[[quoteright:350:[[Film/SpeedRacer http://static.tvtropes.org/pmwiki/pub/images/overdrive.jpg]]]]
[[caption-width-right:350:Yes, that's the one for Overdrive!]]

->''"The pod race in the film suffers from a common trope, in which characters needing to go somewhere really fast head off in their vehicle. At some point they realise they're not going to make it in time, so they open the throttle all the way and go even faster. The question of course being why weren't they going as fast as they possibly could already?"''
-->-- ''Webcomic/DarthsAndDroids'' Episode 105, ''Burning Bridges''

A character needs to drive somewhere quickly. Maybe they're in a car race, or maybe they're just racing against time. At one point, they realize they're not going to make it in time. So they... go faster. [[FridgeLogic Huh?]] Why didn't they just drive that fast to begin with?

Odd as it may seem, this unexplained increase in speed can have some basis in reality. It can be simplified as a cost vs. benefit decision. If somebody has 'nothing to lose' and ''must'' be somewhere at a certain time then they have to speed up - BUT - if they push their machine too hard it will fail before they get there. If they had backed off slightly, then it could have broken down ''after'' they had arrived. In a race a driver will hold back simply because there's a notable difference between "the fastest they can drive" and "the fastest they can continuously drive without wear and tear [[PhlebotinumBreakdown completely destroying the engine halfway through the race]]". Smart drivers limit themselves to the latter, and use the engine-wrecking speeds in short bursts--or for those desperate final laps.

Fuel consumption is also a potential problem. Having to find out where to refuel in the middle of some prairie or ocean is ''not'' a way to get to destination ASAP. Running out of propellant halfway to the next planet and thus unable to decelerate is not a good idea either. The cost of fuel, oil (or Helium-3, or whatever) and repairs is also a factor. In most cases engines are supposed to work much longer than one or two rides and generally engines aren't so cheap that the cost of damaging one could be disregarded without a really good reason.

Then there are NitroBoost systems, which are of limited duration by definition, and speed limits. On normal roads, a driver may initially be unwilling to flagrantly violate the speed limit--and risk bringing the ire of the police down on them--until they get ''really'' desperate.

Of course, in spite of the risks associated with such insane speed, it almost invariably results in victory for our protagonist, rather than catastrophic engine breakdown in the penultimate lap. LudicrousSpeed laughs at your puny physics and mechanical stress limits!

And of course, there are some instances--say, short drag races--where this trope makes absolutely no sense no matter how you slice it.

If the villain does this, don't worry. DickDastardlyStopsToCheat, every time.

A SubTrope of HoldingBackThePhlebotinum and MiracleRally when it's in a race. A SisterTrope of TimTaylorTechnology, and the mechanical equivalent of a DangerousForbiddenTechnique. If it involves the risk of a catastrophic failure, it's ExplosiveOverclocking.

Close to, but not to be confused with, the ''VideoGame/FinalFantasyX'' move called Overdrive (which is listed under LimitBreak).


[[folder:Anime & Manga]]
* In ''Anime/TheVisionOfEscaflowne'', when Van, Allen and Hitomi are escaping Zaibach's capital on Escaflowne (which transforms into a dragon for flying) they are pursued by Zaibach's mechas which are much faster. As they're closing in and a panicked Van is urging Escaflowne to fly faster, it suddenly transforms to reveal a jet engine and shoots forward at LudicrousSpeed.

* In ''[[FanFic/HalfLifeFullLifeConsequences Half Life: Full Life Consequences]]'', John Freeman's reaction to his brother being in mortal danger is to try to reach him by going "fast" on his motorcycle. And then events happen that cause him to go "faster", ''three times''. Even though it was established that he ''was in a huge hurry and didn't have time to waste''. So, basically, he felt his brother wasn't in ''that'' much danger at first.
** But at the end of chapter 2, Gordon does berate him for getting there slow, as he is [[spoiler: now a zombie [[strike:ghost]] goast]].
** And in that same chapter it's established that John Freeman has another, faster motorcycle, which was unfortunately out of gas in the first chapter. How it was refilled in-between is a mystery.
* In the ''Franchise/FinalFantasy'' fan fic [[http://www.lakupo.com/qu/fanfics/cid_wars.html "Cid Wars"]], the characters are at one point trying to get somewhere by van, and each time someone said they needed to go faster, the driver upshifted. This happened a total of ''eight'' times, complete with one of the characters asking [[LampshadeHanging "Just how many gears does this van have?"]]

