(1 Litre ) HYDRA EHN-99 2-EHN Cetane Enhancer Fuel Additive

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Description & Details

Summary

  • 99% Pure 2-EHN 2 Ethylhexyl Nitrate cetane improver 4 to 8 points.
  • Improves performance and economy whilst reducing harmful engine emissions.
  • Reduced engine knock with smoother running and better pickup.
  • Cetane Booster for diesel, red diesel, biodiesel diesel, ULSD, MGO etc.
  • 50ml Treats Up To 50 litres of fuel.

(1 Litre ) HYDRA EHN-99 2-EHN Cetane Enhancer Fuel Additive Description

Feature & Advantages

  • A 99% Pure 2-EHN 2 Ethylhexyl Nitrate cetane improver, increase cetane by up to 4 to 8 points is the ideal diesel treatment additive
  • Use for cetane booster diesel engine applications improves performance and economy used in all types of diesel engines whilst reducing harmful engine emissions
  • In fuel treatments, EHN-99 is the ideal product to give a cetane boost diesel, a performance enhancer that improves performance and economy, reduced engine knock with smoother running and better pickup
  • Cetane Booster for diesel, red diesel, biodiesel diesel, ULSD, MGO etc

USAGE

Add to fuel tank then top up with new fuel. Fuel tanks being treated should be at least 10% full. Usual dose at 1:1000 to 1:500 depending on the quality of fuel and performance increase required. Can be used in all grades of diesel fuel including biodiesel fuels.

Dose Rate 1:500. Add 1ml Hydra EHN-99 to 0.5 litres of fuel.

Dose Rate 1:1,000. Add 1ml Hydra EHN-99 to 1 litre of fuel.

HOMEMADE DIESEL FUEL

Diesel fuel made from natural oils and fats has a much lower cetane number than diesel made from hydrocarbon sources.

Diesel engines require a minimum cetane number to run correctly. In Europe, diesel fuel is manufactured to a European Union specification i.e. EU 590. Fuel meeting this specification has a minimum cetane number of 51 and premium diesel fuel can have a cetane number as high as 60.

Therefore, if you are making diesel fuel from a natural source it is necessary to add a cetane booster such as Hydra EHN-99 to your fuel, 2-EHN is the standard cetane booster, approved by all governments and used worldwide. It is not necessary for the product to contain a lubricant as there is sufficient lubricity from the fats and oils that the homemade diesel is made from.

Hydra EHN-99 delivers an increase in Cetane number to your Diesel and MGO fuel. It will increase the cetane number by up to 4 to 8 points depending on the quality of fuel being treated.

Hydra EHN-99 provides an economic route to meeting quality specifications and a platform for creating premium fuels. Diesel bug treatment improves fuel combustion by reducing the ignition delay period resulting in easier cold starting, reduction in white smoke, harmful emission reduction, and reduced noise from the engine. Better fuel combustion means improved fuel economy.

HYDRA EHN-99 delivers an increase in Cetane number to your Diesel and MGO fuel. It will increase the cetane number by up to 4 to 8 points depending on the quality of fuel being treated. Hydra EHN-99 provides an economic route to meeting quality specifications and a platform for creating premium fuels and it is perfectly suitable for all diesel and biodiesel fuel. Better fuel combustion means improved fuel Performance and Economy on any diesel engine.

IMPORTANCE OF CETANE

The overall quality of diesel fuel is dependent on a number of factors. These include BTU value, viscosity, pour flow point, aromatic and paraffinic content, and resistance to contaminant build-ups such as water and bacteria. A diesel fuel's quality also is very dependent on its cetane number.

The cetane number (CN) is an index of the ignition point or combustion quality of diesel fuel and is measured using an ASTM D613 test. 

Standard European BS EN590 diesel from the pump normally has a minimum cetane number of around 51, with premium diesel a little higher. Depending on engine design, driving conditions, and so on, the optimum cetane value for most vehicles is around the mid to high 50s.

