EdyJun

Well, after studding logs for many months now I have tired to get better timing. It seems that this is the best I can do on my car.

-1.5 deg tming ---GIAC X MBC stand alone - NO TDC -- 62 deg - 95 oct - other ECU -FATS = 4.65:
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image008.gif">

This is what PSmallsSmells gets:
Weather=62F, Gas=3/8ths tank of 93 octane Mobil, Boost=~23 PSI tapering to ~21 PSI:
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage362FTiming.gif">


So, I decided to do some testing on 95 oct gas using Trick 101 oct and SoCal 91 oct to get a blend that is comparable to 93-94 oct gas for the east coast people, keep in mind that we have 91 oct w/ 10% ethanol. My 95 oct blend has some ethanol in it from the 91 SoCal gas.

I decided to go with 95 oct to better match the 93-94 oct of other states (other states do not have ethanol in their gas).

Here are my results: (The Lem settings were the same for all runs, except for less than 1% change in primary, I used 2 different GIAC X ECUs as well as reset the ECU via Vag (soft reset) and pulled the ECU.) I finished 3/4 th of the 95 oct gas by the end of my testing. So about 200 miles total.

page 1 Red - 62 deg - 95 oct - other ECU -FATS = 4.65 - reset ECU
page 2 Pink - 62 deg - 95 oct - other ECU -FATS = 4.59 - reset ECU
page 3 Dark Blue- 66 deg - 95 oct - Edy's ECU -FATS = 4.67 - soft reset (Vag Clear)
page 4 Light Blue - 60 deg - 91 oct - Edy's ECU -FATS = 4.84 - My BEST time on 91 oct

Intake Air Temp:
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image111.gif">


Timing: <b>(You can see that the 95 oct gas has about 5 deg more timing ACROSS THE RPM range than the 91 oct gas)</b>
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image112.gif">


CF:
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image114.gif">

FATS:
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image121.gif">

O2:
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image124.gif">

Injectors Duty Cycle: <b> (91 oct needs about 15% more fuel to sustain about the same power)</b>
<img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image125.gif">


You can find my complete detail logs <a href="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct.htm">here</a>.

<b>My conclusion:
My brew 95 Oct gas has about 5 deg better timing than 91 SoCal gas, and you need ~15% less fuel to sustain the same amount of power.

I think my blend of 95 oct gas is still not as good as other state's 93-94 oct gas since it still has ethanol, but it is the closest I can match to the 93-94 oct gas.

For those that are doing competitive FATS compared to the people that are running these 93-94 oct gas, kudos to you. </b>

Edy

Discussions ON!

EdyJun

<ul><li><a href="https://forums.audiworld.com/s4/msgs/2459283.phtml">I think i am going to ship to you (PSmallsSmells) 5Gal of OUR 91 OCT SoCal gas to see how it will work in your car. - EdyJun</a></li></ul>

jprice@CPS

I'd say that's the primary reason that psmalls gets more timing up top than you.

jprice@CPS

Also, if you're getting 10 degrees CF at 62F, I'd dial back the timing.

EdyJun

I am pulling 1.5 deg of timing right now, do you think i should pull more and why?

Edy

jprice@CPS

So even at 100 degrees F, your CF doesn't get up to 15?

EdyJun

<center><img src="http://homepage.mac.com/edyjun1/S4/Logs/95%20vs%2091%20-%20many%20logs/95%20vs.%2091%20oct_files/image126.gif"></center><p>
BTW, I am on Stock fueling w/ a crushed 4bar. That maybe why.

Look at my log and his log @ 6500 RPM. We almost have the same timing.

Also, look at this log on 91 I am running more fuel so my setup can run more fuel if need to be.

Finally, his timing is just to show how well his car is doing. I can't compare to his since I don't have his setup. However on my setup I get more timing when I run 95 vs 91. Look at 6500RPM on my log and you will see the difference on timing for 91 vs 95.



We need to compare the same setup.

Edy

EdyJun

I would not race or go past 5.5 RPM in 100 Deg, so it would not be important to me.

Edy

EdyJun

By "alcohol injection" do you mean w/i into the Bi-pipe?

jprice@CPS

uhh.. ok.. Do you ever track the car?