* The podrace from ''Film/StarWars: Episode I - Film/ThePhantomMenace'' is all over this trope. Sometimes Anakin passes other racers with ease, and other times he keeps pace with Sebulba over long straightaways. It also genuinely makes zero sense that he wasn't going as fast as he could to begin with, considering how he started the race in last place due to engine failure and his freedom was on the line.
* ''WesternAnimation/{{Cars}}'' is a rare subversion of the "more speed always works'' aspect of the trope: Lightning [=McQueen=] gains a whole lap on Chick Hicks and The King by skipping several pit stops--then both of his rear tires blow out in the final lap, and the race ends in a three-way tie.
* In ''Film/GalaxyQuest'', the overdrive blows-out after being held down too long, leaving the ship nearly crippled.
* The protagonist of ''My Science Project'', a car mechanic by hobby, has a supercharger equipped on his car, which he uses to outrace an energy surge ([[MST3KMantra just go with it]]) racing down power lines, to cut off the ImportedAlienPhlebotinum device before it gets more power to warp time and space even further than it had already done to that point.
* Done with a horse at the end of ''TrueGrit''. Rooster Cogburn rides a horse so hard and fast that it eventually dies just short of his destination.
* In the film ''Fail Safe'' (think ''Dr. Strangelove'' played for drama) in order to catch up to a bomber with a nuke which is about to destroy Moscow a group of pursuing US fighter jets are ordered to use their afterburners to increase speed, even though everyone ''knows'' that they'll just run out of fuel early and crash in the ocean.


* In James Blish's ''Literature/CitiesInFlight'' novels, the cities of the title can fly at faster-than-light speeds, but they're all equipped with a gadget called "Situation N" which can instantly teleport them away from trouble. Only thing is, it can only ever be used once per city. Why? Because if they used it more than once it would be too convenient for the author, I guess.
** This is really a ''FridgeLogic'' issue. A city's "City Fathers" AI has this "Standard Situation N" last resort action that turns loose their accumulated information store to produce some unpredictable solution, which is then wiped from memory to prevent lazy city managers or mayors from using it frivolously. (Why would it be frivolous to use it all the time? Because it's automatically wiped from memory, so that would waste their one last-resort option . . . er . . . wait a minute . . .) In this particular case (near the end of ''Earthman's Burden'') it teleported the cities involved away from an untenable situation; but the leaders didn't know in advance exactly what would happen. It's hard to think of a clearer case of ''deus ex machina''; yet Blish presents the gimmick so convincingly that it took this troper, at least, many a reading before the circularity of the reasoning dawned on him.
* Military warships in ''Literature/HonorHarrington'' series has a version, though with acceleration rather than top speed. The inertial compensator that allows the crew to survive the hundreds of gravities their drives are capable off is normally only run to 80% of its theoretical maximum capacity to reduce wear and reduce the risk of failure. It ''can'' be run higher in emergency situations but is not recommended because if it fails you have precisely zero seconds of warning and then the entire crew is reduced to a red smear. This ''has'' happened "on screen," too-- though less times than it probably should have, given the stated risk and the number of time's it's been chanced.
** A similar situation exists with the hyper generators that allow FTL but it is much rarer. The option to take the inertial compensator to full power is built in but to run the hyper generator requires physically disabling the safeties. The effect of trying to go into higher levels hyperspace and failing is described as "bouncing."
** In the end the situation is like the Space Shuttle, the actual safe speed is higher than listed. Over time Manticore finds they can push their compensators (after upgrades based on Grayson's less refined but ''fundamentally'' superior type of compensator) much higher than listed, and that 80% of that is hopelessly cautious. Solarian technology isn't so robust; a Solly Admiral is thought to be bold by Solly Standards to seek 85% in a battle.
** And all this is before considering that the Manticorans typically limit themselves even further in peacetime so as not to tip potential enemies off about their capabilities before they actually have to fight them.
* Deconstruction in the Literature/SwordOfTruth, where it turns out that your horses do have a maximum output. You can push them past that... and you'll run them into the ground. Later in the series they've become genre savvy about this, and start taking extra horses so that they can switch them out and avoid the negative aspects of this trope.
* In the Creator/RobertAHeinlein short story "Sky Lift", the pilots of a continuous-boost "torch ship" are forced to maintain multiple-G acceleration, right at the edge of their physical tolerance, for days while rushing to deliver medical supplies to a colony facing an epidemic. [[spoiler:They succeed, but one dies and the other is prematurely aged by the experience, leaving him permanently physically impaired and with cognitive problems very similar to senility.]]

