Jump to content
SAU Community

Recommended Posts

When using Knock monitoring systems you need to input a frequency to monitor use this guide as a starting point. I often get called and asked what starting point to use as it is not something that is easy to find in any literature, i have put together a list of my starting points for a few different engines.

If the engine is not listed just ask and i will add it to the list (only takes a few minutes to work it out).

RB20 7.3khz

RB25 6.7khz

RB26 6.7khz

RB26 (forged) 6.6khz

RB28 6.6khz

RB30 6.7khz

RB30 (forged) 6.6khz

VG30 6.6khz

VR38 6.0khz

VR38 (4l) 6.0khz

VQ20 7.5khz

VQ30 6.2khz

VQ35 6.0khz

SR20 6.7khz

SR20 (2.2l) 6.6khz

SR20 (2.35l) 6.3khz

CA18 6.9khz

2JZ 6.7khz

2JZ (forged) 6.6khz

2JZ (3.4l) 6.6khz

1JZ 6.7khz

B16A 7.1khz

LS1 5.8khz

LS2 5.7khz

XR6T 6.2khz

XR8 (modular) 6.4khz

RB20 Forged, and RB20DE+t Forged. How do you work it out? just get it to knock at a low load with the kmon?

Slight off topic question, can you run the kmon from aux power? or will it only work from the laptop?

RB20 Forged, and RB20DE+t Forged. How do you work it out? just get it to knock at a low load with the kmon?

Slight off topic question, can you run the kmon from aux power? or will it only work from the laptop?

Its more to do with bore size, if you look @ the specs you will notice most jap 6 inline cyls are close as they all run around the 86-87mm bore.

There is much more to it than just bore size as many things can skew the optimal frequency but this guide will get you close enough.

I'm pretty sure yo could use a usb charger to run it.... i will ask ray @ gizzmo for you.

what about the frequency bandwidth? care to explain a bit about this option? what is it for what does it do?

The first post above is made to centre the frequency @ an approximate target. The bandwidth control is then used to determines how far above and below the centre frequency the device will detect, i.e. the width or spread of frequencies.

A narrow bandwidth adjustment is very specific, useful for accurately accentuating a specific knock frequency (if you know it). Narrow bandwidth adjustments tend to have less noise.

A broader bandwidth allows more frequencies to be heard, useful for a new set-up where the actual frequency is not known or for initial testing and finding the correct centre frequency. Broader adjustments tend to have more "noise".

There is no correct Bandwidth per see but the narrower the bandwidth the less feedback or noise will be recorded or heard. Nice for loose or noisy solid cammed type engines that naturally emit lots of mechanical noise.

Below is a diagram:

Yellow vertical line is the centre frequency (in this case 6khz)

Red horizontal line is narrow bandwidth

Green horizontal line is broad bandwidth

6khzbandwith.jpg

  • 2 years later...
  • 1 month later...

In addition to the above, has anyone got the kmon to log using fc datalogit? The manual didnt include the designation of the three wires ???

post on the facebook gizzmo page the owner ray will reply quite quickly, i cant remember the wiring. its just a 0-5v output.
  • 3 years later...
1 hour ago, MagicMikeZ32 said:

Surprised you don't have the formula saved on your laptop? Of course understanding this just puts you in the ballpark....

 

=900000/(3.14*0.5*bore diam)

among 1000s of others like crank degrees to ms etc... but its a 2sec reference here instead of trolling through pages of spreadsheets :P

On 07/12/2016 at 3:25 PM, 89CAL said:

HP Officejet Pro? Sounds like an awful ECU

haha but an awesome wifi printer for quick screen grabs for customers

  • Like 1

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I know why it happened and I’m embarrassed to say but I was testing the polarity of one of the led bulb to see which side was positive with a 12v battery and that’s when it decided to fry hoping I didn’t damage anything else
    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
×
×
  • Create New...