LET'S TALK TECH-NEW KNOCK DETECTION DEVICE (TEST?)

[@FWLR.tuning]

I MIGHT be biased, but I think you should definitely test it!

[@richardholdener1727]

points

[@hondatech5000]

Unit cost?

[@justme2661]

Yes do test It, I would like to actually see a knock sensor that was tested and hopefully could be tested

[@jsmcortina]

For "correct" knock sensing you need to be synchronised to engine position. A standalone sensor is going to struggle to distinguish other noise if it isn't listening at the right time. If your ECU can't provide that angle windowing, I think you'll have trouble being accurate. I've tested on a chassis dyno, introduced knock and detected it.

[@FWLR.tuning]

Yes this is for audio knock detection, as opposed to knock control strategies. Nothing can beat your ear/brain when it comes to distinguishing knock from other engine noise.

[@bobroberts2371]

@@FWLR.tuning But how would one decide what is knock Vs some other engine noise ( like normal high load ) if they never heard either before?

[@FWLR.tuning]

@@bobroberts2371 I will be providing a library of recordings along with instructional videos to demonstrate

[@bcbloc02]

Hey we know long runner headers are a win besides they tend to be not long lasting and they tend to burn sprak plug boots. Some great cast iron long tube headers would be awesome! Nick at Nicks Garage has had some of those big crazy mopar castings that were kind of like headers make very close to the same power as headers. It seems like low hanging fruit the factory has tended to skip.

[@jamesgeorge4874]

Most of my experience is OEM controllers, and HPTuners, so knock sensors have always been part of tuning, this should be interesting. One thing that is really cool about GDI / GTDI fuel systems is the ability to use 87 octane, (relatively) high compression AND boost. The new LU3? 2.7 4 cyl turbo in the Silverado/ Canyon/Camaro can make 430 LB/FT of torque, from 1500-4000 RPM, on pump 87.

[@hondatech5000]

FWLR tuning. I went and checked the dudes site out and actually read the user manual. Would be very cool if it works and it would be great to have a test and discussion video just to talk about how the sensor works how it “hears” knock what to look out for factory vrs something that you adjust the sensitivity on (like this). Something with a wild cam or a pdb that makes noise that would normally confuse a factory sensor.

[@randy6350]

Richard, Dead serious I’m pulling out my supercharged engine, water / meth & Heltech tune and going with a 06 aluminum 5.3 L33 w/ only a Summit truck cam just so I can keep the maintenance up and run on 87! Sick and tired of buying junk 91 and octane additive! So I want NA reg. pump gas!

[@bcbloc02]

I have replaced a lot of nissan knock sensors.

[@ChurchAutoTest]

Best way is still with in cylinder pressure sensors. The spark plugs with pressure sensors built in exist, but they are expensive and I don't think they'd last long enough even if prices came down. You can use both peak pressure generation as well as looking at waveform fluctuations to detect knock. Of course, the problem is still that you have to have knock before you can mitigate it. Any materials guys out there want to comment on how the pressure sensors could be made more durable/less expensive? I think they need to be able to read up to 5000 psi

[@richardholdener1727]

expensive and short lived...not the ideal combo but the data would be awesome

[@bennvennelectronics]

@@richardholdener1727 Saab's used ion detection built into the ignition coil to monitor cylinder pressure using stock spark plugs. It's probably the *only* accurate and reliable way to detect detonation without extensive tuning of the knock filters. Harley-Davidson also used ion detection instead of a cam angle sensor to know when #1 is on its compression stroke. They removed it after a couple of years so maybe that wasn't too reliable. Maybe I should design a replacement LS coil or similar with a knock digital output?

[@studio571]

Best way to get right freq is to calculate it and filter all other freq range with hi & lo pass filters

[@ab.motorsports]

Definitely need to test!!

[@bobroberts2371]

Early 80's GM used a knock interface signal processor ( A 4 " x 4 " x 1/2" black box mounted on the firewall / engine. ) this might be worth exploring as a junk yard solution though I don't expect it to be very sophisticated. From what I recall, knock sensors are made with different frequency ranges so this will need some experimentation. Does the knock interface in the vid have a tach / cyl 1 input? Having this info would be vital in filtering out time in the combustion cycle when it is impossible for knock to occur. This would have more value on a 4 cyl vs an 8 where combustion cycles are starting to overlap. Another possibility is to run the engine on an aftermarket ECU , retain the factory unit for knock sensing since it is designed for that motor. Feed a constant RPM / throttle / MAF reference so the factory ECU thinks the motor is at steady state. Monitor the spark advance parameter over OBD 2 then alter spark advance in the aftermarket ECU. If the factory ECU supports " knock detected " that would be helpful as well.