* ''Franchise/StarTrek'' was a frequent offender. ''[[Series/StarTrekTheOriginalSeries The Original Series]]'' played this completely straight. ''[[Series/StarTrekTheNextGeneration The Next Generation]]'' explained that speeds beyond Warp 5 damage the fabric of space-time. ...Then a new warp engine was invented that ''didn't'' damage space-time, completely erasing the prior justification.
** At least in TNG and later the energy requirement grew exponentially with the speed, thus if the matter wasn't urgent, they went slower to conserve fuel.
** In ''The Wounded'', the matter is very urgent, yet they decide to go Warp 4 so that the writers can have them step on the gas later when things go really bad.
* Super Pursuit Mode in ''Series/KnightRider''. This is explained by a simple application of physics: aerodynamic downforce ''reduces'' the vehicle's speed, since the air resistance of the vehicle is increased (there's more surface area for the wind to hit). What Super Pursuit Mode accomplishes is increasing K.I.T.T.'s ''maneuverability'' at high speeds, thus preventing Michael from wrapping K.I.T.T. around a power pole[[note]]or rather, wrapping a power pole around [[MadeOfIndestructium K.I.T.T.]][[/note]]. The game makes this point, too. Your maximum speed is decreased a bit, but it's much easier to steer.
* Hyperthrust in ''Series/StreetHawk'', which required a planned route and clearance from MissionControl before use.

* ''[[TabletopGame/BattleTech [=BattleTech=]]]'''s [=BattleMechs=] can be equipped with myomer acceleration signal circuitry (MASC for short), which when active provides about a 33% boost to maximum speed by making the 'Mech's artificial leg muscles contract that much faster. There is, however, always a chance that the added strain will result in internal leg damage, and this chance increases rapidly if the system is used over multiple turns in a row, wherefore it's useful primarily to provide short emergency bursts of speed. An alternative -- and incompatible -- approach involves using special extra-strong myomer fibers in the first place; unfortunately, those require the 'Mech to run hot enough for its weapons to start to incur to-hit penalties before their performance exceeds that of the normal version. (To make the most of these 'triple-strength myomers', a 'Mech's heat level should ideally stay at ''exactly'' 9 -- no lower, no higher, on a scale from 0 to 30 -- for extended periods.)

