Re: Programmable knock control systems
 

John,do you make that happen with a laptop or some other method?

Re: Programmable knock control systems
 

The unit is programmed with a Motorola development system, so it must be sent back for software changes.

There are no ROM chips. There is no user software. The parameters not controlled by external knobs and switches are embedded in the code, which is proprietary. To protect the design, the processor in use erases its flash memory if attempted to be read from the outside world.

Re: Programmable knock control systems
 

Looking forward to it.

Re: Programmable knock control systems
 

John, any feedback on the dyno tests?

Re: Programmable knock control systems
 

The promised report is:Two separate systems were compared.The J&S Safeguard / MSD 6M combination .......The other was the Crane HI 6/Anson combination.The J&S appears to have a faster response time,has more visual reporting through the LED lights,more fine tuning capability and the plus feature of individual cylinder recognition.....No horsepower gains or losses were noted by either system......The included system check used with both systems, was tapping on the sensor with a wrench.....Therefore,in my opinion,while detonation is the topic and obvious use of these systems,the unspoken benefit of component " failing " recognition may be even more valuable.....Be it, a part of valve train,timing chain,piston slap and etc.,when metal to metal occurs , the alarm goes off and timing comes out......The system design parameters may be capable of engine shut down, if so desired.....Regardless,I feel this type of system is " must have protection ". Further,the system may provide some of the same benefits on fuel injected motors.

Re: Programmable knock control systems
 

Sounds like you found a winner. Thanks for the info.

Re: Programmable knock control systems
 

CcanDo. who does your engines, Just curios because my engine builder was also going to test these system today.

Re: Programmable knock control systems
 

42MTI,Who is your engine builder?

Re: Programmable knock control systems
 

Louis Boyd, who do you use?

Re: Programmable knock control systems
 

Hi MTI 42, You already have piston sprayers from my fixtures.....These are new motors we have tweaked the design on.....Completely disassembled,changed several components and reassembled.....Bits and pieces of design from Dubui race team,Keith Eickert,Sterling,Zul,ourselves,Boyd Machine and others.....Boyds have done the additional machine work and reassembly.The application focus is on pleasure/poker run that is user friendly,durability and competitive power,in that order....Sanitary aesthetics is a buy product......We have more thoughts to come while looking at the marine industry as a possible business endeavor.........We will be doing a similar process to the next new set of motors,shortly.

Re: Programmable knock control systems
 

CcanDo,

How would the J&S Safeguard capabilities/features relative to knock control with the GM ECU compare with the Merc PCM555 which alledgedy also addresses knock events on a cylinder by cylinder basis for fuel injected engines?

Re: Programmable knock control systems
 

John_at_J&S,

Do you have a web site? If so what is the URL.

What is the price of you marine unit and where is it available from?

Can you identify which frequency range is used for the Mercruiser 496HO part number 878187 knock sensor?

Re: Programmable knock control systems
 

I used Crane/Anson system on 36 Skater with 1150 Sterlings. No problems what so ever. You need to run the tach test. I found tach signal off above 6000. Both of mine read 7400 for the 7000rpm test. Rev-limiter has to be set accordingly. e.g. (7000rpm rev-limit on Crane box give me a 6600rpm rev-limit)

Re: Programmable knock control systems
 

Rage: We are not a supporting vendor. I don't know how the product fits in with LB's lineup, but they may carry them after further testing.

GM sensors have the part number engraved on the body, such as "10456082". This number crosses to AC Delco "213-95", but the sensor is still marked with the GM number.

Mercruiser may have the sensor marked with a custom part number.

Re: Programmable knock control systems
 

Just wondering how you know about my motors and If there is anymore I should know. Also are you developing a marine line up. I'm a little confused. :D

Re: Programmable knock control systems
 

John, will your Safeguard unit be on display at any of the boat shows?

Re: Programmable knock control systems
 

John,

What is the GM part number for the 5.2kHz knock sensor that will fit on the 496HO? I want to check and see if that is the unit on my 496HO.

Thanks.

Re: Programmable knock control systems
 

GM makes several sensors tuned at that frequency. Mounting thread and internal load resistance account for the many part numbers.

Key on, engine not running, knock sensor connected, measure the DC volts on the knock sensor wire. If it reads about 2.5v, then the sensor load resistance may be important.

With the sensor disconnected, measure the resistance of the sensor itself, between the pin and the body (ground).

Report thread size and load resistance.

Re: Programmable knock control systems
 

John,

The sensor (pn 878187) is a donut shaped unit with an electrical cable and pin connector. There is no thread. The sensor is bolted to the block with a stud (PN 16-862915) with a "0.25-18/M10 special thread". Is this the thread to which you refer?

The sensor is at the lake. I will measure the sensor resistance next trip.

Re: Programmable knock control systems
 

That sensor is "non resonant", meaning that it's not tuned to a particular frequency. It responds to all frequencies, up to about 20kHz.

The filtering is done electronically, inside the Mercruiser ECU. This way, manufacturers need to stock only one sensor, but they need to customize the electronics for each application.

