ChrisJ951

Are you going to build a few and sell them?

Tom M'Guinn

Yeah, but it's nice to have two big digital read-outs. Haven't fully settled on where to put it (or what size LCD to use). For now, it's where the ashtray was.

KLR Pin 18 goes into a voltage follower then directly to an interrupt pin on the Arduino. The Arduino sends it a square pulse long to the Zeitronix for each knock, long enough for the Zeitronix to log.

Once I'm happy with the code and functionality I'd be happy to share for hardcore DIYers, but not planning to mfg and sell any per se. I'm no engineer, and suspect real software folks and EE's would cringe at the code and supporting circuits....

Crazy Eddie

Yea, I am really going to cringe ... NOT !!

DDP

Very cool project, Tom. The Arduino really opens up so many doors in a such a cheap and easy way. Are you powering it with batteries or did you hard wire it into the car?

I'm not 100% familiar with how the KLR senses knock, but do you have any way to adjust the sensitivity of reading the knock? In other words, do you have any way to adjust what you define as knock? Or is it simply what the KLR determines to be knock?

Tom M'Guinn

It is wired to the car's 12v system. The KLR has a "yes/no" output to indicate when knock was detected and the counter simply counts each yes event. The signal is very short and there is lots of noise in the system from the ignition, etc., so even counting the "yes" signals involves some interpretation. I've worked to replicate what the Curtis counter considers a trigger so that the results are comparable to other people's cars, but the arduino interrupt function is so much faster than the Curtis, you can see that the Curtis counter isn't necessarily a perfectly accurate interpretation of what the KLR is trying to say...

Meine44

Tom,


Have you finished a write up on this system yet?

Tom M'Guinn

If memory serves, I got it to the point where it replicated the Curtis counter pretty closely, but never installed it because Vitesse came out with V-Knock, which does essentially the same thing (and more) in a much smaller unit. V-Knock doesn't have the LED gauge, but that was never my real goal -- I just wanted to log knock so I could separate WOT from other knock and see where in the map it knock was occurring. (And, if you were so inclined, adding an Arduino based LED display to the V-Knock would be a snap...) I'm working on a semi-related thing now (to monitor/display/log actual ignition advance and detect when the KLR is pulling timing) so may work on updating my write-ups when I'm done with that.

Meine44

Actually, the reason I was asking is because I plan on installing V-knock, but I will not have a data logger installed any time soon (other projects are taking up my wallet space).



I would be very interested in information regarding installing a digital counter/display to the V-knock system.

It would be nice for me to be able to see how many knocks I'm getting while I drive.

I am VERY skeptical of the quality of gas where I live; my county has added emissions regulations, and I can go the county over, but sometimes I get lazy and I want to make sure I'm not doing too much damage.

Tom M'Guinn

Well I have not done it, but seems like you could add a counter/display any number of ways. The Arduino could easily read and display the V-knock outputs, but not sure it would be worth the effort for what you get? The easiest (without DIY arduinos or the like) might be to just run both a Curtis counter and the V-Knock together -- that works fine, I've done it... Logging the signal is much more useful though. Have you looked at the zeitronix Zt-2? It gives you a wideband system (which is very useful) and the ability to log signals from the V-knock (or other signals) -- all for under US$300...

Crazy Eddie

After seeing what the ZT-2 does, and how it works, I would say it's not even a question, as to whether you should buy one ... It's a must !
Spend your money there, before anywhere else ( if you like your car's engine )
Otherwise you are shooting in the dark..
BTW I have the V knock, and its logs to the ZT-2 and its great
Good luck
Regards
Ed

Meine44

I'm planning on going for a Rogue M-tune, and probably using their data logger. I have heard good things about the ZT-2, but I won't have the need for two different loggers.


That being said, I am just looking to get the V-Knock and modify it to display a digital count of how many knocks I'm getting.


I want something that can give me a simple count until I am ready for a full data logging system.

Crazy Eddie

I hear ya
I don't have that system
I have the Vitesse (SMT6) with the V Knock and ZT-2
I believe all that is possible...
Eric https://rennlist.com/forums/members/72025-urg8rb8.html
Has the M-tune and is logging I would ask him

Meine44

I've already bothered him with enough questions!

Meine44

TOM,

I have looked at the ZT-2, but it is not within my budget. I am also not sure I would go that route; I plan on upgrading to M-tune (Rogue) and possibly using Rogue's data logger.


I would purchase a CURTIS counter, but the one commonly used on the 951 is NLA.

Just curious how to wire in an Adruino or similar counter to the V-knock.

Sixline

You can still buy the Curtis Counter in the link below.

http://www.digikey.com/product-searc...FUx95Qod-xgd_w

I was going to buy one but after seeing this I am going to wait as this looks much cooler.