After knock destroying 1 motor i'm a bit paranoid now.

But i think even with a kick ass ECU like the Hydra it's still useful to have an indication that knock is/was occurring.

Ok things like failing fuel pump can be picked up by your WB O2 gauge, but the 2 bad tanks of fuel i had were reading ok on the Zeitronix, yet the car was knocking like Pamela Andersons tits at an aerobics class.


It also probably seems that i'm exaggerating in singing the praise of the Knocklite.
There were a few saying that on the mx5nutz forum i'm usually on, after they'd bought one and tried it though pretty much everyone else has agreed.

It is THAT good.

If the electronic whizz's among you can sort out some sort of knock signal from the Dtec-FC wire i recon it'll be even better though.



Cheers
Mark

Great feedback, thanks Mark!

I work with a bunch of FPGA and DSP programmers. Might be a good side project to build a knock sensor processor, especially since they're working on gunfire detection. I'm sure the principal would be quite similar. I'll talk to them on Monday and see if they're interested.

Well, I have an answer, albeit somewhat unscientific.

I increased the sensitivity of my KSMS somewhat and went for a drive. Under light throttle, the LED remains off all the way to redline. Under heavy throttle, the light comes on at about 3,000 RPM and stays on. The engine is not knocking.

So there is definitely a strong correlation between load and ambient noise as perceived by the knock sensor. There may be some correlation with RPM, however I believe load to be the most direct factor.

That kinda nixes the perceived advantage of the TurboXS unit (RPM-based sensitivity adjustment). I still like the user interface and the ease of configuration of the Phormula unit. Just wish there were some pre-built solution out there which actually did a decent job of this. Perhaps one of the current projects will bear fruit. DSP analysis is just out of my league...

I've seen the same unscientific results using my phormula knock pro and KS-3. The KS-3 only has a frequency filter and gain to adjust for noise. I set it up listening to knock using the knock pro and noise canceling headphones.
I do believe that there is correlation a correlation between noise and BOTH RPM and load. I had my KS-3 setup with the warning set, but then I raised the boost from 12psi to 14psi and the warning got triggered. I was listening to knock using the headphones but I definitely don't hear any knock. I guess the only way to tune any of these knock sensors (KS3, KS4, knock light, etc) is to actually use an audible knock sensor and headphones.

From what I've been looking at, there is correlation. The frequencies shift with RPM and load and load increases amplitude as well. It seems linear, which is why I think I can create a DSP program and all you need to do is run up to redline without knock, then let off the gas and go all the way back down. The DSP should be able to learn the range and slope of the change in frequency and I'm hoping to be able to count the ignition events so it can tell what RPM you are at, though it's probably not needed, it would make some of the formula easier. Once you train it, you should never have to touch it and it should work nearly 100%. I'm still trying to find a DSP guy to help me out. The one I had in mind is too busy, but he volunteered a good amount of information to help me out.

I'm still wondering how many people care about this project, though. If it's not very many, it's not really worth my effort.

With Christmas right around the corner I don't really have the dough to spend anything extra on the miata......well, beside the new mani and dp from ARTech. ;) Since my dyno day and posting my ign maps I've been paranoid listening to every sound that I think it never made before. The car runs strong, but sometimes I get the shakes when I get on it.

TurboXS knocklight is on the top of the list, when I get back to looking at that list. lol

not that in this day and age it would be worth it, but you could go to the junkyard and find a saab 1986- 1993 900 turbo or 1986- 1989 9000 turbo and rob the "APC system" out of it.
its old, but works well, is tunable and supports a knock light. its more or less a standalone system and volvo owners have been doing it for years....

Hi there, I'm a new member on this forum.
First, excuse my english writing (I'm a french guy from Quebec city, Quebec, Canada)

I recently bought a 1999 miata with some goodies on it.
Here's the list :
ajustable Blistein coil over suspension with 585 pd/in springs
oversised rear sway bar with aftermarket links
performance breaks
BRP supercharger running boost between 9 et 10
front mount intercooler
clutch ACT
Borla Exhaust (axle back)
walbro gaz pum
one additionnal injector with its controler
power card system from JR

I only drove it a couple hours before I stored it for winter season.
Winter will be a long wait.

I'll put it on dyno next spring.
But before that, I want to install the turboXS (shift/knock) light and the WB O2 gauge I already have in hand (removed them from my subaru rally car).

I have a lot of difficulties to find ecu pin out for my 1999 miata.

Can someone help me to find that and/or provide me with the pinout connections I should use to set it up ? (for rpm and knock if from ecu signal)

Can the turbo XS can be connect directly to the knock signal from the stock knock sensor wire of the car ? Or is it better to install an independent knock sensor like a Bosh one ?

Sorry for all those questions.
I'm new in the miata world.

Here are the installation instructions for the TurboXS KnockLite: http://www.turboxs.com/uploaded_images/558.pdf

The diagram on page 2 indicates that the unit can connect to a factory sensor.

On the '99 Miata, the knock sensor goes into the ECU on a shielded white wire at position 2F. The RPM signal comes out of the ECU on pin 2K, a green / orange wire.

Here is a diagram of the ECU connector:

http://img02.imagefra.me/img/img02/2...4m_3ac8919.gif

WOW Thank's a lot.

Exactly what I was looking for.

May be another question.

I read that some of you used "det can" to adjust the turboXS knock ligth.

I asume det is for detonation but can you explain more about what's a "det can" and how to use it to adjust the kncok ligth ?

Thank's in advance.