Haltech j&s knock sensor
10-12-05, 07:52 PM
#16
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Are you going to run waste spark for the leading coils, and use the J&S monitor port as an input to the Haltech?
Note that the Green wire needs to see an ignition trigger every 180°, so you will need to run waste spark for the leading coils.
Note that the Green wire needs to see an ignition trigger every 180°, so you will need to run waste spark for the leading coils.
10-12-05, 08:45 PM
#17
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yea...
green wire from haltech = both leading coils in wastespark... haltech just calls it direct fire in the setup.
but just to clarify everything--one wire controls both coils.
and what if....IF we got 3 boxes? one for leading, two for trailing. as long as it's dialed in correctly, shouldn't that work?
green wire from haltech = both leading coils in wastespark... haltech just calls it direct fire in the setup.
but just to clarify everything--one wire controls both coils.
and what if....IF we got 3 boxes? one for leading, two for trailing. as long as it's dialed in correctly, shouldn't that work?
10-12-05, 09:42 PM
#18
I'm using a motec M8 and can't run split on my 20b. It ran fine when I was in Japan at 578rwhp but just recently it started making me wonder. Would the J & S unit be worth investing in?
-Destin
-Destin
10-12-05, 11:56 PM
#19
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Originally Posted by John at J&S
RETed: Thanks for the props with respect to our Honda unit, but I don't know why you feel it's your duty to bash the RX7 version every chance you can. Why not state just state it's limitations, and how to make best use of it?
Nothing more, nothing less.
People seem to think it's some wonder box that would miraculously work with the stock RX-7 ignition system - the below info was not available back then (this was like 5+ years ago!).
I didn't even know there was an "RX7 version" - or are we talking about the single-channel version?
We've been making units for the RX7 since '92. Back then, no one was narrowing the split, so it wasn't an issue. Now that is, take the limitations into account, and use the J&S intelligently. Limit the split to no less than 10°, and set the J&S for 10° max knock retard.
If desired, the units can be reprogrammed to select either 5° or 10° max knock retard, instead of the stock 10° or 20°.
Is this something that can be done on earlier manufactured units?
If this is not acceptable, why not try feeding the J&S display voltage into an unused analog port on the Haltech, and use it as an auxilliary retard. Then the Haltech can retard both plugs.
When used this way, no wires need cutting. Leave the J&S White disconnected, and splice the J&S Green trigger wire to the leading coil igniter input signal.
The monitor jack is 3.5mm stereo. The signal is on the terminal defined as "Ring", and varies from 0 to 1.3v. "Tip" and "Sleeve" are 12v and Gnd to power the optional bargraph display.
If the unit is set to retard individual rotor faces (S2 down), the monitor voltage could change with each spark event, reflecting the amount of retard for the face that just fired. Don't know how fast the Haltech can react, so you may want to set S2 up. In this mode, the monitor voltage can change once every three revolutions (one engine cycle).
When used this way, no wires need cutting. Leave the J&S White disconnected, and splice the J&S Green trigger wire to the leading coil igniter input signal.
The monitor jack is 3.5mm stereo. The signal is on the terminal defined as "Ring", and varies from 0 to 1.3v. "Tip" and "Sleeve" are 12v and Gnd to power the optional bargraph display.
If the unit is set to retard individual rotor faces (S2 down), the monitor voltage could change with each spark event, reflecting the amount of retard for the face that just fired. Don't know how fast the Haltech can react, so you may want to set S2 up. In this mode, the monitor voltage can change once every three revolutions (one engine cycle).
I love your products (have one myself), but after seeing one bad experience, it leaves a bad taste in my mouth.
I've since disconnected the ignition function and run it purely as a knock monitor.
For the $500 I paid for it, it's a very expensive knock monitor!
-Ted
10-12-05, 11:57 PM
#20
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Originally Posted by GUITARJUNKIE28
it wasn't the j&s... i'd say it was the tuner.
You really want me to start bashing your ****?
-Ted
10-13-05, 12:45 AM
#21
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CLR (Carlos Lopez Racing) used to run a J&S with zero split on his distributor car. In fact, he's the one who asked me to design a unit for the Rotary.
He called here one time after running the unit for a while, and said "this thing is worth $800 to $1000." He said the performance was night and day, compared to the MSD BTM's he had been using.
