RT

Interesting observation - I had always thought that the KL was more sensitive than the OEM knock sensor. The KL's sensor is mounted on the block and set to max sensitivity. Over the last 2yrs, it has not given me anything more than 1 steady green at 4000rpms (as the boost hits max) and another steady green at 7000rpms (presumably engine noise).

Here's the interesting bit. My advance multiplier was 16 last week. The ign correct table (8X8 table) was showing 0.0's at all points, except at one point which was showing -1.8.

After a good blast yesterday afternoon (ambient temp about 32degC), I checked the AM again and it had dropped to 13 (!) with the ign correct table showing a lot more values. Most were positive, but there was one point which was -0.4. All the while, my KL was not giving me more than 1 steady green at all RPMs.

This seems to suggest that the OEM sensor is hearing and doing things, that the KL is not.
Comments?

dowser

Is sensitivity on the KL set to max, and have you used det cans to verify what the KL is displaying?

Richard

RT

Yes it is max. No not used det cans. But even if I did, there's nothing more that can be done to further increase its sensitivity.

Dark Blue Mark

Have you tested the KL, with the spanner tap test?

MB

Andy.F

You can pick up det with the cans that the knocklink will not display, that is what the OE ECU will be reacting to. It is also possible, depending on the car, to show 2 greens at higher rpm and have zero knock.
You really need to check your particular set up with det cans in order to be able to interpret the knocklink signals correctly.

Andy

Thunderlips

I had a similar problem, knocklink showing only one green, but when I had my link ecu wired up to my laptop the standard knocksensor was telling me that I had an engine blowing amount of det, the ignition was backing off to a ridiculous level to compensate etc etc. I confirmed that there was nothing wrong with the knocklink by borrowing an unfitted one and wiring it up temporarily, only one green on that as well, and I had octane booster in. So it looked like the stock sensor was gubbed. I replaced the stock sensor at great expense, and all was well again. Talking with others it would seem that this failure is not uncommon! Hope you get it sorted:-)

Razor2001

Hi,

One thing of note is that maybe its the position of where the stock sensor is mounted vs. the after market sesnor. I had way more activity on my KL when I had my after market sensor stack mounted on top of OEM sensor as compared to where it is mounted now where everyone elses after market sensor is located.....just some info

Can one make a pair of det cans or do they have to be purchased ? Can an ametuer hear det via det cans or would you need a pro ?


Cheers,
Ray

krazy

Think you can make them...
Copper tube, flatten one end, add length of thick walled hose, and a set of ear defenders.
Some more info in this thread
http://www.sxoc.com/vbb/showthread.p...6&page=2&pp=20

Razor2001

thanks crazy gonna look into this.....cheers

RT

Thanks guys, I know the KL can "miss" det as I've heard det with only 2 greens showing.
I'm just a little surprised to find that the car is that much more sensitive than the KL. Looks like the Subaru boffins really run their car at the limit.

dowser

I've seen quite a few KL's where the sensitivity pot is dry-jointed, rendering the thing useless (normally though, this means no single green power lead).

As Andy mentions, it important to cross check what you're seeing from any knock sensor (factory, or aftermarket) with a set of det cans. The home made stuff is fine (I don't know anywhere that sells them!), and you'll hear bad det no problem. The tinkly stuff is a little more difficult.

RT - maybe just a bad tank of gas?

Richard

Andy.F

What do you think of the 'tinkly stuff' Richard ? I map it out on customers cars but on my own, I found the best performance with a light tinkle yet the engine is still running sweet 2 years on.

Andy

RT

For discussion's sake, anyone know how ign timing is run on the EVOs? They seem to make *similar* power and torque - do they use a form of active ign timing as well?

I know a mate who went from a JDM STI to an Evo8- He commented that the EVOs don't show as many greens as frequently. The KL's usually silent, and once or twice on the track it flashed the big red. Thoughts?

Razor2001

Yea I am not sure about the quality checks on the Knock Links but my top light definately arrived none functional. I am going to open it up this morning and see whats busted / not soldered.

I was reading something about how minimum det may not lead to engine failure and that it may not even be that harmful...or something along those lines.....

Here it is, awesome read imho about det and pre-ignition

http://www.clubwrx.net/forums/showth...threadid=14426


Cheers,
Ray

dowser

Same Andy. I'm running without on mine currently while I play with boost, but it's definitely less of an edge. Problem with tinkly on road, means big red as shift light after 20 mins on track (with my TMIC...ho-hum)....but that's why god invented methanol

Customers are without, but I have one mildly tinkly STi7 that has been going very strong for 18 months now. Owner wants it to go bang as an excuse to upgrade, and drives it with this intention....which is probably why it hasn't

RT - I find every car to be slightly different, even within the same marque and model. A single orange can be det on some cars, but background noise on others. You really need to cross reference the KL display to reality with det cans.

Richard

PS: Andy - tell me what to do about head studs; OE or ARP?