Let me start by saying I have a leaking headgasket. Honestly I don't know what caused it, but I have many theories like...

- the block defect that the head stud hole isn't drilled deep enough
- machine shop only torqued to factory specs during engine rebuild
- and then there's the big D word......detonation.

Detonation is one of the leading causes of our car issues. It personally cost me around $2500 and 6 weeks of downtime when I cracked all my piston lands. If we could monitor engine knock this would become so much less common.

The 4g63 guys have it easy. Pop in a EPROM ECU and DSMlink and your tuning capabilities are endless. We're trying to retard timing at higher boost levels to what we assume is a safe level to prevent detonation. My roomie has a 95 GSX w/DSMlink and he's actually advancing his timing because he can tell when his car begins to knock. And let me just say, his car pulls HARD!! It's just so much easier for him to tune.

So there must be a way for us to monitor knock. Is anyone doing it now? I see lots of products on the internet ranging from $69 to $600+ for monitoring engine knock. Has anyone tried them? I remember a discussion on the J&S Safeguard a while back, and I think it was determined that it wouldn't work with our ignitions or something. But the J&S is designed to retard timing per cylinder for knock. I just want to be able to SEE that I'm knocking. Some people say you can audibly hear engine knock, but I didn't hear anything when my engine blew.

So let's hear some input from other members? What have you guys tried? What works and what doesn't? Are you content on tuning with A/F and EGTs?

You are not your job.
You're not how much money you have in the bank.
You're not the car you drive.
You're not the contents of your wallet.
You're not your fu**ing post count.

97 Eclipse GS - *SOLD*
01 Audi A6 2.7T
01 YZF-R6

ok i understand where you're coming from, being worried about knock and all but you're missing the point i think.

just keep your eyes on the a/f and you'll be fine. keep the boost nice and cool and always out in good gas. tuning to the a/f works, especially with a datalogger handy to show much advance is actually being pulled

knock is just the by-product of a crappy tune

_ _ _ _ _ _ _ _ _

96 Black ESi
91 Red TSI AWD (RIP)
02 WRX


"turnin wrenches for nine hours in the pouring rain, just to get the beast up and running again"

Aerospace Certified TIG welder for Precision Castparts in Portland, OR.

JoshSpair.com

You are not your job.
You're not how much money you have in the bank.
You're not the car you drive.
You're not the contents of your wallet.
You're not your fu**ing post count.

97 Eclipse GS - *SOLD*
01 Audi A6 2.7T
01 YZF-R6

Well obviously you need the textbook EGT and A/F guages, but maybe you should invest in a higher quality wideband 02 sensor set up considering a decent EGT and a wideband O2 can allow you to practically tune the car without a dyno (unless you want horsepower numbers). They're becomming more and more affordable as people realize that blinky lights are for ricers. I also think you're high altitude there in CO. I can't remember if the thinner air is a bonus or a detriment to your tuning. Less oxygen by volume, so I'm thinking you're a bit safer?

I know that xtremeRS or someone had come up with that sound amplifier to listen to his engine internally for knock and I spoke with him briefly that it could be possible to wire such an amp up to the AUX inputs of your stereo so you could listen to your engine through the speakers at any time. It's possible, but we don't know if it would be ideal or not.

Just some thoughts...

Best solution for me....

Wideband 02 sensor... and tec3 computer.
omg makes a world of difference, and the best 3.5K I've spent.

http://www.gmcmhphotos.com/gallery/showalbum.php?uuid=mrerf&aid=59
there is the schematic for making a knock detector using basic parts.

1998 dodge avenger 4 cyl AT
Mods are:
Not enough

i have the safc 2-- it monitors engine knock- dont know how accurate it is cause i have no basis for comparison-- and like you i dont hear when my engine is knocking and i have a good ear. i got it for 315 or so online. its got a nice display- i was able to tune my car to run 50lbs injectors- not perfect yet but at least it runs good
(also have an aem fpr)

Also, just dont assume if you run really rich, you wont get knock. Take me for example, i run 11.0:1 A/F ratio, and if my boost spikes to 17 psi, it will knock. 15 psi is just fine though..You have to remember, its not just a lean A/F ratio that can cause knock. Factors such as ignition timing advance, fuel octane, boost pressure, air intake temp, coolant temps, and even how good or bad the exhaust is able to breathe. A restrictive exhaust can contaminate an A/F charge and heat it up enough to cause knock..I'm pretty sure thats what my issue is at the moment..Stock cams- my exhaust is not breathing good enough, er not getting out the exhaust fast enough..at least for 17 psi. I also have a bit high EGT's around 1580 on a long pull. You can't feel knock, but you can hear it, at least when its bad enough. Some slight knock you can't hear too well, but its def audible from in side the car, if your windows are up, stereo off, ect..sounds like its coming from the glove box area, and its a metalic rattle sound. The listening device i made works, actually works too well, as it amplifies the entire motor, making it hard to hear it. I used 2 mics though, which is prob why..