Haven't talked to him since '94, when we had a dispute over another product.
He called here one time after running the unit for a while, and said "this thing is worth $800 to $1000." He said the performance was night and day, compared to the MSD BTM's he had been using.
Haven't talked to him since '94, when we had a dispute over another product.
10-13-05, 01:18 AM
#22
Originally Posted by John at J&S
CLR (Carlos Lopez Racing) used to run a J&S with zero split on his distributor car. In fact, he's the one who asked me to design a unit for the Rotary.
He called here one time after running the unit for a while, and said "this thing is worth $800 to $1000." He said the performance was night and day, compared to the MSD BTM's he had been using.
Haven't talked to him since '94, when we had a dispute over another product.
He called here one time after running the unit for a while, and said "this thing is worth $800 to $1000." He said the performance was night and day, compared to the MSD BTM's he had been using.
Haven't talked to him since '94, when we had a dispute over another product.
Anyhow I've been using John's products since the beginning on both piston and rotaries and have always got good results. Every rx-7 I build and tune must have one. The idea of using the output of the J&S to a stand alone have been done before. Some people even got little boxes made to trigger relays,circuits etc. based on knock. I've seen one that cut power to the boost controller in the event of knock.
Most people still believe that ignition retard on a rotary is going to stop knock. It's not!
Here's a little clue to what helps a lot. The first thing the human mind does after hearing knock is to lift the right foot. Why not use the power and speed of the ECU to do the same. It's much faster than the brain most of the times
With that said figure out which program or programs in your stand alone ECU best suit the need. I have!
Last edited by crispeed; 10-13-05 at 01:26 AM.
10-13-05, 01:25 AM
#23
Originally Posted by John at J&S
RETed:
The monitor jack is 3.5mm stereo. The signal is on the terminal defined as "Ring", and varies from 0 to 1.3v. "Tip" and "Sleeve" are 12v and Gnd to power the optional bargraph display.
.
The monitor jack is 3.5mm stereo. The signal is on the terminal defined as "Ring", and varies from 0 to 1.3v. "Tip" and "Sleeve" are 12v and Gnd to power the optional bargraph display.
.
What's the output level of the unit when the 1st Led on the monitor lights up?
10-13-05, 01:35 AM
#24
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RETed: I guess this is where the misunderstanding started.
The difference between the Honda unit and the RX7 unit is primarily in software, relating to the engine cycle.
The RX7 version was always single channel, retarding only the leading plug, unless you ran zero split with a distributor. I have a three channel version in the works, but can't say when it will be finished. I'm in the process of switching all my designs to a newer Motorola processor, so it will be a while.
The cycle for a piston engine is two revolutions, compared to three revolutions for a rotary. To keep track of the knock in each rotor face, I programmed the knock detector as a six "cylinder", that fires every 180°.
I don't know why the engine blew on the dyno. It may have gone lean, and went into pre-ignition. Pre-ignition means the mixture went off before the spark, so retarding the timing further won't help.
Normal detonation happens at about 45° ATDC on a Rotary, so we have a knock "window" set up in software to listen at that crank angle. Pre-ignition happens at a different crank angle, before the spark event. Since spark retard cannot stop pre-ignition, we don't listen for it.
Bob Norwood called me a couple of years ago. He said, (paraphrasing) "I don't know you and have never bought anything from you, but I've had some high horsepower RX7's come through my shop, and we're talking 600hp, and the ones that live on the dyno have one of your units installed." Then he went on to tell me that he was tuning a Motec for a Honda race team, and thought it might be a good idea to get one and play with it.
The difference between the Honda unit and the RX7 unit is primarily in software, relating to the engine cycle.
The RX7 version was always single channel, retarding only the leading plug, unless you ran zero split with a distributor. I have a three channel version in the works, but can't say when it will be finished. I'm in the process of switching all my designs to a newer Motorola processor, so it will be a while.
The cycle for a piston engine is two revolutions, compared to three revolutions for a rotary. To keep track of the knock in each rotor face, I programmed the knock detector as a six "cylinder", that fires every 180°.
I don't know why the engine blew on the dyno. It may have gone lean, and went into pre-ignition. Pre-ignition means the mixture went off before the spark, so retarding the timing further won't help.
