Adding knock sensor to 86.5
10-21-2006, 08:07 AM
#1
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Adding knock sensor to 86.5
I took my car to a local hotrod show. It really attracted alot of attention. I met a guy there that specializes in turbocharging and supercharging RX 7's. He has a nice shop with RX-7's from all over the country. He offered to help me fine tune my car to get the most out of my Twin Screw. One of his first questions was if I had a knock sensor. He suggested a Haltech engine management system that has the capability to get input from a knock sensor. Has anyone ever added a knock sensor to an early 32 valve engine? Is it possible?
10-21-2006, 10:08 AM
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I think two sensors are needed if one wants to know in which cylinder knock is happening. S4 and later have two so that ECUs can adjust each cylinder individually.
10-21-2006, 11:07 AM
#3
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The Porsche system also needs the Hall sensor to be able to determine which cylinder is knocking, as well as the 2 knock sensors.
If you run a simple sytstem with one sensor, which cannot determine which cylinder is detonating, then you will have to retard all cylinders at the same time by the same amount, so you will loose out big time.
Would you have to completely remap the fuel and igntion if yuou swap to a Halteck ? This is quite a bit task.....
If you run a simple sytstem with one sensor, which cannot determine which cylinder is detonating, then you will have to retard all cylinders at the same time by the same amount, so you will loose out big time.
Would you have to completely remap the fuel and igntion if yuou swap to a Halteck ? This is quite a bit task.....
10-21-2006, 12:21 PM
#4
"If you run a simple sytstem with one sensor, which cannot determine which cylinder is detonating, then you will have to retard all cylinders at the same time by the same amount, so you will loose out big time."
Technically you don't need a second knock sensor to determine which cylinder is knocking, nor
do you need the Hall sensor. The second knock sensor just improves the ability of the knock system
to discriminate noise versus an actual knock.
Technically you don't need a second knock sensor to determine which cylinder is knocking, nor
do you need the Hall sensor. The second knock sensor just improves the ability of the knock system
to discriminate noise versus an actual knock.
10-21-2006, 01:18 PM
#6
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I think each cylinder has a secret knock so you can tell which one wants to come in. In other words:
1: tap-tadap-tap
2: taptapt tap-tadaptap ...
You get the picture
1: tap-tadap-tap
2: taptapt tap-tadaptap ...
You get the picture
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10-21-2006, 02:35 PM
#8
"I think each cylinder has a secret knock so you can tell which one wants to come in. In other words:
1: tap-tadap-tap
2: taptapt tap-tadaptap ..."
Expected as much from an IDIOT or an ape! Back to the jungle please.
1. ANY location of a knock sensor will generate a signal, but its relative level will vary based on its
location and the ability of the knock system to accurately discriminate the signal from noise is reduced.
2. ANY engine management system (ECM) can EASILY determine the RELATIVE position of the knock
as the ECM "listens" for the knock after it fires each cylinder.
Idiot posts NOT welcome!
1: tap-tadap-tap
2: taptapt tap-tadaptap ..."
Expected as much from an IDIOT or an ape! Back to the jungle please.
1. ANY location of a knock sensor will generate a signal, but its relative level will vary based on its
location and the ability of the knock system to accurately discriminate the signal from noise is reduced.
2. ANY engine management system (ECM) can EASILY determine the RELATIVE position of the knock
as the ECM "listens" for the knock after it fires each cylinder.
Idiot posts NOT welcome!
10-21-2006, 02:40 PM
#9
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Originally Posted by Lorenfb
"I think each cylinder has a secret knock so you can tell which one wants to come in. In other words:
1: tap-tadap-tap
2: taptapt tap-tadaptap ..."
Expected as much from an IDIOT or an ape! Back to the jungle please.
1. ANY location of a knock sensor will generate a signal, but its relative level will vary based on its
location and the ability of the knock system to accurately discriminate the signal from noise is reduced.
2. ANY engine management system (ECM) can EASILY determine the RELATIVE position of the knock
as the ECM "listens" for the knock after it fires each cylinder.