* Boost in the ''VideoGame/{{Motorstorm}}'' series works this way. You have an unlimited supply of Boost, but using it heats up your engine. if you don't lay off the boost, or drive through water to cool your engine down, it will blow out your engine, respawning you near last place.
* ''VideoGame/RomancingSaGa: Minstrel Song'' has Hasten Time and Overdrive, the ultimate [[MakingASplash Hydrology]] spells. Casting one of these babies lets the user instantly end the enemy's turn and either give themselves and all their allies a free turn to act -- or act ''five times in a row'' themselves, without any fear of interruption. However, the spell's big drawback is that it's a ''major'' drain on your MP, especially in Overdrive... is it worth having your caster attack five times uninterrupted when it will then take them several turns to recover?
* ''VideoGame/StarWarsEpisodeIRacer'' makes the engines overheat and burst into flames if Boost Mode is not turned off before too long, which can result in your engines deteriorating [[GameplayAndStoryIntegration (which nicely explains why Anakin wasn't boosting the whole time in the film)]]. And unless you pay for the rather expensive repairs, you'll start the next race with a half-broken engine. In the sequel, ''Revenge'', your engines won't catch fire anymore, but boosting while overheated will constantly damage your engines, leaving you vulnerable to being knocked out if you hit a wall or get attacked by another racer until you take time to repair the damage.
* Similarly, in ''VideoGame/FZero'' (from X onwards), you can boost whenever you want after the first lap, but doing so [[CastFromHitPoints drains your health]]. Boosting in a pit area is essentially free, but cuts down on the amount of time you can spend there to repair any other damage.
* An armor attachment in ''VideoGame/{{Dogyuun}}'' allows the player to move very quickly as long as they hold down button 2, with ''no drawbacks whatsoever''. However, moving around too quickly will make it more likely for you to crash into enemies or bullets.
* Driving at max speed in ''Baja: Edge of Control'' is not recommended, as it will cause the truck's radiator to begin to fail (along with your suspension being repeatedly crushed going over jumps at 100mph); The AI can be seen driving at less than max power most of the time to protect their engines, which is critical in the long point-to-point rally tracks.
* When [[EvilKnockoff Metal Sonic]] falls too far behind in the race with him in ''VideoGame/SonicTheHedgehogCD'', he'll overclock his systems to trigger a move called the "V. Maximum Overdrive Attack", which greatly increases his speed and surrounds him in a destructive energy field. [[AllThereInTheManual Supplementary materials]] explain that this technique places enough of a strain on Metal's body that prolonged use could cause him to self-destruct.
* The ''VideoGame/MarioParty'' mini-game "Slot Car Derby" punishes players who maintain the maximum speed for too long on tight turns by making the car spin around for a second and have to accelerate from zero again. A common strategy is to ease off on the analog stick just before this happens, watching for the puffs of smoke that serve as a warning, then pump it back to maximum the very next second.
* The ''VideoGame/ArmoredCore'' series has Over Boost, which allows an [[HumongousMecha Armored Core]] to move much faster than normal by consuming enormous amounts of energy. Depending on the title, it may also overheat the AC or consume [[DeflectorShields Primal Armor]], leaving you nearly defenseless
* ''[[Videogame/MechWarrior MechWarrior Living Legends]]'''s various NitroBoost systems - MASC on [[HumongousMecha battlemechs]], afterburners on [[SpacePlane aerospace fighters]], and turbo on [[TankGoodness treaded]]/[[TanksButNoTanks wheeled tanks]] - all generate [[OverHeating excess heat when used]]. Aerospace fighters have the most extreme heat generation, to the point where it's easy for them to melt their own fusion reactor while trying to flee danger, whereas most tanks can boost almost indefinitely. On [[LevelEditor community-made]] race maps, players have to handle both their heat (doubly so if it's [[WackyRacing weapons-live racing]]) and stay on the track; not too difficult on most tanks, very difficult on the {{Hover Tank}}s which have heat-free boost, but are highly unstable and prone to flipping and sliding off the track.

* ''Webcomic/DarthsAndDroids'' attempts to make sense of the ''Star Wars'' podrace by [[http://www.darthsanddroids.net/episodes/0105.html completely reinterpreting what happened at the end of the race.]] TheRant below that strip discusses this trope (and directly inspired this very article).

* Used in the pilot episode of ''WesternAnimation/TaleSpin''. Up until then, the overdrive existed, and it was clearly stated that you could only use it for so long before the engine overheated and blew up the Sea Duck. Baloo burned it out forever and ever during the episode; it's just as well, so we couldn't complain about him ''not'' using it in future episodes.