Re: Programmable knock control systems
 

John,

Thanks indeed for that clarification!

What GM sensor part number, what additional hardware would I need and where would I need to install it if I wanted to add a correctly tuned knock sensor to my 496HO block?

John,

Will the J&S unit work with the Mercruiser "non-resonant frequency" knock sensors (two of them, one on each bank) or is a frequency tuned knock sensor required?

Gosh, it's been a while.

J&S units can be configured to work with either one.

I do not know why I have never seen this thread before. I have distroyed more motors then I care to remember over the years. I had bought the MSD knock sensor but it relied on me watching the lights and while running fast was the last thing I wanted watch.


GPM I know you were running a fast ecm also. Have you done anything with knock sensor's & if so, what did you get and how does it work?

Tj, I bought the J&S, just haven't installed it yet. Hoping to get to it in the spring.

Didnt Keith Black make a drill fixture for the piston oilers? Also heard the Nascar guys had it before the marine stuff. I was told it originated from Audi diesel engines.Ya hear so much now days:D

Yes it has been a while.

What is involved to configure a J&S unit to work with the Mercruiser "non-resonant frequency" knock sensors versus a frequency tuned knock sensor?

John ?

If the J&S unit works with resonant knock sensor, then it will not work with broadband sensors, because the broadband units require an ECU with Digital Signal Processing to do the filtering.

Michael

That is what I thought but I wanted to be sure. Thanks.

Doesn't post #63 above say that it works with both types of sensor?

Yes, but no explaination has been forthcoming as to how so until then................

Friend of mine used to run one of these on an F3 car. I'll do some digging if you like.

Sure if you don't mind. Not a high priority item. Just trying to learn more about these different knock warning / sensing systems.

Older units are factory set. Newer ones are adjustable.

RW? I read your last email, but it didn't click that you knew Ian.

Rage: I haven't responded, since the processors we were using are now very hard to get, though I have a contact in Asia that says they are still available.

Ian Whiteside is a calibration engineer at Ilmor Racing in the UK. He bought a system for his personal Formula 3 race car maybe three years ago. The engine is 2.0L, based on a 1.8L Eclipse engine, with 14:1 compression.

He said that with that much compression, the engine is severly knock limited, and can run no more than about 14° timing at 4000 RPM, with 98 RON fuel.

A MoTeC M400 was installed and adjusted on the dyno. Timing was optimized using knock sensing headphones, then was retarded two degrees as a safety margin.

The J&S was then installed, and timing was bumped two, four, then six degrees. The dyno operator could detect nothing more than occasional trace knock, yet the J&S was controlling timing on the knocking cylinders.

Remember, when you adjust for no knock, you are tuning to the worst cylinder, sacrificing power in the others.

Individual cylinder knock retard increases engine efficiency and power. Ian emailed that he was showing a four percent gain. Didn't sound like much to me, so I didn't bother plotting his spread sheet data for about a year. I was amazed to see the area under the curve when I did. The graph shows an eight percent gain when they switched to 102 RON, the spec fuel for his series. No other adjustments were made.

When you get to my site, click on the Vampire link, then scroll down to the dyno graph.

Yep, Ian and I both used to work together at Cosworth and then Integral before he went on to Ilmor.

Individual knock control really is the correct way to go. Certainly calibrating Bosch systems when compared to the old method of open loop spark calibrated to worst pot and then retard 3 degrees, the ability of a proper multi channel knock control system to optimise every cylinder yields significant performance advantages.

I'm sure that with in vee intercooled pre SC carbed V8s ie likelihood of significant AFR changes from cylinder to cylinder down the blower, that a proper knock control system would give a major boost, as well as piece of mind.

I'll have to dig out some in-cylinder pressure traces and FFTs for everyone's amusement at this rate.

I'll get back to you separately on that sprint car question John.

John, I guess back to my original question "What is involved to configure a J&S unit to work with the pair of Mercruiser "non-resonant frequency" knock sensors versus a single frequency tuned knock sensor?" May I assume from your comment below that the addition of a special (hard to get) processor to your basic J&S unit is required so that it will work with "non-resonant frequency" knock sensors? Would there be additional custom programing to taylor this additional processor to properly work with my unique engine or does adding the additional special processor alone produce a turnkey unit that will work properly with all "non-resonant frequency" knock sensors without any addition custom programing?

Thanks,

Bill

No, I think he's saying that the processor he uses is hard to get full stop. Irrespective of input type.

The main difference between the input stage for resonant and non- resonant is the level. Just turn the gain up. That's all there is to it.

Really. I have the general specs on my Delphi knock sensors, copy attached, but have no idea what the resonant knock sensor output versus engine vibration specification is. I am getting the impression that the resonant sensor output is low (filtered) until the "tuned resonant frequency" is reached by at which point the sensor output signal amplitude increases significantly, like a step function, and then returns to a low amplitude above the "tuned resonant frequency". Is that how it works or other?