Official OpenFlash Tablet FA20 Tuning Tech Discussion Thread

[Luckrider]

This is because the factory wideband has not been rescaled for the e85. It reads stoich and converts. Read the AFR as gas numbers.

[TruRace]

Originally Posted by Luckrider

This is because the factory wideband has not been rescaled for the e85. It reads stoich and converts. Read the AFR as gas numbers.

The readings on that dyno are from a sniffer on the exhuast, not from the factory wideband.

[Luckrider]

Do you have any logs. That just doesn't sound right at all. If that were the case, you would have about 50% less fuel in the combustion stroke than you need.

[AdrianG]

@TruRace do you have cats in your exhaust?

- AdrianG

[TruRace]

Originally Posted by Luckrider

Do you have any logs. That just doesn't sound right at all. If that were the case, you would have about 50% less fuel in the combustion stroke than you need.

Yeah that's why I am a little concerned. I checked the tune I was running and it is definitely the Stage 2 E85 EL tune. I don't have any logs right now I can take one after I get off work.

Originally Posted by AdrianG

@TruRace do you have cats in your exhaust?

- AdrianG

Yes, both of them.

[AdrianG]

Then the sniffer can't really be trusted...

- AdrianG

[Shiv@Openflash]

O2 sensors read oxygen content, not AFR. They assume you are running gasoline which is why you see a gasoline appropriate AFR. In reality, your actual AFR is a lot lower since you are running E85. Nothing to worry about. Your dyno operator doesn't understand this

Cheers
Shiv

[stefmiesterb]

I noticed the power blocks from crawford for sale on the OFT site. What are the numbers for this product paired with the and open flash tune and OFH/UEL compared to without the blocks?

Is it just the 10whp in the specific RPM range as claimed on the site?

[TruRace]

Originally Posted by shiv@vishnu

O2 sensors read oxygen content, not AFR. They assume you are running gasoline which is why you see a gasoline appropriate AFR. In reality, your actual AFR is a lot lower since you are running E85. Nothing to worry about. Your dyno operator doesn't understand this.

So are you suggesting the sniffer that was used wasn't calibrated for e85?

[Td-d]

Originally Posted by TruRace

So are you suggesting the sniffer that was used wasn't calibrated for e85?

Calibrating it for E85 is not necessary - O2 sensors read in lamba, with the value 1 being stoich. Stoichometric AFR for gas is 14.7, for E85 it's 9.765.

So when the dyno tuner is tuning for an AFR of 14.7, he's tuning for lambda = 1 (in other words, a true 9.765 AFR for E85). It will not affect the process.

See here for interesting data on various fuel types:
http://ethanolpro.tripod.com/id213.html

[steve99]

Originally Posted by mightyt73

I am currently using the OFT ots stage 1 tune. Earlier this week my advanced multiplier dropped down to .8 and slowly made its way back up to 1. Is this normal for the off the shelf tunes?

What fuel are you using on 91 USA fuel this will be quite normal it will do that on stock tune as well. On 93 or better it should not happen.

[Lytheum]

Originally Posted by steve99

What fuel are you using on 91 USA fuel this will be quite normal it will do that on stock tune as well. On 93 or better it should not happen.

Mine still drops on 93 from time to time.

[steve99]

Originally Posted by Lytheum

Mine still drops on 93 from time to time.

These cars really need good fuel at 12.5:1 compression ratio. Even different brands and formulations of fuel can make a difference. you could try different brands of fuel

The problem area is generally between 2000-3500 rpm when you get on the throttle in a high gear.

The stock tune is even worse in this area.


have a read here our 98 RON is supposed to be equal to your 93 but it not quite as good

http://www.ft86club.com/forums/showthread.php?t=61820

[mightyt73]

Originally Posted by steve99

These cars really need good fuel at 12.5:1 compression ratio. Even different brands and formulations of fuel can make a difference. you could try different brands of fuel

The problem area is generally between 2000-3500 rpm when you get on the throttle in a high gear.

The stock tune is even worse in this area.


have a read here our 98 RON is supposed to be equal to your 93 but it not quite as good

http://www.ft86club.com/forums/showthread.php?t=61820

I use 93 from Exxon. Maybe I will try a different station. I'm guessing as long as it doesn't happen a lot I will be fine?