* The term "Overdrive" in RealLife simply means the output spins faster than the input. Nothing more, nothing less. In a car, this reduces engine speed for a given road speed, reducing fuel consumption. Every car will, in fact, be ''slower'' in an overdrive gear than in direct drive or underdrive as the engine will be at a mechanical disadvantage and have to work harder to achieve the same acceleration. Yes, the wheels can spin faster, giving a theoretical high top speed, but in Overdrive, the engine may not have the torque to accelerate to those speeds. This is exactly why your car's transmission, automatic or [[DrivingStick manual]], has low gears in the first place.
* Many World War II-era fighter aircraft featured an engine setting called "[[http://en.wikipedia.org/wiki/War_emergency_power War Emergency Power"]]. It was intended for emergency use in combat and normally had a time limit imposed on its use, as it would wear out the engine in a very short time. WEP appeared in many forms; some aircraft engines simply had the capacity to run at power levels that would overstress their own components. In these cases, a piece of tape was inserted to stop the throttle at the maximum safe setting; if the tape was broken, the engine would need to be inspected after the flight. Other aircraft implemented WEP through the use of consumable additives. Nitrous oxide injection would cool the fuel/air charge (allowing more fuel and air to enter the cylinder on each cycle) as well as providing additional oxygen at high altitude. A few aircraft were designed for the stress of nitro injection, and were limited only by the onboard supply of nitrous. Water or water/methanol injection provided a lesser version of the same effect, but also cooled the engine and allowed it to operate beyond its radiator's normal capacity.
** A handful of civilian aircraft -- often those intended for "bush aviation" -- also possess an "Emergency Power" setting. It's facetiously said to provide "just enough power to get you to the scene of the crash."
* The Space Shuttle's main engines were designed for a certain maximum normal output, rated as 100%, but can run at up to 110% thrust in emergency abort situations. After a few flights it was determined that 104% was safe for continuous operation, and it was easier to routinely go to 104% than to rewrite all the documentation to make that the new 100%.
* Most modern fighter aircraft are equipped with equipment variously known as afterburners (US), reheat (Brit), or forsazh (Rus). This system dumps additional fuel into the exhaust manifold in order to burn any oxygen that was not consumed in the main stage of the engine. This can greatly (~160%) boost the thrust at the cost of extreme fuel consumption; afterburners can empty the multi-ton fuel tanks of a jet fighter in less then 5 minutes. Go really fast if you have to, but do it too long and you'd better be ready to walk home.
** Averted in some planes (like the SR-71 Blackbird) that are designed for high efficiency during afterburn; you can have your engines spittin' flame for as long as there's fuel available, and everything will be ok. The downside is that they are horribly inefficient when ''not'' afterburning. The Blackbird also burned a special fuel, which meant its operating costs followed the plane itself into the stratosphere.
** Afterburners also come with a side effect of a massive thermal signature. This negates a stealth aircraft's stealth by making it visible to thermal sensors, and in general makes it much easier for heat seeking munitions to find their mark even with countermeasures. Modern stealth planes, such as the F-22, utilize a technology known as "supercruise" to travel at supersonic speeds without resorting to their fuel-guzzling afterburners.
* The US destroyer USS ''Samuel B. Roberts'' managed to do this during the Battle of Samar, by ordering the engine crew to push the twin boilers as hard as they would go. This managed to add 5 knots to the speed of the ship while it was under fire, going from the rated 23-24 knots (that the engines were said to max out at) to 28.7 knots. The ship was sunk by gunfire from a Japanese battleship during the battle, and managed to earn itself the title "the destroyer escort that fought like a battleship."
** US Navy slang for the above action is "All ahead Bendix." The ship's speed is controlled by a device which was often made by the Bendix company and their logo was just beyond the maximum setting, so it appeared that "Bendix" was an option for higher speed.
* Many other vehicles, both civilian and military, have a "red line" power setting which represents the maximum power available without immediately damaging the engine, and a lower "yellow line" setting which is the maximum safe cruise setting. For example, the manual for the Turbomeca Arrius 1A (a turbine engine used in helicopters) lists a maximum continuous power of 296 kW, an intermediate contingency rating of 357 kW (120% normal) usable for up to 30 minutes, and an emergency maximum for 2.5 minutes of 388 kW (131% normal). Most aircraft have a "never-exceed speed" listed in their specifications that's some way below their theoretical maximum, to provide a safety margin against excessive airframe stress.
** The original VW Beetle is an exception in that it could safely operate all the way to the red line; in TheFifties, when it was normal for a small car to have a top speed in the range of 70 MPH, the company used this as a selling point.
** Many cars have an aerodynamically-limited top speed, creating a situation where the engine looks like it ought to be able to take you faster, but it doesn't have enough torque to accelerate you.
* For many steam engines, going over a certain amount of power required locking down the automatic valves that were designed to keep the engine from producing more pressure than it could handle. Lock them down for a short while, and your ship gets a bit more power and speed. Do it too long, and you might cause the engine to explode, or overstress some other component connected to the engine and cause it to break.
* When done to computers, it is called [[http://en.wikipedia.org/wiki/Overclocking Overclocking]]. This makes the computer faster, but also generates more heat and can [[ExplosiveOverclocking cause hardware errors or even ruin the CPU if performed incorrectly]].
* Humans (and many other animals) can do something like this. Between adrenalin increasing blood pressure to move more oxygen and fuel to muscle cells, and muscle cells over-performing at the potential cost of both tearing themselves apart ''and'' overheating to death, normal humans can manage to lift cars and outrun sprinters under duress. The reason your average person doesn't perform like an Olympian all the time? They would die very quickly if they kept that over-performance up for longer than a few hours, at best.
* Direct Current electric motors have a natural "balancing speed" where the applied voltage equals the counter-Voltage produced by the rotor itself turning in a magnetic field. A mode of operation known as "shunt" activates additional diverter resistances in parallel with the field winding, reducing the strength of the counter-Voltage and allowing the motor to turn even faster.