I hear a kind of rattling sound when I go WOT. Recent reading has lead me to believe this may be detonation. Does anyone know what would cause this or how I can confirm?

 

If you here and engine rattle that sounds like rocks in a can...at WOT, this is detonation. To confirm it, put some race fuel in your car. If the knock goes away, it was definately detonation.

What is your setup? If its just the included emanage blue, you have problems that need to be addressed....namely a better EMS that has timing control, and possibly a fuel system upgrade, depending on the boost level you are running.

Please give us some more information about your current setup.

 

I am using the E-Ultimate. I have a Walbro 255 fuel pump. I am retarding the timing starting at -3 at 1 Lb boost and retarding one more degree for each pound of boost. I am making just over 8 lbs at WOT. A/F is good all the way to red-line. I don't have access to race fuel.

 

I used to get a pinging sound when I was running high in the rpms and it sounds like little pebbles hitting a sheet of metal.

 

Try pulling about 10 degress through the trq peak, and see if it goes away. That is another method of checking if its true detonation.

What is your AF ratio at these points?

 

AF ratio at 8 PSI is between 10.5 and 11.0. I am now using the MAP sensor to apply timing adjustments. How do I adjust timing through trq peak? I have been using boost - should I just set -10 correction for all times when boost is above 0?

 

How do you know were is TQ Peak if you don't have a dyno Just look at other Greddy Dyno or yours and see were the TQ peak, it is usually were you hit your Full boost. That is the problem with Emanage, you depend on what the ECU want for timing and you just subtract from it.

Do you have any logs? What was your timing around your knock area? at 8psi you want your timing around 11-13 at tq peak (at least that is what I have). You have to know were you are knocking so you know were to subtract. Just be careful around 3500rpm-4500rpm coz that is where you tend to produce the most TQ.

 

I have a pretty good idea where peak torque is, but how far on each side should I set the timing correction to -10?
Here is one of my first dynos from before I changed my fuel pump...

 

You cant really do any street tuning without a good logging software. find out first were you are knocking and start from there. why is your TQ dipping like that? Is the ECU Pulling some timing? You want your timing the lowest on TQ Peak and gradually add timing as your TQ goes down. pull some timing around 3400-4500rpm and see if that happen.

 

I have great logging software. The E-Ultimate has all of that built in - it just won't show torque because I don't have a sensor for that. I can make a log of timing, boost, RPM... So, I can definitely see what all the parameters are at when the knocking starts and pull timing specifically at those points.

 

Great, so can you post some logs so we can see your timing curve? Your A/F is conservative so it is definitely timing issue. Retarding you timing by 10 (I know Sharif just gave that # for Troubleshooting purposes) can be to much and power will suffer so post your timing and we can help you on how much to pull.

 

I was getting some detonation mid summer out here in Phoenix and yes it does sound like small metal ***** being poured over a tin plate.

But the nice thing about a UTEC is that it will tell you where those spots are and pull timing for you. I went in and pulled out a few degrees of timing in the problem areas and everything was fine.

 

I have gotten some knock based on UTEC but I have never actually heard it. How loud can it be? Can you hear them if you have a loud exhaust or speed over 60mph?

It was funny coz today I thought I actually heard some knocking (metal knocking at each other) but it turn out it was an 18 wheeler truck next to me making that sound

 

OK, I went out and made a few logs. In this one, the item highlighted in the legend is Boost. The red vertical line is the point in time relating to the details in the legend. Unfortunately, you need the Greddy software to allow you to see the scale of each of the items logged, but in this picture, you should be able to get a good idea of what is going on by relating the curve of each item and looking at the legend to see the value at the red vertical line. I selected boost in the legend, so that is the scale displayed to the left.

The red horizontal line is the engine RPM (at 6262 rpm at the vertical red line). The starting RPM on the left was 3200 RPM. Ignition timing is the yellow line - starting at 29.5 degrees and dropping to a minimum of 1.7 at 1.63 seconds on the graph. Timing adjustment is the black line. The flat spots are -10 degrees from stock with the max adjustment at -12 degrees at 9 lbs boost. I had adjusted all cells to -10 deg of timing for boost of 1 to 7 lbs for that run to see if it would stop the knocking sound. I didn't really notice a change.

Here is my timing adjustment map:

 

So if I'm reading it correctly, your timing was between 1.7-8.7 and A/F are from 10.5-11.0 when on boost, then I don't understand why are you still knocking. Do you know which RPM you are knocking? By they way, to much timing retard will raise your EGT.