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Hondata CANFlex E85 Flex Fuel Kit for Honda Civic

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CARB Compliance / Exemption Warning: If you live in California and your application for this product is not CARB Compliant / Exempt, then you cannot purchase it for public highway or street use (in that case it could only be used for formally sanctioned race use on a racing vehicle that may never be used on a public highway or street). If your application is not CARB Compliant / Exempt and you're shipping to California, our system will let you know on the final checkout page.

What is a Flex Fuel Kit in simple terms? It is basically a special sensor installed along one of your fuel lines that reads the amount of ethanol in your fuel, produces a signal, and sends a processed version of that signal to your ECU for use by your tuning device. Combined with a tuning device, it converts your Honda Civic to run on higher concentrations of ethanol (like E85) than is in standard pump gas.

TIP: Your gas tank is not required to just have all E85 fuel in it after installing this kit (hence the name Flex Fuel). It can have any combination of E85 and non-E85 gasoline in it. Your tuning device will automatically adjust on the fly for your current fuel mixture.

If you live outside the United States, we cannot ship this product to you. This is because we are a USA Hondata dealer, and we can only sell to USA customers.

The Hondata CANFlex is a "49 state" SEMA-certified solution for running flex fuel (E85) on your factory turbocharged Honda Civic. All calibrations are designed to work just fine an otherwise stock Honda Civic (with stock intake and exhaust). Hondata includes CANFlex tunes for FREE in FlashPro Manager, and these tunes can also be used with bolt-ons (additional tuning may be needed with certain parts). The Hondata CANflex FlashPro calibrations deliver a safe, flat torque curve, with opportunity for more with custom tuning! With a flat torque curve, your Honda Civic becomes a lot more controllable and fun to drive. Your Honda Civic will come onto boost earlier and no longer feels like it is falling off boost higher into the rev range!

Key Features:
  • Allows you to run E85 fuel and mix it with regular pump gas.
  • "49 state" legal: passes smog tests. Not CARB legal yet (pending).
  • Potential for huge power/torque gains.
  • Free Hondata CANflex FlashPro calibrations deliver a safe, flat torque curve with the potential for more gains.
  • Helps to spool a turbo earlier and faster.
  • Allows the engine (and turbo) to operate considerably cooler.
  • Enables the ECU to dynamically adjust your tune, for a given amount of ethanol percentage.
  • Very easy Plug and Play (PnP) installation, does not require any cutting/splicing of wires or even routing wires through the firewall (you have the option of routing a small wire through the door seal area instead). Everything can easily be returned to stock. In addition, no factory 0-5V sensors are used up; all data is sent to your ECU directly via the Hondata CAN gateway device (which connects to your factory CAN bus)!
  • Includes fuel line adapter with integrated ethanol sensor, E/B/CAN converter box (Ethanol-Bridge-CAN), E/B/CAN Hondata OBD2 adapter cable, and OBD II adapter.

More Details / FAQ
Q: What is E85 and why does it easily give so much more power?
A: E85 is a biofuel composed of up to 85% ethanol. The remaining 15% of the fuel is traditional gasoline. Keep in mind the ethanol percentage can be lower during the winter months in some areas. The ethanol often is made from corn and is the same type of alcohol you would find in hard liquor, with the exception that fuel ethanol is denatured with additives to make it undesirable and harmful to drink.

The main reason E85 allows for some much more power than traditional gasoline is that it has a very high octane rating, usually from around 100 to 105 octane, compared to 91 to 93 octane from normal gasoline. This high octane rating allows E85 to resist engine knock. Engine knock occurs when areas of the air fuel mixture ignite before the should due to excessive heat for the fuel type used. This is bad because it can cause extra stress on the engine, and doesn't make optimal power either. From the factory, a new engine is almost always "knock limited", which means it cannot achieve its maximum design power on normal gasoline due to engine knock occurring. E85 basically eliminates this constraint, allowing the engine to achieve the maximum power possible. This especially applies to engines that are turbocharged from the factory.

One nice side effect of that is that extra E85 fuel will help cool your combustion chamber and turbo, and thus help maintain maximum power and reliability. E85 fuel is also generally a lot less expensive than normal pump gas too!

Vehicles sold in the U.S. are designed to operate correctly on the factory tune when using fuel that contains between 10% (E10) and 15% (E15) ethanol. E10 is normally found at almost every standard gas pump in the U.S., so you most likely fill up with it all the time. The reason for this is that ethanol has been found to reduce overall emissions while keeping engine performance strong (see https://afdc.energy.gov/fuels/ethanol_benefits.html for more information).

Q: Why a Flex Fuel kit?
A: The "Flex Fuel" part of this kit refers to the ability to run a varying amount of ethanol without having to re-tune or worry about exactly how much E85 you filled up with. In general, the more you fill up with, the more power you get, up to a certain extent. 30-50% ethanol is a typical range for maximum performance and efficiency.

Q: Ok, so what do I need to buy?
A: All you need is this Hondata CANFLex Flex Fuel Kit and a red (Race) Hondata FlashPro (OTHER TUNING SOLUTIONS WILL NOT WORK), along with some E85. This flex fuel kit constantly monitors how much ethanol is in your fuel and then tells the FlashPro, which dynamically recalibrates your ECU to give the optimal power gains on any percentage of ethanol you happen to have in your tank.

Q: Is a custom tune necessary?
A: No, it is not. To get the great performance gains, all you need to do is install this kit, reflash your ECU with the appropriate E85 Hondata FlashPro CANFlex basemap, and fill up with some E85. If you have a CVT transmission, torque gains will be limited to ensure transmission reliability. If you have a manual transmission and want even more power, a custom tune (higher boost and more aggressive timing) combined with other bolt-on parts can easily push you past the advertised gains. Keep in mind that the Hondata FlashPro CANFlex basemaps are deliberately conservative, designed with maximum reliability in mind. If you get a custom tune, you will find that you will not see much power gains going over 30-50% or so ethanol in your tank. However, as mentioned, a Hondata CANFlex basemap will offer better reliability as it is conservative enough to account for sensor inaccuracy and uses a bit more E85 for any given power level, so your engine and turbo will operate cooler.

Installation Info: This product requires a Race Hondata FlashPro. It will not work with the blue CARB Compliant / Exempt FlashPro. It does cannot work with other tuning solutions. To experience the power gains of this product, you will also need access to E85 fuel.

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