Knocksense
 

Anyone using this product?
http://www.viatrack.ca/

talk to medysin he was gonna try that i dont see him around to much now though.

one of our british friends is using it. i probably should do it, just don't feel like spending $100 right now.

My friend has it on his car right now. It's a very professional piece, main issue is getting it "tuned' correctly. Tuning the knock threshold is a little difficult, we just need to buy some serious race gas, tune it so it never goes off with that, and then once we put in pump gas, if we see it light up, then we know we have knock.

Interesting.
I'm trying to figure out all the mods/options that i'm ever going to want to use MS for and i know I want a knock sensor. I hate taking the MS out of my car and figure i should finish all my mods in one whack. That includes: Boost Control, Launch Control, EGT, Knock, GM IAT and heck i might even decide on one more thing but we'll see.

You could always build the circuit on the MSnS-extra site:
http://megasquirt.sourceforge.net/extra/knock.html

Reverant is running it with success. I've got all the parts to build it but I'm not motivated at the moment.

That kind of seems like an assbackwards way of doing it. The easier way would be to determine what is NOT knock. The way you plan to go about it sounds like a recipe for a cooked engine.

Run the car to redline with out going into boost, any events you record SHOULDN'T be knock but regular drivetrain noise. Set the thershold of your device accordingly.

Your Miata has a knock sensor from the factory, use that instead. :)

Jim

Didn't think it would work with MS. I'll look into it.
Or i could ask you. What do i need to do to use it? Build that circuit?

bless he strong Pound ;) cost me not a lot, In fact it'd cost about the same to buy all the components to build the MS curcuit..... as a bonus the Knocksense unit has better filtering built in.

I like it, though tuning it has been a bit of a ball ache, it's still not 100% :(

Yes. :)

Jim

Where is the knock sensor located on a 2000 motor?

-Mike

Thanks.
Could I also use just the knocksense circuit and then hook it up to my stock sensor? Seeing how the knocksense is premade, in a nice box and as said before, better filtered. I think it would just be easier/cleaner for me to go that route.

Right next to the oil pressure sending unit on the right side of the block.

I don't think you would have any problem doing that.

Jim

I'll contact them and see what they say. That would be awesome if that setup worked.
Are you just datalogging knock or do you have it acting when it hears knock as in pulling more timing?

I'm retarding automatically as well, 2* on the first knock, 1* for each subsequent knock, 5* max. I'm running N/A 10:1 and if I fail to get 100 octane gas, it pings at certain RPM zones, mostly between 2000-4000.

Jim

Really? at that AFR and whilst n/a? are you sure it's not just engine noise that the knock sensor is picking up?

Is that 100 octane north American or European standard? There is a difference I believe.

I run 91 octane on my stock 2004 and I think I have noticed some ping under certain conditions as well, kind of makes me worried about going with MS and a DIY turbo setup. This knock sensor is a must.

What timing curve you using Jim?

I know the NB are more knock prone due to the higher compression ratio, but still you must be running extremely aggressive advance mate.

As a indication, last summer i was running at 6psi without IC or WI, at 14btdc and using the stock timing curve.
And i was using normal petrol.

It's also very strange that your getting knock at THAT low a revs.

I've seen and played with various FI's and N/A 5's and i've never seen one knock below 4000rpm.
Nearly every single one starts knocking around peak torque (4200rpm).

If it was me i'd retard the timing a bit and see if it still knocks, as Richy say's it might just be engine noise.



Cheers
Mark

It's 100 European. Me thinks something like R+M/2. Basically 96 "US spec".

Jim

Hi mate,

how about a visit to the club today (its Wednesday, remember?). It mostly pings when the engine is very hot (ie 40 minutes in traffic do wonders), I use 95 octane gas and I try to park with quick throttle stubs in the 1000-2500rpm zone (I can hear it ping). It doesn't ping with 100 octane at all. This is what my spark map looks like right now. I scored +5hp peak hp with this table over the stocker, no pinging on the dyno.

Jim

10:1 refers to the compression ratio, not the AFR. :)
My AFR is basically flat at 12.5 above 5000rpm.

Jim

If your gonna be there and your willing to put up speaking English :o
I'll try me best mate :)

Just looked at my timing curve on a EMU, granted the EMU timing log isn't particularly accurate but it's all i got.

Your timing seem to be roughly what i'm running at 11psi with stock petrol.

So sth seems a bit off somewhere mate.

I have no idea how the Knocksense works, but i have found with the Knock Link it's impossible to get a consistent result.

Either it works great before 5000rpm but then activates from shear noise after that.
Or it doesn't activate at all below 5000rpm but only above.

When i first fitted my EMU i was messing about with the settings and i accidentally added a shit load of timing, i still didn't get any knock without load.

I'll try and get over tonight and we can have a chat about it mate.



Cheers
Mark

So you are running 95 octane? Weird.
Anywho, looking forward to talking to you tonight. As usual, English or Greek, it's not a problem to me. :)

Jim

To be honest mate, i've tried the BP and Shell high octane fuels, but found they are extremly inconsistent.

