to these days is 300 KPH or about 186 MPH. > [@epbrown01](#): > > I’ve read the current Hayabusa is good for 248mph. It’s always cited as the 2nd fastest bike, after the V10 Tomahawk (350mph). Maybe a highly modified nitro-breathing one, but in their (mostly) stock form it’s a struggle to juuuuust squeak over 200 with a relatively small rider. ---
**Author:** ![Saintly\_Loser](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saintly_loser/32/4045_2.png) [@Saintly\_Loser](https://boards.straightdope.com/u/Saintly_Loser)\ **Post date:** [December 6, 2013, 10:04pm UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/43 "2013-12-06T22:04:12Z")
> [@GreasyJack](#): > > From what I understand, you also have to change sprockets because with the stock gearing the engine hits the redline before 200. It’s also apparently a good idea to tweak the suspension a bit. But between buying it and those light mods, it’s definitely possible to get a 200 MPH bike for less than a nicely-optioned hatchback. > > Also, the magic number that all the bikes are limited to these days is 300 KPH or about 186 MPH. > > Maybe a highly modified nitro-breathing one, but in their (mostly) stock form it’s a struggle to juuuuust squeak over 200 with a relatively small rider. I didn’t know about the sprockets. I don’t recall reading that about the first models, but the ratios may have changed over the years. And yes, I would say it’s a _really_ good idea to tweak the suspension before attempting 200MPH. A nice set of Ohlins shocks, maybe. I would say it’s an even better idea never to try it. It’s hard to imagine that a bike like that can be sold to any 18-year-old who can get his parents to co-sign the loan. ---
**Author:** ![epbrown01](https://avatars.discourse-cdn.com/v4/letter/e/7ba0ec/32.png) [@epbrown01](https://boards.straightdope.com/u/epbrown01)\ **Post date:** [December 6, 2013, 10:43pm UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/44 "2013-12-06T22:43:49Z")
> [@GreasyJack](#): > > Maybe a highly modified nitro-breathing one, but in their (mostly) stock form it’s a struggle to juuuuust squeak over 200 with a relatively small rider. Nope, just the 1300R. It’s on several sites like those below, but I’ll concede I’m dubious - seems like something the mainstream press would mention. 🙂 [![](https://static.cargurus.com/images/site/2008/06/12/15/58/1979_ford_mustang_base-pic-54169.jpeg) ](https://static.cargurus.com/images/site/2008/06/12/15/58/1979_ford_mustang_base-pic-54169.jpeg) [http://www.steelbabes.com/forum/fastest-bike-world-2-suzuki-hayabusa](http://www.steelbabes.com/forum/fastest-bike-world-2-suzuki-hayabusa) ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [December 7, 2013, 1:05am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/45 "2013-12-07T01:05:20Z")
FWIW, although the absolute top speed for straight-line runs is now supersonic, the closed-course record - how fast you can continuously move and return to your starting point- is only about 250 mph. Beyond that there simply isn’t enough traction to take curves, and the G-forces must be like you’re trying to hug the side of a steep hill. ---
**Author:** ![Mr.Goob](https://avatars.discourse-cdn.com/v4/letter/m/c77e96/32.png) [@Mr.Goob](https://boards.straightdope.com/u/Mr.Goob)\ **Post date:** [December 7, 2013, 1:06am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/46 "2013-12-07T01:06:39Z")
I’ve gone about 140 on an an empty stretch of I95 in a car and felt calm and composed. Then I’ve done over 160 according to the speedo on a CBR1000 motorcycle. White knuckle all the way. Yes there was a speed differential to the square of blah blah blah, but the ruthlessness of speed on a bike is so much different. The gut wrenching knowledge that if something goes wrong, you are not going to get hurt. You are going to rag doll down the pavement until you die is so viseral it makes me wonder how I survived my 20’s. Would I love to try a car that does 200? Hell yes, on a bike, no way in Og’s name. That’s it. I’m officially an old man. ---
**Author:** ![Svejk\_1](https://avatars.discourse-cdn.com/v4/letter/s/ea666f/32.png) [@Svejk\_1](https://boards.straightdope.com/u/Svejk_1)\ **Post date:** [December 7, 2013, 1:31am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/47 "2013-12-07T01:31:27Z")
> [@bengangmo](#): > > The first is that it’s a nice round number, so symbolic as much as anything else. Just wanted to point out that for most of the people that design cars like this, 200 mph is around 320 kph and not exactly a round number. ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [December 7, 2013, 2:20am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/48 "2013-12-07T02:20:32Z")
I suspect this has to do with cooling the engines. As someone pointed out earlier, as the speed doubles the engine has to have 8 times the power. Since gasoline engines are typically 25% (higher end) efficient it means for each horsepower generated at the wheel, 3 horsepower (equivalent BTU/hr or Watts) needs to be dissipated off the radiator. So the radiator needs to lose heat at 8 times what it looses at half the velocity (hopefully without adding to drag). Granted the radiator sees a better heat transfer coefficient with the increased air speed - but I will guess the increase in heat transfer characteristics is linear with speed not cube as the power. And attempts to improve heat transfer may increase drag. And the engine will probably have to go to higher speeds for 200 mph (or you’ll need a large transmission) and maybe even less efficient at higher car speeds and thereby needing even more heat removal. ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [December 7, 2013, 2:23am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/49 "2013-12-07T02:23:32Z")
