Ok, so I have come to the conclusion that the best way I know to test for pinging is to get up around 60-70 mph and get hard enough into the throttle to get the boost way up there, but just before the truck downshifts. During that time, if my tune was causing detonation, I would hear a few little pings for just a brief moment. I have heard it, been retuned and it went away -- I think.

So my question is this. Durning this test, what else do you hear? Can valve noises be heard? Cam rotation on the lobes or anthing else? Or is it the case that you should literally hear nothing but the blower whine and the exhaust and no amount of "engine noise" when doing this little test? Is it possible to hear a little bit of chatter from the componentry?

Thanks for the input...

Ken

 

Sorry Ken but I've never heard any pinging with mine. I'd be surprised if you could hear it but it sounds like marbles rattling around in a can???

Dan

 

I know the sound of pinging, but I was wondering if pinging is occurring at lesser levels that can't be heard... IF that is the case then any little noise under the hood might be a ping and "listening" for pinging is only to determine if it is bad pinging...

Ken

 

If its doing it up top, it has to be down low too just to much other noise for you to hear it.... I'd go less aggressive on the chip!

Those few extra HP aren't worth venting your block are they?

Also you can pull your plug(s) and look for "signs" of problems, look in my gallery to see what just a VERY little bit of pinging very few times will do.

Just my .02
Johnie

 

I'm not hearing it any more. I had it reburned.

Thanks for the input...

Someone really needs to come out with a reliable knock sensor for this engine...

 

Do the injectors make any sounds?

 

Ford says our engs. are "too noisy" for knock sensors to be effective.

Yes, the f/injs. make a 'tapping' noise but you should be able to isolate that noise with a hose or piece of rubber tubing held to the f/inj. while the eng. is idling.

Dan

 

Knock sensors are definately not the answer to detect/deter detonation. The mod motors are a very noisy line of engines, and the knock sensors have proven to be more of a hinderence, than a savior, when it comes to racing and performance.

The knock sensors have been the culprits in downgraded performance due to the sensors picking up external noises, and pulling timing, making the engines fall on the heavy faces.

Case in point: 99 Cobra, was having spark/timing issues, on each shift, causing the car to stumble and lose performance. Issue was the knock sensors were detecting the noise on every shift, from the transmission, throught the drivetrain. The knock sensors then, through the very function, were pulling timing and causing a loss of performance.

The only solution is a good tune. Not a mail-order, off the shelf tune. Reliable gas, a good tune, and you will have greater chances of a trouble-free engine.

JMO.
joe

 

Pinging won't necessarily only happen down low when occuring up top. The A/F ratio (because of the temperature) and the timing (because of the pressure and temperature) will affect the pinging. When those values are being pulled from a table, each individual table value could cause or eliminate pinging. Engine speed also plays a role because at slower speeds there in more time to ping.

On my hot side of the chip I can't here any pinging in 1st or 2nd but it starts after the shift to 3rd where the load is high and the engine speed is the lowest. On a high speed engine, it can be impossible to make the engine knock. There is simply not enough time.

 

There is also such a thing as "inaudible detonation". Just an FYI.

joe

 

Absolutely. In fact, knock is much harder the hear and much more damaging to a supercharged engine. That is one reason why the stock tune is so conservative.

 

New technologies like in-cylinder pressure transducers and devices which check the feedback from the spark wires are just around the corner. Much more accurate than accoustic knock sensors.