DIY_EFI Digest Wednesday, January 12 2000 Volume 05 : Number 018 In this issue: Re: Knock sensor. Re: DIY_EFI Digest V5 #17 Knock Sensor on Dyno Re: DIY_EFI Digest V5 #17:Knock sensor, etc. Re: DIY_EFI Digest V5 #17:Knock sensor, etc. injectors MC6803U4 info... See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Wed, 12 Jan 2000 08:39:22 -0500 From: Rodney_L_Wiggins@xxx.com Subject: Re: Knock sensor. It seems this discussion has illustrated two separate camps on the Knock sensor issue: the "simple microphone camp" and the "far more complicated camp". No offense intended for either group. For those in the "simple microphone" camp, MSD makes a universal knock sensor with an LED bar graph and alarm. Summit Racing sells it for about $150. It has adjustment for sensitivity and volume. It comes with a threaded "microphone" and an adapter to fit different size holes. I'm not sure of the manufacturer or availability of the microphone alone. (if someone knows, please tell me, I need to replace mine). It appears to be working on my application, but I'm sure its not as good as it could be, and I certainly wouldn't tune an engine by it. But when there was a problem it has warned me of it before I could actually hear the detonation. Perhaps everyone knows about this device but no one mentioned it due to a consensus that it is junk. If so, I apologize. Rod ------------------------------ Date: Wed, 12 Jan 2000 08:59:06 -0500 From: "jtyler" Subject: Re: DIY_EFI Digest V5 #17 Thanks. OOOH My wife has a Tahoe, where is that ECM? Yet another way to piss her off! My GM literature is on the way! That should answer some of the more basic questions and prompt alot more. Jim From: "Bruce Plecan" Subject: Re: GMECM and Crank Sensors First one that jumps to mind is the late vortec. You really need to find a parts house that has some catalogs with photos for part ID'ing. They do exist from Delco, and Standard Electronics. Grumpy ------------------------------ Date: Tue, 11 Jan 2000 19:23:15 +0000 From: Ade + Lamb Chop Subject: Knock Sensor on Dyno At 05:00 11/01/00 -0500, you wrote: >> >> Knock Sensor on Dyno >> >> See the end of the digest for information on subscribing to the >> DIY_EFI or DIY_EFI-Digest mailing lists. >> >> I am currently building a eddy current dynamometer for testing small engines >> up to 70 ft lbs of torque. I am working on the instrumentation now and I was >> reading the archive and started thinking about knock sensing. > >> like to use a sensor out of the junkyard to keep costs down so any ideas of >> which one would suit me the best (partial to GM parts)? > >The one problem that comes to mind if you were using the GM knock sensors >is the sonic qualities of knocking in your small engine. From what I've >read, the knock sensor is tuned to specifically hear+amplify the >characteristic knock sound for that bore diameter, and block. GM has had >several different knock sensors, and even had a different one for the LT1 >and LT4, even though they have the same dimensions (LT4 was supposedly a >little noisier). If you have the same bore, then I guess the knock would >sound similar. If it was me I would just plant a microphone somewhere on the block then use software to sort out what is and what isn't just like humans do.... Much easier to do than tuning sensors... the amount you pay for Hi-fi Microphones/speakers is testament to this. Ade ------------------------------ Date: Wed, 12 Jan 2000 07:24:39 -0800 (PST) From: Carter Shore Subject: Re: DIY_EFI Digest V5 #17:Knock sensor, etc. Thanks Bruce, I had not thought about noise contribution from mech valvetrain. And of course, IGOR will allow some very accurate knock detection, but I didn't think it was available yet. Here's a Q, do you know how/if GM systems handle false KS trigger, vs RPM? For example, say an ECU has a KS sensitive to say, 4,000 Hz. Frequency of bormal internal noise from the motor varies with RPM, so at some RPM, it will also create 4,000 Hz noise that would trigger the KS. Does the code ignore KS at certain RPM? Bill, I looked at your site, it's good stuff. I had seen the app note, was looking for a simpler (lazy and cheap) way to do it. Plus, if my motor's knock signature matched a stock unit, I could just use off the shelf stuff. I downloaded your knocking WAV file, to play with. I did not see a display where you had examined the signal in 'line' or 'bar' mode. This would show up any resonant freq and harmonics as spikes, much easier to pick out specific components of a sound. Requires a sound card in PC, so I'll have to wait 'till I get home to try it. Does anyone have access to a supply of different KS? It might be useful to document the resonant freq and output levels of various stock parts. Just need a signal generator and a scope (or Spectrograph). I'll volunteer to run the tests, if we can work out a way to ship the units. Some details to hash out if any interest. Thanks all, Carter __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com ------------------------------ Date: Wed, 12 Jan 2000 07:24:39 -0800 (PST) From: Carter Shore Subject: Re: DIY_EFI Digest V5 #17:Knock sensor, etc. Thanks Bruce, I had not thought about noise contribution from mech valvetrain. And of course, IGOR will allow some very accurate knock detection, but I didn't think it was available yet. Here's a Q, do you know how/if GM systems handle false KS trigger, vs RPM? For example, say an ECU has a KS sensitive to say, 4,000 Hz. Frequency of bormal internal noise from the motor varies with RPM, so at some RPM, it will also create 4,000 Hz noise that would trigger the KS. Does the code ignore KS at certain RPM? Bill, I looked at your site, it's good stuff. I had seen the app note, was looking for a simpler (lazy and cheap) way to do it. Plus, if my motor's knock signature matched a stock unit, I could just use off the shelf stuff. I downloaded your knocking WAV file, to play with. I did not see a display where you had examined the signal in 'line' or 'bar' mode. This would show up any resonant freq and harmonics as spikes, much easier to pick out specific components of a sound. Requires a sound card in PC, so I'll have to wait 'till I get home to try it. Does anyone have access to a supply of different KS? It might be useful to document the resonant freq and output levels of various stock parts. Just need a signal generator and a scope (or Spectrograph). I'll volunteer to run the tests, if we can work out a way to ship the units. Some details to hash out if any interest. Thanks all, Carter __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com ------------------------------ Date: Wed, 12 Jan 2000 12:03:44 -0700 From: cwagner@xxx.net Subject: injectors I have a couple of injectors that I need flow rates for. I have looked around and have found nothing. Maybe the people on the list could help. Here are the numbers: Bosch 0 280 150 209 Bosch 0 280 150 902 Siemens 4418474 With this, what is the formula to get sec/gram from #/hr or grams/sec. I haven't messed with this stuff that much. ------------------------------ Date: Wed, 12 Jan 100 20:11:41 +0100 (MET) From: "Daniel R. Henriksson" Subject: MC6803U4 info... Hi I'm in the process of reverse-engineering a Weber/Marelli ECU (IAW048/01) and i need to clarify some things about the CPU. Does anyone know the difference between the 6803C and the 6803U4? After digging on the net i have found out that the 6803U4 has an additional 64 bytes of onboard RAM at 0x40-0x7f. But i suspect there is some other differences, what about timer capabilities, there is a new SFR at 0x18 that's supposedly a timer control register, anyone know the specs. for that register? If anyone has any additional information then please inform me! Some of my findings can be viewed at: http://www.ludd.luth.se/~rotax/ BR Daniel Henriksson rotax@xxx.se ------------------------------ End of DIY_EFI Digest V5 #18 **************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".