BTW - here is an old chart that shows speed versus engine power. [See page 260 - bottom right hand corner](http://www.inference.phy.cam.ac.uk/sustainable/book/tex/ps/253.326.pdf) ---
**Author:** ![slowlearner](https://avatars.discourse-cdn.com/v4/letter/s/a88e57/32.png) [@slowlearner](https://boards.straightdope.com/u/slowlearner)\ **Post date:** [December 7, 2013, 3:04am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/50 "2013-12-07T03:04:50Z")
I used to work for this guy named Steve who had to drop out of school in 10th grade to feed the family when his dad died. I always helped him with his reports cause he was damn near illiterate, but he’d been building race cars since before he could drive and I was amazed at how easy it is now for all the shade tree mechanical geniuses in rural Texas to get 1000 HP out of an old 60’s Detroit V8 just by buying ‘tech.’ Street racing is too expensive anymore or I bet there’d be all kind old muscle cars bopping around here at 200mph, shades of Tiny Lund. ---
**Author:** ![Kevbo](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@Kevbo](https://boards.straightdope.com/u/Kevbo)\ **Post date:** [December 7, 2013, 3:19am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/51 "2013-12-07T03:19:19Z")
Couple things not mentioned thus far: Not just power, but traction gets to be an issue. The required forward force as supplied by the drive wheels increases with the square of speed. At some point the tires will not have enough traction to overcome air resistance, but before that happens you might not have enough left over traction to turn or even maintain straight line stability. The suspension must maintain downward force on the wheels at all times lest they break traction, and this is not simple at high speed. Braking: you need to be able to stop. The brakes must absorb energy that increases as the square of speed. Because tire traction limits braking rate the distance also increases as the square. This demands that the driver stay well ahead of the vehicle. Cooling has been mentioned, but not the notion that you can only make air go through typical radiators at around 40-50 mph. At 200 mph you want a smallish air intake followed by a diffuser to slow the air down before the radiator, then a nozzle to speed it back up…otherwise you have a ton of drag. See P-51 mustang aircraft for example. As mentioned previously you need to Provide enough cooling for the high power required, but the higher airspeed does’t make it easier to achieve. Aerodynamic forces increase with the square of velocity. At 200 mph the wrong body shape can easily left the car enough that the wheels lose traction. The right body shape can help It stick to the ground, but a big bump could llift the nose enough to turn it into a wing. The body also needs to work with 30 mph crosswind gusts just in case a thermal breaks off at the wrong place. ---
**Author:** ![Terry\_Kennedy](https://avatars.discourse-cdn.com/v4/letter/t/c57346/32.png) [@Terry\_Kennedy](https://boards.straightdope.com/u/Terry_Kennedy)\ **Post date:** [December 8, 2013, 3:06am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/52 "2013-12-08T03:06:10Z")
> [@slowlearner](#): > > I was amazed at how easy it is now for all the shade tree mechanical geniuses in rural Texas to get 1000 HP out of an old 60’s Detroit V8 just by buying ‘tech.’ Street racing is too expensive anymore or I bet there’d be all kind old muscle cars bopping around here at 200mph, shades of Tiny Lund. GM Racing got 1400HP out of a 2.0L inline 4 (LSJ). I have a friend who built one that runs around 500HP and has a redline of 12,000 - he routinely runs \> 11,000 on the track. All of this costs lots of money if you want a “reliable” engine, and even GM Racing’s official 1400HP needs a rebuild after less than an hour of run time. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [December 8, 2013, 4:34am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/53 "2013-12-08T04:34:20Z")
> [@Kevbo](#): > > The suspension must maintain downward force on the wheels at all times lest they break traction, and this is not simple at high speed. Not simple - but a lot easier than at low speed. Because, as you note, there’s serious airflow to work with. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 8, 2013, 4:59am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/54 "2013-12-08T04:59:42Z")
Speed is a function of cubic money. How fast can you afford to go? ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [December 8, 2013, 5:21pm UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/55 "2013-12-08T17:21:23Z")
Our stock late-model Corvette model (not our car, but the same model) has been tested at 201 mph on a long straightaway, and it was only $56k new in 2008. With a “power chip” the version they tested at hit 208. Was it safe at that speed? Almost assuredly not. ---