Matching cetane to the engine is important in order to maximize the engine's performance. Biodiesel fuels in particular, especially homemade brews, usually start with a much lower cetane number so cetane improvement for these fuels is essential.

A fuel with too low of a cetane number for a particular engine will result in reduced cold-start ability, rough running, excess engine noise/vibration, and reduced combustion quality.

This leads to reduced performance, excess emissions, and carbon build-up throughout the engine and emission system components (intake, EGR, DPF etc.).

A higher cetane fuel that is a proper match for the engine will reduce ignition delay, improve overall combustion quality, liberate more BTU (energy) from the fuel, and improve performance and MPG. It also will reduce engine noise, deposit build-up, and exhaust emissions. 

Diesel and MGO fuels with cetane numbers lower than minimum engine requirements can cause rough engine operation. They are more difficult to start, especially in cold weather.

Many low cetane fuels increase engine deposits resulting in more smoke, increased exhaust emissions, and greater engine wear. Using fuels that meet engine operating requirements will improve cold starting, reduce smoke during start-up, improve fuel economy, reduce exhaust emissions, improve engine durability, and reduce noise and vibration.

Hydra EHN-99 delivers an increase in cetane number to your diesel and MGO fuel. It will increase the cetane number by up to 8 points depending on the quality of fuel being treated.

It provides an economic route to meeting quality specifications and a platform for creating premium fuels. Improves fuel combustion by reducing ignition delay.

What should I look for in a cetane booster?

Contrary to some propaganda, alkyl nitrates still offer the greatest improvement in cetane number, with measured increases of up to eight points. 

When it comes to alkyl nitrates, 2-Ethylhexyl nitrate (2-EHN) is the most popular and most respected.  

It offers more consistent ignition quality whilst reducing unwanted and negative combustion conditions.

Fuel additive manufacturers recognize both the benefits of boosting the cetane number and using 2-EHN so much now that most offer cetane improvers. 

The question, in this case, is what are you getting for your money?

From the close examination, it appears many cetane boosters contain useless fillers. To maximize profits most manufacturers still insist on the single bottle per tank philosophy. 

Some 200-300ml bottles that treat a single tank of fuel have as little as 20% active ingredients. 

This is lucrative for the manufacturer but not a good value for the consumer. Therefore, it is important to understand what you are getting for your money.

The optimum amount of 2-EHN is around 30-100ml per tank of fuel, depending on the engine and base cetane level. 

As 2-EHN can reduce lubricity it is important that the fuel contains sufficient lubrication. Home made bio-diesel is perfect for this as it has more lubricity than normal diesel.

To ensure you are getting the best value, make sure the product contains at least 50% 2-EHN.

Hydra EHN-99 is ideal as it is 99% pure 2-EHN (2-Ethyl Hexyl Nitrate).

So, what do we recommend and why?

Active cetane improvers are essentially a form of fuel modification, or more accurately, combustion modification.

When combined with the correct fuel catalyst technology, latest Nano detergents, and lubricity additives, they can turn the most mediocre pump fuels and biodiesels into super diesel that will outperform the best premium pump fuels.

Rather than introduce another diluted cetane booster, Hydra decided to release a concentrated chemical product that contains 99% active ingredients.

It provides optimum increases in cetane whilst being able to treat multiple tanks of fuel, rather than just one tank.

Hydra EHN-99 contains a minimum 99% 2-EHN this ensures that your fuel receives the maximum cetane boost. Giving an optimum combustion condition to ensure a better fuel burn, smoother engine and more mpg.

International Standards:

All of our products are manufactured to the highest specifications at our UK plant, which is accredited to ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018.

