Fifth Gear - Do Fuel Additives really make you faster?

Fifth Gear investigates whether fuel additives improve the performance of your car like they claim.

Category:

Autos & Vehicles

Tags:

• Fifth
• Gear
• cars
• Vicki
• Butler-Henderson
• fuel
• additives
• tom
• ford
• Butler
• Henderson
• Tiff
• Needell
• Jonny
• Smith
• Jason
• Plato

[a1ephzero]

Fuel additives generally have no effect on naturally aspirated engines, because they generally raise the octane, or amount of oxygenates of the base fuel. This allows higher compression to be achieved before engine knock occurs, something that is not adjustable on a NA engine. On a turbocharged vehicle, upping the boost increases the "dynamic" compression ratio, makes more power, but more knock, hence where premium and race fuels come in as well as fuel additives, all the way up to alcohol.

[bigphantom75]

Hmmm.... they all went down 2%. That surley is an extreamly odd coincidence... perhaps another control run should have been made.

[Devourer221]

@a1ephzero What you say is not correct because in a variable valve timing system the timing can be modified in a naturally aspirated engine by the type of fuel being burnt....

[daveofpc]

if you read the bottles, at least the stp one i think it says something like it will increase your octane by about one half of a number from what the pump said... so a 93 octane would now be 93.5

[hero00161]

its made so that you dont fuck up parts in your car to give a smoother drive at high hp the engins are pushing and it dose improve hp if your engine is setup for it

[IROCwarriorAMC88]

A Civic isn't a performance car by any measure so that was pretty dumb to do at the end. Instead use a Camaro V8 or some other V8 engine to test next time. Overall, I agree with the video and I'm surprisingly shocked about the STP stuff. You get what you pay for!

[SourdoughMusk]

@SourdoughMusk I meant to say "the fuel can withstand higher in-cylinder temps during the compression stroke (caused by high compression or high boost in FI) prior to ignition by the spark plug." As compared to regular unleaded gasoline.

[SourdoughMusk]

@ljcalma14 Octane rating simply denotes resistance to pre-ignition. It is in NO way representative of the energy content of the fuel. In fact in means the fuel can withstand higher in-cylinder temps (caused by high compression or high boost in FI) prior to ignition by the spark plug.

[bullet50000]

@bigphantom75

well, maybe they all have roughly the same composition.

[spacecadet35]

My guess why the fuel's power decreases by 2% is becasue they add about 2% additive to the fuel. This additive is unlikely to burn as well as the fuel it is displacing.

[crappyMCcrapperson]

@jasonp31 humbug, this is a correct test. majority of tools who use this stuff have minor bolt on bits on their cars and think this crap will bridge the gap from road car to race car.

[ljcalma14]

Looks like nobody really knows what octane rating means. It is used to reduce engine knock due to PRE-IGNITION. Therefore, it reduces heat energy so that the compressed air-fuel mixture won't ignite too early. Higher octane rating fuel contains less heat energy which equates to less power and less fuel economy.