I have no idea what det sounds like as most prob a lot of people don't so to me a light sounds the best solution to us mere dummies
I have no idea what det sounds like as most prob a lot of people don't so to me a light sounds the best solution to us mere dummies
this is what the guy said about the knock sensors on ebay for £120.
does this sound right or are they just cheapy bin fodder?
what sort of questions do i need to ask?
Hi,
Once the knock sensor is bolted to the engine block and the KnockAlarm is connected up to that and a 12v ignition source there is no fiddling about or special setup to be carried out. That's it.
It's very simple to install and comes with full instructions, and it's active and listening for knock as soon as you start your engine. It's not rev dependent because knock can happen at low revs as well as high revs so it listens across the whole rev range. Knock happens at a very specific frequency regardless of rpm.
Hope this helps.
that sounds very obvious what to listen for but i wonder if thats how it really soundsOriginally Posted by Tutuur
That has the bass and treble very steeply cut off.
Without audio filtering you hear a sound like you knocked a table with your knuckle. Then if the det is worse you hear more of a crack.
The sound is going to be modified by the size, shape, etc of the head, block, etc. A drumstick hitting a large drum makes a different sound to a very small drum.
then have a look at my homemade knock sensing device thru the radio again:
http://www.youtube.com/watch?feature...&v=yPnDbRZ5Ih0
i have a video where you can hear the knock too but it isn't on the net
how about these the price seems good even though you need to supply a knock sensor but anyone know if these are any good?
http://www.ebay.co.uk/itm/Knock-Sens...3#ht_758wt_932
Thats a good example of a lot of knock, but with a turbo motor you can kill the engine with a lot less knock than that, so you need to be able to hear the onset long before you get to the stage presented in that vid. You will hear infrequent pings of knock before it gets "busy" like in this video. It's also a lot easier to hear it at lower RPM than it is at high RPM.that sounds very obvious what to listen for but i wonder if thats how it really sounds
I'm not keen on that unless it somehow sets an RPM dependant threshold itself somehow ? He's right of course, knock can happen anywhere, but the problem is that the engine's backround noise is often greater at high RPM than it is at low RPM. So if you configure the units threshold so that it detects knock at high RPM it might well go un-detected if it happens at lower RPM. The Knocklite works by having different thresholds at different RPM which in my experience is what makes all the difference. I was able to get them detecting faint knock at 3000rpm in turbo'd MX5's. With a fixed threshold that wouldn't have happened
I have emailed a few of the companies that used to stock the knocklite to see if they had any left and would like to arrange a group buy, still waiting for a reply.I'm not keen on that unless it somehow sets an RPM dependant threshold itself somehow ? He's right of course, knock can happen anywhere, but the problem is that the engine's backround noise is often greater at high RPM than it is at low RPM. So if you configure the units threshold so that it detects knock at high RPM it might well go un-detected if it happens at lower RPM. The Knocklite works by having different thresholds at different RPM which in my experience is what makes all the difference. I was able to get them detecting faint knock at 3000rpm in turbo'd MX5's. With a fixed threshold that wouldn't have happened
chris what about the knocktek for under £60 a few posts up? have you had any experiences with these?
No experience mate, sorry
I didn't think highly of any of them really until I had to set a couple up for MX5 guys, which changed my opinion of that type at least. I can't speak for other brands, suspect they won't be as good without RPM based thresholds.
the phormula knock that you stock does that have a rpm based threshold? is it a worthwile bit of kit?
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