Idiot posts NOT welcome!
1: tap-tadap-tap
2: taptapt tap-tadaptap ..."
Expected as much from an IDIOT or an ape! Back to the jungle please.
1. ANY location of a knock sensor will generate a signal, but its relative level will vary based on its
location and the ability of the knock system to accurately discriminate the signal from noise is reduced.
2. ANY engine management system (ECM) can EASILY determine the RELATIVE position of the knock
as the ECM "listens" for the knock after it fires each cylinder.
Idiot posts NOT welcome!
10-21-2006, 02:57 PM
#10
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Originally Posted by Lorenfb
Expected as much from an IDIOT or an ape! Back to the jungle please.
, a separate community from other P car owners, because we have a sense of humor 
10-21-2006, 02:59 PM
#11
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Thanks Doz, Vilhuer, John Speake, Lorenfb and heinrich for the replies. John, how is the Shark Tuner project for early 32 valve cars going? If it will be finished soon I would probably just get an LM-1 for now and wait. How would the Shark Tuner recognize detonation on the earlier cars without the sensors? Lorenfb, my tuner guy mentioned the same thing you did. He would install a knock sensor (even if it had to be epoxied to the block) and program the Haltech accordingly. He said it would be better than no knock sensor at all. heinrich, you are hilarious as usual. I cracked up laughing and get a kick out of your sense of humor. Don't stop. Can't be serious about this stuff. It's just a car. Like the ricer kid at the car show called it. "A Bad *** Car".
10-21-2006, 03:31 PM
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Originally Posted by Pizza
....... He would install a knock sensor (even if it had to be epoxied to the block) and program the Haltech accordingly. He said it would be better than no knock sensor at all. .....
I think you can use the same knock sensors & mounting points for the knock sensor/s as the S4 uses as all 928 blocks seem to have the same cast in threaded holes , maybe use 2 & wire them in together to the Haltech unit & yes any knock sensor is way better than not having one
10-21-2006, 06:09 PM
#13
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Hi Pizza
We are working on the 85/86 US LH2.2 ECU first. It will be several months before a Sharktuner for that is done.
We haven't even started to consider the EZK for these earlier cars.....but clearly a knock control system is highly desirable.
We are working on the 85/86 US LH2.2 ECU first. It will be several months before a Sharktuner for that is done.
We haven't even started to consider the EZK for these earlier cars.....but clearly a knock control system is highly desirable.
10-21-2006, 09:09 PM
#14
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When (OK, if), I boost my 86.5, I would install something like this:
I think since the coil drivers are external, a two channel (two coils) 'T1', would work.
Originally Posted by J&S
Using a single knock sensor, the system detects the onset of detonation and retards the timing on a per cylinder basis. A mode switch lets you select a maximum of either ten degrees or twenty degrees of knock retard.
10-22-2006, 12:08 PM
#15
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Originally Posted by Lorenfb
"I think each cylinder has a secret knock so you can tell which one wants to come in. In other words:
1: tap-tadap-tap
2: taptapt tap-tadaptap ..."
Expected as much from an IDIOT or an ape! Back to the jungle please.
1. ANY location of a knock sensor will generate a signal, but its relative level will vary based on its
location and the ability of the knock system to accurately discriminate the signal from noise is reduced.
2. ANY engine management system (ECM) can EASILY determine the RELATIVE position of the knock
as the ECM "listens" for the knock after it fires each cylinder.
Idiot posts NOT welcome!
1: tap-tadap-tap
2: taptapt tap-tadaptap ..."
Expected as much from an IDIOT or an ape! Back to the jungle please.
1. ANY location of a knock sensor will generate a signal, but its relative level will vary based on its
location and the ability of the knock system to accurately discriminate the signal from noise is reduced.
2. ANY engine management system (ECM) can EASILY determine the RELATIVE position of the knock
as the ECM "listens" for the knock after it fires each cylinder.
Idiot posts NOT welcome!