Normal detonation happens at about 45° ATDC on a Rotary, so we have a knock "window" set up in software to listen at that crank angle. Pre-ignition happens at a different crank angle, before the spark event. Since spark retard cannot stop pre-ignition, we don't listen for it.
Bob Norwood called me a couple of years ago. He said, (paraphrasing) "I don't know you and have never bought anything from you, but I've had some high horsepower RX7's come through my shop, and we're talking 600hp, and the ones that live on the dyno have one of your units installed." Then he went on to tell me that he was tuning a Motec for a Honda race team, and thought it might be a good idea to get one and play with it.
10-13-05, 01:49 AM
#25
''Pre-ignition means the mixture went off before the spark, so retarding the timing further won't help.''
Pre-ignition I believe is what is responsible for most of the blown up rotaries. Even the ones with the perfect tune can't compensate for any type of pre-ignition.
''Spark retard cannot stop pre-ignition.''
I'm in total agreement and have said this time and time again.
Pre-ignition I believe is what is responsible for most of the blown up rotaries. Even the ones with the perfect tune can't compensate for any type of pre-ignition.
''Spark retard cannot stop pre-ignition.''
I'm in total agreement and have said this time and time again.
10-13-05, 02:06 AM
#26
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crispeed: 1.3v/10 LED's equals 0.13v per LED.
It sounds like you might be lowering the boost, a la the Saab APC, also known as "automatic gas pedal". Saab's tech paper said this method is safer than spark retard, since it doesn't raise exhaust valve temps.
The Saab paper also hinted at EMI problems (electrical interference from the spark plugs), so I doubt if they got knock retard working reliably. Of course, this was back in the early '80's.
I bought my first knock sensor from a Saab dealer in '83, and started experimenting. At the time, I was buildng boost retard units for AK Miller and Kas Kastner. I had mine on the market before MSD, must have been in '81. Ak put one on his propane turbo Ford, and it made the cover of Hot Rod.
Dr. Jacobs (CompuSpark, etc.) and Bill Hayes (Stinger Ignitions/Centerforce Clutches) both called me the day it hit the stands. We had Bill over for dinner, and showed him my home lab. I guess he wanted to see if I was a threat or not. He told me, NOBODY goes into his lab except his engineer. Dr. Jacobs didn't get an invite, though one of his spys made it in later.
It sounds like you might be lowering the boost, a la the Saab APC, also known as "automatic gas pedal". Saab's tech paper said this method is safer than spark retard, since it doesn't raise exhaust valve temps.
The Saab paper also hinted at EMI problems (electrical interference from the spark plugs), so I doubt if they got knock retard working reliably. Of course, this was back in the early '80's.
I bought my first knock sensor from a Saab dealer in '83, and started experimenting. At the time, I was buildng boost retard units for AK Miller and Kas Kastner. I had mine on the market before MSD, must have been in '81. Ak put one on his propane turbo Ford, and it made the cover of Hot Rod.
Dr. Jacobs (CompuSpark, etc.) and Bill Hayes (Stinger Ignitions/Centerforce Clutches) both called me the day it hit the stands. We had Bill over for dinner, and showed him my home lab. I guess he wanted to see if I was a threat or not. He told me, NOBODY goes into his lab except his engineer. Dr. Jacobs didn't get an invite, though one of his spys made it in later.
10-13-05, 02:21 AM
#27
Originally Posted by John at J&S
crispeed: 1.3v/10 LED's equals 0.13v per LED.
It sounds like you might be lowering the boost, a la the Saab APC, also known as "automatic gas pedal". Saab's tech paper said this method is safer than spark retard, since it doesn't raise exhaust valve temps.
The Saab paper also hinted at EMI problems (electrical interference from the spark plugs), so I doubt if they got knock retard working reliably. Of course, this was back in the early '80's.
I bought my first knock sensor from a Saab dealer in '83, and started experimenting. At the time, I was buildng boost retard units for AK Miller and Kas Kastner. I had mine on the market before MSD, must have been in '81. Ak put one on his propane turbo Ford, and it made the cover of Hot Rod.
