5k6

iTrader: (19)

Here is my knock sum at 22psi:
RPM KnockSum
1906.25 0
1906.25 0
1968.75 0
1968.75 0
1968.75 0
2062.5 0
2125 0
2218.75 0
2281.25 0
2375 0
2468.75 0
2500 0
2593.75 0
2656.25 0
2718.75 0
2812.5 0
2937.5 0
3062.5 0
3187.5 0
3312.5 2
3468.75 2
3750 2
3937.5 1
4062.5 1
4187.5 1
4343.75 1
4531.25 0
4687.5 0
4906.25 0
5093.75 0
5281.25 0
5437.5 0
5593.75 0
5750 0
5937.5 0
6125 0
6343.75 0
6531.25 0
6687.5 0
6812.5 0
6937.5 0
7031.25 0
7156.25 0
7250 0
7000 0

4TUN8

iTrader: (18)

If you're running 21-22psi try reducing about 1 degree of timing in the 220-240 load cells at 3500-4500 rpm range.

That is if your afrs look clean and in the range of 11.2-11.6 area

5k6

iTrader: (19)

Did 3 more runs today and put BP 93 in which is what it was tuned on:

5k6

iTrader: (19)

Should I try turning down the boost to like 21?

DynoFlash

iTrader: (91)

What is your boost at now ? It seems the worst of your knock counts is on spool up so maybe the boost is spiking too hard.

I would not suggest more than 21 psi on pump gas given your data logs.

My suggestion - LOWER the boost to 21 psi and try a new tank of gas

If its still knocking and pulling timiong at 3,800 - 4,000 you may need a bit less timing and of more fuel there . . . . but first try lowering the boost and some new fuel

As an aside . . . .

It is normal for the cars to pick up some knock count and pull a degree or two of timing from time to time

In this case - it is clear that the car is pulling timing which is NOT desired

This is what the entire knock control system is set up to do

I think the idea is to tune the car on as reliable and representaive a tank of gas as you can find and set it up so on the road it is not knocking and running clean

On a IX this involves balacing a/f , MIVEC and ignition timing to achive a safe and knock free tune which is stable and repeatable under a wide range of operating conditions

The fact that a car may occassionaly pick up a few knock counts is not cause for alarm as the ecu will adjust and pull timing in response

As a tuner, I am noting that the gas supply in many areas is getting very unreliable and inconsistant

I really feel that we are getting real crap gas in many locations and it is becomming more and more difficult to achive great power numbers that customers demand while keeping the car totally knock free on what ever gas the customer may pick up in varying gas stations

IMHO - one of the features which has always made the stock ecu vastly superior to nthe aftermarket soultions like the utec, hydra, and aem ems is that the stock stock knock control is very good and fast acting. the IX is super senstive to knock and can react the slightest of noise.

zbomb

iTrader: (48)

Al, do you think the the addition of more ethanol into the gas is what is causing the varying conditions lately. Over the past 6 months ethanol is up to 10%, at least on the east coast.Sorryt for the ot.

5k6

iTrader: (19)

Ok thanks Al I will try setting it at 21 psi and do some more runs.

DynoFlash

iTrader: (91)

ifv you can see if you can come by my chicago tuning trip in two weeks I would like to take a look at it

DynoFlash

iTrader: (91)

Off the top of my head . . .

If anything you would expect ethanol to help - however I think when they are adding the ethanol they are using weaker gas to reach the same effective octane rating

The ethanol content would alter the BTU capacity of the fuel - generally a 10% ethanol fuel has 3% less BTU capacity of a normal unleaded gas

This means with the same a/f ratio there is 3% less power with a E10 fuel

When racers use alcohol they run 2 times more alcohol than gas as the ideal burn ratio on alchol is mushc richer than gas - this results in more available BTU than gas

With E10 fuel in your tank you will prob have to run the car slightly richer to make the same power which is why with E10 most vehicles loose fuel economy

I am hoping to do some orgazinzed testing of various pump gas with ethanol and pay more attention to specically what kind of fuel is being used in various areas I travel to in order to further refine my remote base flash tunes

5k6

iTrader: (19)

OK here is one of the runs I did at 21 psi:

5k6

iTrader: (19)

AL I could come by on Monday during or after the 11am slot?

I will be in Oshkosh this weekend (28-30) for the airshow but I could come home early if Monday does not work.

andenbre

iTrader: (4)

most of the chicagoland area is 10% ethanol now

andenbre

iTrader: (4)

hey, another thing to keep in mind is that if those logs are from the last 24-48 hrs we are in the middle of a heat wave here. temps are reaching 100 degrees with very high humidity and that would have an effect on knock esp. at increased boost levels.

5k6

iTrader: (19)

This is true but the runs were done in the night time but I dunno.

DynoFlash

iTrader: (91)

That works fine - it will only take about 15 mins to review your data and determine if it needs a slight adjustment

Try to come with the gas you will normally be using

In the meantime - try lowering the boost to 21 and a new kind of gas and report back what happens