BJai02

iTrader: (5)

I am now thinking my car is running noisier than others. I am not sure if it causes the timing retard being overly sensitive. Is there a way to find out if the default knock value is too high or too low without using a Tuner Pro to listen for the real knocks?

I've never had any audible knocks since the UTEC. It's either my knock sensor was set too sensitive with TurboXS's default value, or the UTEC is really pulling enough timing quick enough before it has any audible knocks.

How does the knock value works? The higher the number, the more sensitive it is?

FWIW, I am runnig 272's with stock valve springs. I am not sure if it contribute to more engine noise at high rpm.

MalibuJack

iTrader: (5)

272's do tend to make a bit more noise, usually the lifters make noise if their not bled on install, which could transmit into the knock sensor..

I don't recall how it was set, I didn't adjust it on the UTEC, but I did set it on the tuner pro so it would indicate a lower threshold.

I think there's a sensitivity setting, and a count setting.. the sensitivity sets the discrimination, and the count sets how many instances before it registers as knock in the logging (and pulls timing) and then theres another setting for what it should do when you do get knock..

Its pretty fast and will pull timing as necessary almost immediately when that light flashes.. but the default settings aren't perfect for every car.. My car is the poster child for the UTEC and the settings seem to work well (if not a little conservative which I prefer) But I do rarely get knock..

If you want to know for sure, you'll have to get an audible detonation phone set.. its basically a piezo microphone that you attach to the engine block somewhere, a small amplifier and headphones.. (something like the knock-link tool, but the knock-link is a visual tool and I don't know if it has a headphone jack on it) I use the Tuner Pro for that..

BJai02

iTrader: (5)

MalibuJack,

I am looking at the manual of UTEC and Tuner Pro, the knock threshold seems to present by a different unit or value. The UTEC default set at 105 at 2000 RPM and down to 33 for 6000+ RPM. The Tuner Pro default at 105 at 2000 RPM and down to only 80 for 6000+ RPM. So I guess the value means something different? And I assume the lower the number means the less sensitive the knock sensor is?

MalibuJack

iTrader: (5)

the higher the number, the less sensitive it should be.. at low RPM's our engines produce alot of racket, mostly valvetrain noise that would trigger the knock retard feature if it wasn't tuned for those RPM Ranges.. (FWIW on the Tuner Pro, unless you hook up the RPM signal input, the only value used is the 2000rpm one..)

basically its just a digital value for a discrimination (filter).. and then a quantity that represents how many times it has to be triggered before its registered as knock.

At 5500rpm, our engines seem to have a resonant harmonic that triggers the UTEC's knock sensor.. Not every car does it, and most of the time its probably mild knock, but just be aware of that.. The Tuner pro's value of 80 is probably because the most convenient location to mount the sensor is on the head, and it needs to be set a little less sensitive to keep from triggering its indicator from the valvetrain, except the tuner pro does nothing but monitor stuff, so you'd likely be listening to the engine while this is happening anyway.

BJai02

iTrader: (5)

Thanks again MalibuJack!
I am really surprise that TurboXS doesn not have this info documented better. It doesn't even explain rather higher or lower numbers representing a more sensitive setting :/

BJai02

iTrader: (5)

To those of you who has an engineer degree, do you know how I can DIY an amplifier the stock knock sensor signal to a headset or speakers? A simple drawing will be good

Thanks in advance!

BJai02

iTrader: (5)

I found myself an answer:
https://www.evolutionm.net/forums/sh...80#post2284780

CBRD

iTrader: (60)

we actually found that our balance shaft was off one tooth, while timing up the car and installing cams recently.

this had to be this way from the factory, as we had never touched this. I am curious to get back to the dyno and retune, because we had a strange knock up top, where the afr's were good and we were at moderate boost... we were thinking an oversensitive knock sensor.

chad b
chadblock.com