Dr. Jacobs (CompuSpark, etc.) and Bill Hayes (Stinger Ignitions/Centerforce Clutches) both called me the day it hit the stands. We had Bill over for dinner, and showed him my home lab. I guess he wanted to see if I was a threat or not. He told me, NOBODY goes into his lab except his engineer. Dr. Jacobs didn't get an invite, though one of his spys made it in later.
It sounds like you might be lowering the boost, a la the Saab APC, also known as "automatic gas pedal". Saab's tech paper said this method is safer than spark retard, since it doesn't raise exhaust valve temps.
The Saab paper also hinted at EMI problems (electrical interference from the spark plugs), so I doubt if they got knock retard working reliably. Of course, this was back in the early '80's.
I bought my first knock sensor from a Saab dealer in '83, and started experimenting. At the time, I was buildng boost retard units for AK Miller and Kas Kastner. I had mine on the market before MSD, must have been in '81. Ak put one on his propane turbo Ford, and it made the cover of Hot Rod.
Dr. Jacobs (CompuSpark, etc.) and Bill Hayes (Stinger Ignitions/Centerforce Clutches) both called me the day it hit the stands. We had Bill over for dinner, and showed him my home lab. I guess he wanted to see if I was a threat or not. He told me, NOBODY goes into his lab except his engineer. Dr. Jacobs didn't get an invite, though one of his spys made it in later.
I still have one of the early units with the adjustable pot on the bottom that I bought form Carlos way back in the early 90's. Still kicking ***.!
''Automatic gas pedal''
Now that's a great name for it!
''AK Miller and Kas Kastner''.
Have not heard those names in a long time. The early turbo gurus. Ak was the 'suck through'(draw through) king. Corky 'blow through' king is young compared to those two!
10-13-05, 06:04 AM
#28
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Originally Posted by John at J&S
The difference between the Honda unit and the RX7 unit is primarily in software, relating to the engine cycle.
The RX7 version was always single channel, retarding only the leading plug, unless you ran zero split with a distributor.
(...)
The cycle for a piston engine is two revolutions, compared to three revolutions for a rotary. To keep track of the knock in each rotor face, I programmed the knock detector as a six "cylinder", that fires every 180°.
The RX7 version was always single channel, retarding only the leading plug, unless you ran zero split with a distributor.
(...)
The cycle for a piston engine is two revolutions, compared to three revolutions for a rotary. To keep track of the knock in each rotor face, I programmed the knock detector as a six "cylinder", that fires every 180°.
I don't suppose you remember all the units ordered?
This was an order for three units that went to Hawaii...
I don't know why the engine blew on the dyno. It may have gone lean, and went into pre-ignition. Pre-ignition means the mixture went off before the spark, so retarding the timing further won't help.
It was out of my control.
I think the FD was running a Pettit "Unlimited" ECU at the time.
It wasn't a stand-alone, and I wasn't responsible for the car at that point in time.
Thanx for offering such detailed information.
I know you got better things to do than argue with a bunch of online idiots.
-Ted
10-13-05, 08:04 AM
#29
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While I have two Haltechs on stand by I currently have the J&S with PFC...I assume as a moniter. I must say it's great to have John providing a rare product insight and addressing issues that we need to now as owners and my self as a laymen.
Thanks
Thanks
10-13-05, 08:14 AM
#30
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RETed:
I was always confused, when you would post that I had no idea how an RX7 ignition works. I finally had to go off on you, just to get my post count into double digits.
I do vaguely remember shipping three early RX7 units to Hawaii. Seems like you had to have them on a Saturday for a dyno session? About all I can remember.
The black box versions were fixed at 20° knock retard range, so that engine may have run into a negative split issue.
I don't know if I have a copy of the early software. It was on a hard drive that crashed. If you have a version made before '95, I may not be able to change the knock retard range.
I was always confused, when you would post that I had no idea how an RX7 ignition works. I finally had to go off on you, just to get my post count into double digits.
I do vaguely remember shipping three early RX7 units to Hawaii. Seems like you had to have them on a Saturday for a dyno session? About all I can remember.
The black box versions were fixed at 20° knock retard range, so that engine may have run into a negative split issue.
I don't know if I have a copy of the early software. It was on a hard drive that crashed. If you have a version made before '95, I may not be able to change the knock retard range.
Last edited by John at J&S; 10-13-05 at 08:43 AM. Reason: more info