Details

OPC P7B6CWB
Brand
HYDRA
Codes 5055816635330 (EAN)
Rank Bestseller

Product Images

(1 Litre	) HYDRA EHN-99 2-EHN Cetane Enhancer Fuel Additive 1
(1 Litre	) HYDRA EHN-99 2-EHN Cetane Enhancer Fuel Additive 2
(1 Litre	) HYDRA EHN-99 2-EHN Cetane Enhancer Fuel Additive

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Reviews of (1 Litre ) HYDRA EHN-99 2-EHN Cetane Enhancer Fuel Additive

All OnBuy Reviews are Verified Reviews

Overall Rating:
5
18 Reviews
4
4 Reviews
3
0 Reviews
2
0 Reviews
1
0 Reviews
Highest Rated Review
5/5
M. Lauchlan
Posted 29/07/2026
All good it does seem to quite my engine
Filter Reviews
5/5
M. Lauchlan
Reviewed from GB
Posted 29/07/2026
Product 1 Litre
All good it does seem to quite my engine
5/5
D. Beniston
Reviewed from GB
Posted 21/07/2026
Product 1 Litre
Fast delivery and good product!
4/5
C. Dobrea
Reviewed from GB
Posted 21/06/2026
Product 5 Litre (+ Dosing Bottle)
All good
5/5
P. Amos
Reviewed from GB
Posted 05/06/2026
Product 1 Litre
Good value for my a160 as it needs a clean out
5/5
S. Petersen
Reviewed from GB
Posted 18/05/2026
Product 2x5 Litre (+ Dosing Bottle)
Exactly what I was looking for and very competitive pricing.
5/5
W. Ashworth
Reviewed from GB
Posted 18/05/2026
Product 1 Litre
Very happy with product does exactly what it is supposed to
4/5
G. Herbert
Reviewed from GB
Posted 13/04/2026
Product 5 Litre (+ Dosing Bottle)
Good value and delivered quickly
4/5
S. Smithson
Reviewed from GB
Posted 05/04/2026
Product 2x5 Litre (+ Dosing Bottle)
Arrived promptly, well packed as described, am happy, would buy again.
5/5
J. Goff
Reviewed from GB
Posted 05/04/2026
Product 1 Litre
Fantastic product and service. Definitely use again.
5/5
S. Goss
Reviewed from GB
Posted 15/03/2026
Product 5 Litre (+ Dosing Bottle)
Very pleased with the delivery. Came on time and the item was very well wrapped. With no damage or leaks.
OnBuy.com. well done.
F
5/5
G. Boyd
Reviewed from GB
Posted 06/02/2026
Product 5 Litre (+ Dosing Bottle)
Excellent customer service very happy with my product too thank you
5/5
J. Bell
Reviewed from GB
Posted 11/01/2026
Product 5 Litre (+ Dosing Bottle)
Fast and efficient dispatch and delivery.
A good product
5/5
J. Green
Reviewed from GB
Posted 17/11/2025
Product 1 Litre
I’ve been using this product for while and I find it improves my cars performance no end
5/5
U. Dagia
Reviewed from GB
Posted 09/09/2025
Product 2x1 Litre
Very good product I could instantly see the results on my car performance
5/5
A. Supuran
Reviewed from GB
Posted 25/03/2025
Product 5 Litre (+ Dosing Bottle)
I drive my car all day in taxi regime and I felt the difference straight away.
5/5
A. Junik
Reviewed from GB
Posted 09/03/2025
Product 5 Litre (+ Dosing Bottle)
I am happy with the product.
Very good price
5/5
C. Devonport
Reviewed from GB
Posted 26/01/2025
Product 1 Litre
Happy with the purchase arrived quickly and as cheap as anywhere else online so would use again in the future definitely
5/5
D. Jones
Reviewed from GB
Posted 25/08/2024
Product 1 Litre
Very happy and a lot cheaper than paying for v power diesel this stuff does more, been using it for a few years now and everything runs smoothly
5/5
S. Clover
Reviewed from GB
Posted 25/08/2024
Product 1 Litre
Used this for some time now and it does make a difference, great price. Engine is definitely smoother with this in the tank.
5/5
J. Hems
Reviewed from GB
Posted 18/08/2024
Product 2x5 Litre (+ Dosing Bottle)
This additive is excellent. Not only does it keep your engine clean (less emissions) it gives you more power and 3mpg more per gallon. Highly recommended ii you do a lot of miles or town work.
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