**Author:** ![gaffa](https://avatars.discourse-cdn.com/v4/letter/g/e68b1a/32.png) [@gaffa](https://boards.straightdope.com/u/gaffa)\ **Post date:** [December 8, 2013, 9:08pm UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/56 "2013-12-08T21:08:15Z")
> [@Kevbo](#): > > Couple things not mentioned thus far: > > Not just power, but traction gets to be an issue. The required forward force as supplied by the drive wheels increases with the square of speed. At some point the tires will not have enough traction to overcome air resistance, but before that happens you might not have enough left over traction to turn or even maintain straight line stability. The suspension must maintain downward force on the wheels at all times lest they break traction, and this is not simple at high speed. There’s an easy solution for that. > [@](#): > > Braking: you need to be able to stop. The brakes must absorb energy that increases as the square of speed. Because tire traction limits braking rate the distance also increases as the square. This demands that the driver stay well > ahead of the vehicle. The solution for that is also easy. > [@](#): > > Cooling has been mentioned, but not the notion that you can only make air go through typical radiators at around 40-50 mph. At 200 mph you want a smallish air intake followed by a diffuser to slow the air down before the radiator, then a nozzle to speed it back up…otherwise you have a ton of drag. See P-51 mustang aircraft for example. As mentioned previously you need to > Provide enough cooling for the high power required, but the higher airspeed does’t make it easier to achieve. Get rid of them. > [@](#): > > Aerodynamic forces increase with the square of velocity. At 200 mph the wrong body shape can easily left the car enough that the wheels lose traction. The right body shape can help > It stick to the ground, but a big bump could llift the nose enough to turn it into a wing. The body also needs to work with 30 mph crosswind gusts just in case a thermal breaks off at the wrong place. They solved those problems with the Eliica, an [8 wheeled electric car that does 0-60 in 4 seconds and hits 230 mph.](https://en.wikipedia.org/wiki/Eliica). Their web site is dead, I don’t know when. Possibly all the developers got poached by commercial electric car makers. But it’s a really amazing vehicle, with electric motors in all 8 wheels. [They had the goal of 250 mph,](http://www.gizmag.com/eight-wheeled-japanese-electric-supercar-shooting-for-250mph-land-speed-record/10702/) and I’m not sure if they ever hit it. ---
**Author:** ![bengangmo](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@bengangmo](https://boards.straightdope.com/u/bengangmo)\ **Post date:** [December 9, 2013, 2:37am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/57 "2013-12-09T02:37:23Z")
> [@Svejk\_1](#): > > Just wanted to point out that for most of the people that design cars like this, 200 mph is around 320 kph and not exactly a round number. That’s pretty much what made me think of it - to me, 200mph is rather arbitrary. I don’t know any of the engineering, I just rather suspect that “200” being a round number has a lot to do with it - and I’d have to wonder why we aren’t talking about say 300 or 350 km/h ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [December 9, 2013, 2:44am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/58 "2013-12-09T02:44:36Z")
> [@gaffa](#): > > They solved those problems with the Eliica, an [8 wheeled electric car that does 0-60 in 4 seconds and hits 230 mph.](https://en.wikipedia.org/wiki/Eliica). To quote from the link: > [@](#): > > The car has eight wheels to improve traction, and they are smaller than normal passenger vehicles, so it can be lower to the ground for better aerodynamics and stability. Great if you want to go fast; not so great for getting through snowdrifts. 😛 ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [December 9, 2013, 3:10am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/59 "2013-12-09T03:10:33Z")
> [@bengangmo](#): > > That’s pretty much what made me think of it - to me, 200mph is rather arbitrary. I don’t know any of the engineering, I just rather suspect that “200” being a round number has a lot to do with it - and I’d have to wonder why we aren’t talking about say 300 or 350 km/h Because we’re talkin’ good old American _ **miles** _. The way Gawd intended it. 😃 ---
**Author:** ![zoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zoid/32/336_2.png) [@zoid](https://boards.straightdope.com/u/zoid)\ **Post date:** [December 9, 2013, 4:05am UTC](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623/61 "2013-12-09T04:05:32Z")
> [@apple6](#): > > EMU 's battery is not environmentally friendly . Secondly, it is not so strong power , and finally, in some cases in some places ,[Алюмосиликатный наполнитель](http://ru.silicon-gel-china.com/product)would be inconvenient . Such as rescue, if there no electricity, your car will waste, and oil is not the same. Reported [Previous page](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623.md?page=2) [Next page](https://boards.straightdope.com/t/why-is-is-so-difficult-to-engineer-a-car-that-can-go-over-200-mph/675623.md?page=4)