[@champspec]

There’s another device called a knock link… its been out for awhile and it looks like a shift light. But its supposed to be self adjusting.

[@nickl3872]

Thank you i missed then live stream

[@bonzainews]

looks like its time to get a patreon so you can have extra cash to buy more things to test...

[@douglash3129]

I had a warranty job with a rattle in the right rear, empty coke bottle Factory Installed!!

[@Blackinterceptor999]

My new 4.6 I believe has 2 knock sensors instead of the single sensor my old engine has....is there perhaps some way to use both sensors with my stock harness? most people just delete the other sensor but I'd like to investigate the possibility's of using both if I can..

[@richardholdener1727]

NOT SURE ON THAT

[@justme2661]

Trusted

[@manitoublack]

any good aftermarket ecu should have gated knock detection.

[@johnj2496]

🤔 a knock sensor it just a microphone i wire a 2 wire one to a mono head phone jack and yes you can hear all the things i wonder if a music sound enginer has a frequency filter to clip out x x x sounds and only allow the knock frequencys to stay you might be able to do this running it thru a good equalizer on your car sterio and jam out as you drive to your engine tunes

[@BLKMGK4]

Wishing for Ion sensing!

[@ab.motorsports]

I'd like to know on a built motor with forged pistons how good it works then.

[@FWLR.tuning]

I use one on my built GTiR motor with solid lifters and forged pistons. The engine sounds like shit through the headphones but the knock is unmistakable haha

[@ab.motorsports]

@@FWLR.tuning ok second question. If knock is a certain frequency I guess the sensing boundaries go from low to high? But it's always same frequency? It's just how much?

[@ab.motorsports]

@@FWLR.tuning And have you come up with a scale of how much is low knock to high knock I'm guessing leds is like 1-10?

[@adrianlastname4864]

I still prefer saab knock detection through the spark plug

[@FWLR.tuning]

I believe my N54 does some similar wizardry in addition to the normal piezo knock sensors attached. This product is mostly meant for audio knock detection so you can use your ears/brain to determine if knock is occurring.

[@bobroberts2371]

The SAAB Trionic system is interesting however I wonder if it will be effective at high RPM due to the need to resaturate the ignition coil for the next spark event.

[@ChurchAutoTest]

@@bobroberts2371 I believe Trionic actually predicts/detects knock by looking at ionization potential. So there shouldn't be any issue as long as you can still have enough coil energy to spark. The predictive aspect is nice, but I don't know how well it applies across different fuel types.

[@hondatech5000]

I just read my plugs but I would take some flashy lights to warn me if something goes wrong…

[@FWLR.tuning]

@@hondatech5000 yeah I always check my work by doing a clean pull on a fresh set of plugs and examining them. The real value I find with my device is that you get instantaneous feedback through your headphones or car stereo.

[@1magnit]

Seems like everyone has an opinion yet they don't understand the basics.

[@1magnit]

The commonly held belief about detecting knock was based on a university thesis full of mistakes and never peer reviewed. Knock frequency is based on bore size. Lies.

[@FWLR.tuning]

@@1magnit Working as a music producer full-time for the past decade has given me a decent amount of experience staring at waveforms. What I have found after digging through tons of my own knock recordings is that although the size of the bore contributes to the resonance after a knock event, it's really the initial impulse that is easy to separate from the rest of the engine sound. I think there is some truth behind tuning for a specific bore size because there will be a strong resonance determined by that, but if you ever look at a recording of a knock sensor it's really hard to miss the sharp spikes.

[@1magnit]

@@FWLR.tuning If you're sampling at 44 KHz you can't detect anything higher than 22 KHz. Every 3 dimensional cavity has 3 resonance frequencies. In the case of a cylinder it has 2. The bore is the least important because at 15 deg ATDC there's only about 1 mm of it

[@FWLR.tuning]

@@1magnit yep. But just listening to the signal negates all of that haha

[@1magnit]

@@FWLR.tuning Ears don't work, that's why we use instruments.