FWLR Tuning Knock Detective
 

Just came across this standalone knock detection device. I'm curious to see what other people's impressions are. I'm not affiliated with the product in any way.

Standalone, 52mm gauge form factor, headphone jack and warning light. Adjustable sensitivity via a set screw. Looks like it would be about $200 USD shipped.

Some people were critiquing the lack of tuning for specific cylinder bore sizes or frequencies. I'm far from a tuning pro, so I'm not sure how big of a deal that would be.
I haven't come across much else in this price range. Curious to hear others thoughts.

Side note, I know that Speeduino was working on a standalone knock detection system a while back, but I believe that project has been stalled for a few years.

Store page link : https://www.fwlrtuning.com/product-page/knock-detective
Youtube Demo :

I literally just installed my knock detective today! Great kit. Pulled my stock knock sensor on my VVT and ran a helicoil in to thread the sensor bolt. Read a bunch of forums and decided an 8x1.25 helicoil was definitely the cleanest and simplest route. Added 2 degrees of timing across the map with confidence!

Your post on Facebook was the first I'd heard of it. I thought maybe someone on here would have thoughts.

Glad its working well for you.

Did you have any trouble setting the sensitivity up? Audio quality is good?

No issues setting it up at all. Just followed the instructions in Nick Fowler’s YouTube video to a T. I still need to run the analog output to my ECU for logging, but I was able to enduce knock at 3000 rpm to dial in the settings. Took about 50 degrees 😬. Had me sweating bullets lol

We're going to have very similar setups soon I think. I'll be getting 640's soon and dropping my new engine in.

Are you running AC? I am, so I think I only have one more input available on the Speedy. Even if I do get the Knock Detective I'll likely leave it disconnected from the ECU so I can add oil pressure.
I really wish these boards supported 4+ aux inputs.

yea I’m running A/C, went ahead with the 202305 updated firmware. Makes A/C control MUCH more robust with closed loop idle. I can confirm 202310 firmware was super buggy on my SpeedyEFI.

I do wish for more inputs on this ECU. More than likely I’ll leave my Knock detection as audio/visual only. The logging seemed kind of noisy to me based on that video. The audio feedback for me was very clear when knock occurred. Even if the sensitivity is off, you’ll know without the LED’s when you hear the knock

Hey guys, I'm Nick (FWLR) - thanks for checking out my product! Just wanted to hop on here in case you had any specific questions that I can help with.

Regarding the bolt hole size, I have drilled the sensors out to an M10 many times without issues. You just gotta use a drill press, lots of lube, and go slow so you don't melt the plastic around the Bosch sensor.

Lemme know if I can help in any other way :)

Love your product! Gave me the confidence to start pushing that timing table to maximize power and efficiency with just road tuning. I wanted to use the bolt you supplied and happened to have an M8x1.25 helicoil sitting around. Good to know it’s safe to drill a bit!

Crazy that you got 50 degrees into it at 3k. I'd be sweating bullets too. Once you get that turbo on there you're gonna find the knock threshold a lot easier haha

also DAMN I miss forums

Hey @FWLRtuning, would you be able to provide the thickness of the supplied knock sensors? I was thinking about mounting options and figured a stepped stud (m8 on one side, m10 on the other) would be my preferred mounting method if I can find one that would work. I just wanted to make sure the m8 side would be long enough to get through the sensor.

From the top of the sensor to the bottom is 18mm. The diameter of the circular part of the sensor is 26mm.

Ok, cool. I found those measurements online but wanted to confirm that your sensors had the same sizes.

Unfortunately, I realized that all of the step studs I had found are m10-1.5 instead of the m10-1.25, which is what the blocks threads are. I suppose drilling or a helicoil will end up being the answer.

I can't emphasize enough how easy the helicoil method was! Just spin in the m8-1.25, cut the provided bolt to length, and snug it down. I was able to do all of that without removing the intake manifold. It was an awkward position, but with the front passenger wheel off, it's doable for sure.

Cool product Nick - great form and function. Straight to the point.

How sophisticated is the filtering on this? It seems pretty good from you're Youtube demonstration videos. I have a Phormula setup currently for external audio knock detection.

On the 0 to 5v analogue output - does the sensitivity gain on the dial also increase the signal size on the output channel or is it only the signal thresholds for the dial's warning lights?

So in this version the Knock Detective is not overly complicated. It's all analog and it has a filter that cuts off below around 6kHz. The output is just the amplitude of that filtered signal, and the LEDs represent that. So changing the sensitivity will change both the 0-5V output along with the LED range.

It does require some interpretation of the user, but its very easy to tell when output is smoothly growing with RPM vs sharp spikes which would indicate knock. I am currently developing a microprocessor-based next gen version that will take the interpretation out of the hands of the user. I'm pretty excited with the algorithm I've developed is at, but it still needs more testing and validation before I feel comfortable releasing it.

The user manual goes into more detail here - http://FWLRtuning.com/manuals

Thank you Nick.

All of that makes total sense and proves it does not need to be over complicated. I like the simple approach to your current product and its what I expected as the normal noise level of an engine increases with RPM and can oddly increase slightly with boost/power so it is hard to keep that level constantly normalised for automated knock detection. Good ECUs do this with careful setup but its much more complex to setup for the user and could lead to more errors and miss detection from poor setup.

A straight 6k bandpass filter also explains how it can be used on different engines and not only effective on certain bore sizes/natural frequencies. I've found on my Haltech that the second order bore knock frequency is a stronger signal than the first order. The ECU detection works really well but I like to have audio knock detection when tuning as back up and required it for the initial setup to verify my settings.

The analogue signal output from your gauge actually looks more intuitive to read compared to the square sampled output on the Haltech logs. Hence it looks good as a further input into my logging - a further back up.

I'm in the UK - we push high boost on pump gas - we squeeze timing - its a necessity.

Many thanks

Happy to help!

Here's a video going into a bit more detail for those interested.

This is really slick. @redursidae this looks like a sweet street tuning tool.

Finally got around to the better version of that video I promised :P

Again - ace and to the point.

Potential query if not covered - what logging frequency do you require/recommend to avoid missing knock events on logged data? Many Ecus let you dilute the logging frequency to save data memory but could be a gotcha if set too low.