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That's not what catalytic converters are for at all. And I've tested my same car with and without catalytic converters, I assure you, they have no effect on AFR.
Let's hear what you think they're used for?

If the sole purpose of the converter was to change then afr then why is the wideband 02 installed before it? Converters are there to do just that, convert gasses into less harmful gasses for the environment. Take a little read if you will, How do catalytic converters work? - Explain that Stuff better explanes how this works. As for afr your primary 02 in modern cars (most fuel injected vehicles) the primary 02 sensor(s) are factory wideband afr sensors that are constantly measuring the afr and making adjustments as needed. Do a little more reading. Youd be enlightened by what you may find.
A WBO2 is installed before the converter(s) because the converters alter AFR / reduce harmful emissions. When you install a WBO2 after the cats (which is the wrong way, hence why you never see anyone doing it that way) you're getting a reading that isn't accurate at the engine because the cats (if working correctly) are doing their jobs and reducing harmful emissions / attempting to reach the stoich ratio. When tuning accurately you want to know what the engine is doing AT the engine and not anything behind that where the AFR is changed.

The reason you have an O2 before a cat and after cat is to ensure the converter is working. If the converter didn't do anything why would you even need a 2nd O2...

If anyone needs to read anything you need to read this...

EFI University Electronic Fuel Injection Tuning :: View topic - Do catalytic converters affect AFR?

http://www.hptuners.com/forum/showthread.php?24124-do-cats-affect-AFR

Will the every day driver notice a difference in a tune done pre / post cat? Probably not especially at idle or normal driving. WOT is a different story. My point was why do all this tuning work on a value that isn't at the engine.
 

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Discussion Starter · #22 ·
https://en.wikipedia.org/wiki/Catalytic_converter

What is a catalytic converter and how does it work? - HowStuffWorks


Carbon monoxide is a poison for any air-breathing animal. Nitrogen oxides lead to smog and acid rain, and hydrocarbonsproduce smog.
In a catalytic converter, the catalyst (in the form of platinum and palladium) is coated onto a ceramic honeycomb or ceramic beads that are housed in a muffler-like package attached to the exhaust pipe. The catalyst helps to convert carbon monoxide into carbon dioxide. It converts the hydrocarbons into carbon dioxide and water. It also converts the nitrogen oxides back into nitrogen and oxygen.
 

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Discussion Starter · #23 ·
Again- I have done wideband testing PRE and POST and I can assure you, they are the same readings. I've done testing on my cars with and without catalytic converters, and again, the AFR is the same either way at the tip. If you have an exhaust leak or something, it will throw it off for sure.
 

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Well I'm ready for the details on this kit already.
 

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Have friends and kids with flex-fuel vehicles and with E-85 around here. Same old story, for fuel economy, cost more per mile than paying a little extra for real gas.

But performance was not an issue with them and neither was being "green".

So gathering if you want performance or being green, get this kit. Wonder what the price of E-85 would be if the government wasn't subsidizing it.

Ha, like asking stupid questions like why E-85, why not E-100?

Here is a bit on E-85, but a bit difficult to learn the BTU and octane rating, and really don't know what's at the pump with over 18 manufacturers of this stuff in Wisconsin

"
[h=1]E85 Specification[/h] ASTM International developed a specification for gasoline-ethanol blends containing 51%-83% ethanol that address proper vehicle starting, operation, and safety in varying temperature conditions. The table below shows the requirements of the ASTM D5798 Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines. Fuel retailers or fleets purchasing E85 should specify meeting the requirements of the specification as a condition in their supply contracts, so that they can guarantee their product is ASTM-compliant.
Like gasoline and diesel fuel, E85 and other ethanol-gasoline blends are adjusted seasonally and geographically to ensure proper starting and performance. For example, E85 sold during colder months often contain lower levels of ethanol to produce the vapor pressure necessary for starting in cold temperatures. For this reason, fueling site operators offering ethanol blends typically cannot carryover summer-blend E85 into the winter months. They must instead "blend down" any remaining summer fuel to meet the ASTM specification’s requirements for winter temperature conditions. This can be done with relative ease by adding additional gasoline to the storage tank. On the other hand, there is no concern with carrying over winter fuel into the summer months because flexible fuel vehicles can operate on any blend of ethanol and gasoline in warm weather. For retail service stations, seasonal fuel adjustments are handled automatically at the wholesale fuel terminal."

From

Alternative Fuels Data Center: E85 Specification
 

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Discussion Starter · #27 ·
Kit will be available for retail purchase later this week. If you are interested in buying NOW, just shoot me a PM.
 

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Almost been a month.
Kit is not available yet and old kit was removed.
Out of stock on injectors too. :/

Questions.
Is old kit discontinued entirely?
Is the new kit still available with trifecta goodies for people who wanna jump from stock straight into e85.
And final question, for those of us who will have little to no issue finding e85 within 1 mile of any location. What's the price difference between the old and new kit?
 

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Discussion Starter · #29 ·
These kits are available on our website as of last week
 

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On your website it says it wont fit a 2011 cruze. Why is that?
2011 ECUs on the LUJ did not have stock Flex Fuel mappings in the ECU. Can't tune what is not there. 2012+ ECUs with the LUJ motors had Flex Fuel mappings built into the E78 ECUs, but GM chose to never sell them as Flex Vehicles therefore never installed the fuel sensor which is what this kit is selling.

Also E85 is higher octane but it is also less BTU/#. So that is why you have to to larger injectors b/c the engine needs more #s of fuel for #s of air. AFR will be the same, but you will burn more volume of fuel.

In short E85 is cheaper bc it has lower fuel value aka potential energy when burned. You will likely not see much saving unless the price disperity is huge, but you do get to compare it to race fuel prices 105-108 octanes.
 

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I'm not into cars enough to do this on my own. Could this be done by a mechanic or dealership? I was thinking why the Cruze didn't come with flexfuel as even the cars "under" the Cruze has the flexfuel option. Also I've seen flexfuel for some cars offer less MPG
 

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I had a rental Taurus with the flex fuel option. I ran one tank regular fuel and the other on E85 running down the highway. When you figured in the cost per mile, it was actually cheaper running plain old gasoline.
Depending on the car, E85 needs to be 2/3-3/4 the price of gas to actually be economical.

When your rental is flex fuel, and you get fined for failing to return it with a full tank, fill it up with E85 just before you drop it off.
 

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Discussion Starter · #35 ·
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