InfernalVortex

iTrader: (4)

What do you guys make of this? I was reading something completely irrelevant to our cars, but it was interesting, and I heard some people make references to "det cans" ... Never heard of it, the words are too short/common for the TGO search to pick up, unfortunately...

http://www.lukekailburn.com/detcan.html





The idea is that you make a fitting and attach it to the block, and run a rubber hose to it, and then the other end of the hose goes to some ear protectors and you can, allegedly, hear spark detonation straight through the hose. These guys seem to use this specifically for turbo/supercharged cars where detonation is always a concern when upping the boost.

Now I have bad hearing, I've worn hearing aids most of my life, but I cant these days due to costs and being a broke college kid. That also means I cant afford to blow up any engine parts because I advanced my timing too far in the quest for speed.

What do you guys think of rigging up something like this...? Is it probably better to just rely on plug reading (which Im an admitted novice with)? I just have a hard time hearing something like spark knock over my exhaust system... and this is an interesting solution to that problem, although I presume law enforcement wouldn't appreciate the ingenuity of it. Not sure if there's any good place to put it on my car either. I'm guessing it would need to be attached to the block itself and Im not sure we have much on our blocks to attach it to that isnt already covered by accessory brackets, oil senders, engine mounts, etc. I suppose I could drain all the coolant out of the block and put it in the coolant plug hole just like a factory knock sensor, but I'd have to figure out a way to run that hose without my headers melting it.

fasteddi

iTrader: (2)

Wow, thats creativity forsure! And im sure its effective and a low cost way to hear KR over the motor.

Personally I look for spark knock on a laptop via tuning, as I cant hear KR over a roaring engine. I still check plugs for a sanity check, but Im doing everything possibe to make sure there isnt any KR. Just because you cant hear the knock when you getting on the throttle doesnt mean there isnt a little there, and over time that can really wear out your internals.

I am probly over doing it when it comes to spark knock and AFR readings..but thats just the way I was tought.

Beeman

Taht's pretty creative, don't see why it wouldn't work and what the heck it's cheap. You can also use a knock sensor from any computer controlled car. A Chevy knock sensor screws into the water jacket plug on the pass side of the block. The sensor itself is a piezeo crystal which generates voltage when it's vibrated. Same thing as your barbecue ignitior. Just screw the sensor in and hook a digital voltmeter to it and watch or record while driving.

88IROC350TPI

Seems kind of goofy considering, as the guy above stated, you can just install a knock sensor and get the same result.

fasteddi

iTrader: (2)

Reply to post #1

Hard to believe that someone would dump $$ into a boosted car. And is betting on reading accurate KR with some creation. Its definitly creative but I sure wouldnt bet my motor on that I can hear the KR in some headphones. I need a big laptop screen to tell me that im seeing knock while tuning. I see KR retard in degrees which is even better, IMO, any KR at high amounts of boost can ruin your day quickly, Exspecially if your ecm(if you have one) doesnt take out timing if it reads spark knock.

Checking plugs is just not enough I think, if you see speckled spark plugs then youve went too far.

InfernalVortex

iTrader: (4)

Well the places talking about it claimed their factory knock sensors got very unreliable with modified engines and I've seen similar things happen. I on the other hand only have a carb so no knock sensor at all. Not everyone runs a knock sensor.

fasteddi

iTrader: (2)

Good point, stock knock sensor are tuned to a specific Hz and once you mod a car it can deviate from that Hz.

If that set up works, then it works.