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)

I feel what boostgs is saying. Won't it be great if we have some type of stand alone with 2g-turbo-type abilities of pulling timing automatically? Awww, one can dream I guess

edit: ok maybe I am insane, but... we have a know sensor right? Is there anyway we can mod it to make it more effective?


-------jezreel
1998 GS with hrc stage 2, sfmu, ml, prokits, egt, boost gauge, apexi tt, haydans tranny cooler, costum dp, dr. uber groundwires, dynotune fp gauge. gst muff, turbo spoiler
Boostin since Aug 03.

nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!!
thanks for www.kaptainmyke.com for the sig hosting

Originally posted by jsupetran
I feel what boostgs is saying. Won't it be great if we have some type of stand alone with 2g-turbo-type abilities of pulling timing automatically? Awww, one can dream I guess edit: ok maybe I am insane, but... we have a know sensor right? Is there anyway we can mod it to make it more effective? -------jezreel 1998 GS with hrc stage 2, sfmu, ml, prokits, egt, boost gauge, apexi tt, haydans tranny cooler, costum dp, dr. uber groundwires, dynotune fp gauge. gst muff, turbo spoiler Boostin since Aug 03. nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!! thanks for www.kaptainmyke.com for the sig hosting

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Megasquirt powered 420A
Custom turbo system

http://www.ms-custom.com

well speaking from experience and having to try and work around cali's cat piss 91 octane and still run high boost i just invested in a water injection kit, it showed noticeable drops in intake air temps (datalogged) as well as increased timing at WOT, also kills a lot of the knock factor by cooling the intake enough to avoid it. its actually seriously a good investment...i'd look into it (xtremers too, sounds like you're right about the restrictive cams)

_ _ _ _ _ _ _ _ _

96 Black ESi
91 Red TSI AWD (RIP)
02 WRX


"turnin wrenches for nine hours in the pouring rain, just to get the beast up and running again"

Aerospace Certified TIG welder for Precision Castparts in Portland, OR.

JoshSpair.com

The problem is that knock has a different frequency and amplitude for every engine. Someone would have to test and experiment with different equipment and discover the knock point of our engine. I'm not prepared to use my engine as a ginnea pig. I just hope that some company like J&S can get something going for us.

yea knock sensors are tuned to the bore size i think

edit:

http://www.ni.com/pdf/svix/us/engine_knock_datasheet.pdf

_ _ _ _ _ _ _ _ _

96 Black ESi
91 Red TSI AWD (RIP)
02 WRX


"turnin wrenches for nine hours in the pouring rain, just to get the beast up and running again"

Aerospace Certified TIG welder for Precision Castparts in Portland, OR.

JoshSpair.com

Here is a good read about detonation...

http://www.streetrodstuff.com/Articles/Engine/Detonation/

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)

from that article, the resonant frequency of detonation is 6400 hertz, period. it'll variate somewhat around that area, but that is the frequency your sensor needs to be sensitive to.

DarkOne> Well if it's isn't EZ_Daring, the oldest newbie ever!

Well depending on what part of CO you live in, I could give some help with tuning, I used a wide band O2 S-AFC MSD DIS-2 and some fuel mods and for about 8 to 9 months now I have ran 25psi on 91 Octane without any problems with a 11.3:1 A/F, well except tranny but you know. So if you want some help and live anywhere around Denver Email me at Therein10@msn.com, I don't check this board very often so that would be the best bet.

I purchased an MSD knock sensor. It comes with the sensor of course, and a display that tells you if you are getting knock. The display is in green, yellow, red. Once you hit red, you have knock and it tells you. I haven;t tested it yet as my car is down, but I will comment once I get my HRC portfueler. PLus I have an FJO wideband, it should help.

:shrug ... where the hell did you find an MSD knock sensor?
sounds kinda cool and the display seems helpful ...
how much did that run ya and where did you buy from?

-MIKE-

Stroked 2.2L