HOODEY

All I pulled this together and it is specifically designed for the 350z.
You wont find any knock tool out there that is tailored for the 350z.
It even show intake cam advance. Anyone interested please pop me an email.

Using the cam and crank signals it only listens for knock when it is likely to occurs. That is between 10btdc and 40atdc.

The crank and cam information allows the system to choose the right knock sensor or bank to listen in real time.

This information allows the system to determine which bank and which cylinder is knocking in real time.

Knowing knock is good but we also need to know at what rpm and what ignition timing it is occurring. These inputs even allows us to see the cam angle of the intake cam.

As the engine rpm increase so too is the noise level. With only one threshold this has to be set higher than the greatest noise of the engine.

This level may be so high that detonation at low rpm may be missed because this threshold is never breached. Variable sensitivity over rpm allows the threshold to be lowered at lower rpm so that low levels of knock can be detected.

The device can auto learn the noise profile of an engine which is not knocking. This is equivalent of setting multiple thresholds per rpm automatically.

On board is memory which can log all critical values at the onset of detonation.

I am a tuner as well and I was always scared of making ignition timing adjustments. It was like flying blind folded making changes and hoping there where safe. I am made 247whp at the wheels tuning a 1500cc engine. I could have made more but there was nothing to tell me I am going too far. With more expensive engine and greater investment this tool is worth the insurance.

Cux350z

iTrader: (162)

more details on how it connects to car and what is required to install

HOODEY

Connect to both knock sensors and plug into system using standard audio jack.
One connection to crank sensor output.
One connection to bank one intake cam output sensor.
One connection to ignition pulse for cylinder one.

tcode

iTrader: (7)

If you are a real tuner, you shouldn't be afraid of tuning the ignition. Actually, that is the most fun part of the tune process.

I wouldn't rely on any knock listening devices above 5k rpm. There are just too much noise. Instead, use dyno, do small steps in ignition increment and if knock occur, you will see significant drop in power when it happens. Also, pair of trained human ears are good knock listening device too .

Of course, there are devices that are accurate in detecting knock, such as measuring dynamic cylinder pressure and ion currents, but that things are so pricey .

HOODEY

Updated Video showing connections and voice over.

Variable sensitivity over rpm will help at higher rpm once the noise profile without knock is established.

kilogram

iTrader: (1)

Is the OEM ECU really that bad? Every time I've ever heard knock, it's showed up in the knock counter log. I've even watched it increment during a knock event (all this has been at low load).

HOODEY

I have seen many turbo engines fitted factory knock systems blow their engines. I would have thought the factory knock systems would have intervened. May be it did but the tuner continued to put more demands on the engine but never got a distress warning.

http://www.ebay.com/itm/Knock-detonation-detection-monitoring-System-for-350Z-/251746789890?hash=item3a9d472a02&item=251746789890&pt=Motors_Automotive_Tools&vxp=mtr

HOODEY

I believe this uses the same concepts. A bit more refined but look at the price.

myfirstzcar

I'm with tcode on this one, plus there is only one knock sensor.

HOODEY

Trust me.One knock sensor makes it really easy.

The processor has to constantly instruct the knock interface chip which
channel to enable in real time before TDC when there are two knock sensors.

The routine which switches knock channels simply needs to be disabled for the 350z hence defaulting to the users selected knock channel.

Resmarted

iTrader: (2)

If you're tuning near knock, your not doing anything right. Max power is well below the knock threshold. I've seen quite a few instances where cars drop a lot of power before they start knocking.

Besides that, the reason why knock sensors are stupid on vq's is they're very noisy. There's no 100% certain way to differentiate with sound pulses between phantom knock and slight knock.

On lots of engines you can hear knock real easy without knock detection.

myfirstzcar

I can hear my Titan knocking. It did it before Osiris and after. With 2° of added timing, 91 octane, and the throttle restriction removed it still does it.....but with a very noticeable amount of extra vrooooom!

Resmarted

iTrader: (2)

I don't think your stock Titan was knocking.

Especially if adding timing made it run better.

Do you just think it's knocking or did a tuner tell you it was? Knock sounds similar to a small rock in a can "pinging" around.

Here's a great example of Knock lmao:


If you actually think your car is knocking, don't add timing (that's a total dips*** move), and start diagnosing what's going on. In person it can be harder to tell, especially if you haven't heard it before, and you don't know what you're doing lmao

HOODEY

Not totally true.

Resmarted

iTrader: (2)

When knock happens, a tuner will hear it, feel it, or see it on the dyno.

Good tuners don't just throw timing at a car until it starts pinging and then pull back. Maybe on a street tune, but that's just one of many reasons a flat out street tune isn't ideal (although adjusting on the street can be useful).

Besides that, with the rod stroke ratio of these cars watching the timing curve vs the RPM is quite important to having not only a drivable setup, but a car that lasts.

Not all cars have a lot of timing between MTB and knock, but a lot of cars start loosing power before the car starts knocking. Also, watching how quickly knock starts happing can help determine if knock is actually phantom or real.

All in all, there's a good reason why a lot the best tuners don't use knock ears. It's just not necessary in most cases. Although some engines are different than others.

Basically if you're relying on knock ears on a dyno, it's not a good sign of the competency of your tuner imho

HOODEY

Don't want to have a long discussion with you on the merits of knock detection equipment.

However it is not uncommon to reach the knock limit before reaching MBT timing especially on pump gas.


https://plus.google.com/photos/10012...42631003862483

myfirstzcar

So I must be a moron right? How about the guys at Cajun tuning who added 2° and sweetened up the fuel tables? Are they idiots? I know the sound quite well, but it's so faint that my knock sensor is obviously not concerned with it.
In case you haven't ever noticed, a lot of vehicles also make that same sound prior to reaching closed loop.....it's normal to some extent.

Pushing the limits of pre-ignition is a big part of what tuning is all about.

Resmarted

iTrader: (2)

Lol hey it's your motor. Do a compression test in 6 months and tell me what's up.

I've personally seen a single turbo 2jz, an ej25, and an sr20 all ruin rings with "mild knock" in boost load, from street tunes. So if you think it's fine, that's your problem.

myfirstzcar

We're not talking about a boosted 2jz now are we? This VK sounds exactly the same as the others I've driven, and I can see and review everything the engine is doing anyway......which I've already done several times, and so has Joe from Cajun.
What I have now is a stock, tuned, 4 door Titan that will beat any stock 350z all the way to about 70mph.

Conway_160

iTrader: (1)

I doubt that, but hey like to see the races. "Sanctioned Events"