I'll get a good tank full and will be able to run a couple of degrees more timing, i then fill up from exactly the same petrol station 3 days later and i start getting knock.
So it's retard 2 degrees again.

I've tried several petrol stations around my home and the airport, but they're all the same.

I usually try and chuck in a BP ultimate or Shell optimax every 3rd tank full or so now, just to see if it's improved.

From what i can gather petrol losses octane while its sat in the storage tank, i can't remember what the figures were but it was sth like it dropped 1 octane per week or sth like that.

Only thing i can think of is either ALL the petrol stations are diluting the high octane fuels.
They aren't cleaning the tanks out correctly.
Or the high octane is used that rarely it sitys in the tank for ages and effectively goes off.

Oddly it's only in Greece as well, Italy, France, Spain, Germany, UK etc, the car feels great on the high octane stuff.


Cheers
Mark

Try the EKO 100Speed. I have a friend who has an EKO petrol station in Gerakas. He got tested by the ministry a couple of weeks ago and his 100 gas was analysed as 101.3 octanes.

Jim

hmmm.

:o

Bit far to travel though from Illoupoli though mate.

Well i went along, print outs in hand but no Dimitris.

Still it's always great to talk cars with a great bunch of guys :)

You off to the track day/night coming up?



Cheers
Mark

I came albeit a little late (9ish). Sorry about that. :( It was my birthday yesterday so there were a few things going on in the house. And of course I'll be all over that trackday. ;)

Jim

Happy birthday :)

i tried using my charming influence and take advantage of that great Greek hospitality to wiggle my way into the trackday without being a member, but it was not to be :(


Cheers
Mark

Who all is using knocksense now?
I know scott has it now but are any other MS users using it, PNP or not?

i have one

scott sold his like a week after installing it. id buy one, but i just dislike that it isnt specifically made for the miata. Would be cool to have some sort of unit that could record the "sound" of a na motor on a good tune from 0-redline that way it would actually have something to compare against on the entire rev range.

Wonder if I could turn something like that into a senior design project... It would be so cool to be able to record the sound of any motor like that. The reponses of the sensor would be much more reliable even at high rpm.

Think i'm gonna get it.
I'm redoing my MS setup. Adding a GM IAT versus the stock sensor, EBC, KS now with the stock sensor. Still waiting on ECU pins so I can do up my patch harness to replace the current switch box setup. Gonna run some dedicated grounds for the MS and WB. I'd really like to get some kind of gauge panel like a megaview but I think i'm just gonna mount the palm for the time being. I need to get a oil temp gauge and setup an oil cooler while i'm in the groove.

Reading msefi.com, it seems that many people have problems with false knocks being reported, to the point that the KS is useless. For all I know, those folks were running soild lifters and gear drives. Any MS folks have experience with false reports on our sewing machine smooth motors?

I have solid lifters on my '99, i need to respec the shims on them because they sound like dirty hydraulics sometimes.
'99-00 were stock with solid lifters.

The TurboXS Knocklite does that, to set it you basically have 3 rpm points, tickover, half of redline just before redline.
You then put it into learn mode and select all 3 of these job done :)

Maybe someone could use the LED output as a signal for MS?

http://www.turboxs.com/more_info.php?ID=212



Cheers
Mark

Can you hook up two knock sensors 1 between cylinder 1 and 2 and the other between 3 and 4? Probably extraneous crap, but just curious...

What are the mainstream knock sensors if you dont like or want the knocksense?

(I need to start a new thread and need to do an initial post before it would let me, here it is..)

Håkan

Yes you can do dual knock sensors, but it won't keep the signal seperated. It would combine them. For two different signals you would want two knocksenses.


The knocksense works great with the stock '99 sensor, not to noisy or anything, very happy with it.

What kind of set up do you have for knocksense? I've been trying to get MS2E to work with the stock sensor but so far it hasn't picked up anything. I think I had the threshold too far off, though. I have 2v as the normal sensor output and anything below 1.75v (was 1.5v until Sunday) as a knock. Retards after 2 detections.

My timing is too far advanced so with hot intake temps I should occasionally see some retard in the logs but w/ a 1.5v threshold I saw nothing.

Sweet. I'll add that to my list of things to include in my set-up.

Truthfully don't know anything about threshholds and whatnot. For MSI you have to use a particular circuit which comes prepackaged and tuned here http://www.viatrack.ca/ I bought that and wired it up. Then all you do is set the amount of ignition retard it sees on knock events. Outside of that I don't know what to tell you though. If there is something else I can help with let me know, i guess MSI isn't quite as refined.

That's funny. To get those numbers I set an O-scope on single capture and hit my engine block with a hammer. That didn't seem very refined. :)

Hell yeah, git r dun. hahahaha
I wish I had a scope so I could check some things out someday. Wonder if one of those USB ones would be work alright.