Knock counting, What's good
12-03-2007, 02:13 PM
#136
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To resurect an old thread
I think I have figured out a way to distinguish low load knock vs knock at high boost pressures.
I have installed another Hobbs switch that when about 12psi (availible in adjustable pressure values) sends the 12 volts to activate the counter, otherwise it is not on and not detecting knock. Then I also have a toggle that will power the switch to see what the counts were during the run.
I thought I would share this info for those who are not using a piggyback and cannot log the counts accurately.
I also use E85 and see very few counts at high boost.
I think I have figured out a way to distinguish low load knock vs knock at high boost pressures.
I have installed another Hobbs switch that when about 12psi (availible in adjustable pressure values) sends the 12 volts to activate the counter, otherwise it is not on and not detecting knock. Then I also have a toggle that will power the switch to see what the counts were during the run.
I thought I would share this info for those who are not using a piggyback and cannot log the counts accurately.
I also use E85 and see very few counts at high boost.
Rogue
01-03-2008, 12:45 PM
#138
Three Wheelin'
awsome thread! i just installed my counter- 701 model- i was wondering if there is ANY way to reset it. I thought by reading that it didnt have a spot to put a button to reset it but that turning the ignition or power off would reset it. It seems that after testing mine- turning by boost up some to get alittle more chance of detonation- and getting on it on the backroads by my house i got 36 counts of knock. I unplugged the thing and did a final install, then when i fired it back up still had the same # showing! Most of these were while i was just pulling away from a stop sign or something w/ a low load- no biggie. Anyway, see how you like my slick install- i still have all the OE parts in a box should i decide to swap back be asured.
- sorry for the crappy pics its dark in my garage currently and my camera doesnt like night pics much.
- sorry for the crappy pics its dark in my garage currently and my camera doesnt like night pics much.
Okay Dan you have inspired me to build one into the same spot. I cut my counter open and found that it's missing a little SMT resistor that connects the reset pin to the circuit. By carefully soldering in a resistor, you can make it resettable. I have a broken digital clock on the way from a rennlister and will build mine into it, and hopefully tap into one of the clock buttons for a reset switch. If anyone's interested I'll post a couple of pictures when it's done. An easier way to go if you don't need the plastic enclosure is to buy one of these resettable counters- http://search.digikey.com/scripts/Dk...me=267-1011-ND (You didn't think I figured out the missing resistor on my own, did you?
)I also am seeing a few counts per gear at WOT at 15 PSI, although I can't hear any knock. It seems to me that the knock probably isn't hurting anything if it can't be heard, but if it's enough to cause timing to be pulled, it's robbing power, right? Since it hasn't been determined how many counts per time period it takes for the KLR to pull timing, does anyone know of a way to figure out when timing is being pulled and by how much, so that it can be correlated to the knock counts?
I asked John at Vitesse about logging pin 15 with my SMT-6, and he said he hasn't looked closely at what pin 15 outputs. Apparently there is an internal variable that the DME looks at in the KLR for pulling timing, which may or may not correspond exactly to pin 15. I would like to monitor pin 15 with my SMT-6 but it sounds like the pulse width is too narrow. Maybe the signal can be run through a little circuit that would convert the spikes into a long enough pulse that it could be seen with the SMT-6?
It seems to me that there are some pretty important unknowns with this, mostly how many counts per WOT are safe, and when timing is pulled.
07-24-2008, 10:53 PM
#140
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Hey What's Going on with this thread?
Great Thread! How about updates? I have a Matco hand held ignition lab scope that I can use while running down the road. If I had a counter I could see the timing being pulled at what knock count. And could measure voltage and freq from pin 15 at same time. 4 channel scope, and can see 6 functions at one time.
Neal
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05-15-2009, 11:43 AM
#142
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I bought the parts to make two of these knock counters. Hooked up one and installed it on my car on Tuesday. After some runs I am seeing at 16 or 17lbs boost a knock or two on a WOT run. At 18 or 19lbs boost I am getting 4 or 5 knock counts.
When I get a chance I am going to hook this up to Brad's (ilikemy944) completely stock car and see what sort of knocks he gets.
When I get a chance I am going to hook this up to Brad's (ilikemy944) completely stock car and see what sort of knocks he gets.
05-15-2009, 02:55 PM
#145
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I bought the parts to make two of these knock counters. Hooked up one and installed it on my car on Tuesday. After some runs I am seeing at 16 or 17lbs boost a knock or two on a WOT run. At 18 or 19lbs boost I am getting 4 or 5 knock counts.
When I get a chance I am going to hook this up to Brad's (ilikemy944) completely stock car and see what sort of knocks he gets.
When I get a chance I am going to hook this up to Brad's (ilikemy944) completely stock car and see what sort of knocks he gets.
05-15-2009, 03:04 PM
#146
Burning Brakes
Thread Starter
That's interesting. I have continued to have boost problems for years and have effectively given up.
My car stock, would put out many knock events during a run, and thousands during a race weekend. I find that with my car the highest count will be if you use a high gear, low revs (ie below 3,000RPM) and then plant the throttle. As soon as boost comes on it counts like hell. I have tried every new part, many times, and have never been able to change anything.
It will be interesting to see what you get with a stock car.
My car stock, would put out many knock events during a run, and thousands during a race weekend. I find that with my car the highest count will be if you use a high gear, low revs (ie below 3,000RPM) and then plant the throttle. As soon as boost comes on it counts like hell. I have tried every new part, many times, and have never been able to change anything.
It will be interesting to see what you get with a stock car.
05-15-2009, 03:08 PM
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I can't get the car to knock on typical lugging situations (shift into 5 when going 20) but I do notice when I am coming up to a turn and downshifting - working my way through the intersection I might get counts. Of course that is all at low rpms with no load on the engine.
05-15-2009, 03:10 PM
#148
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That's interesting. I have continued to have boost problems for years and have effectively given up.
My car stock, would put out many knock events during a run, and thousands during a race weekend. I find that with my car the highest count will be if you use a high gear, low revs (ie below 3,000RPM) and then plant the throttle. As soon as boost comes on it counts like hell. I have tried every new part, many times, and have never been able to change anything.
It will be interesting to see what you get with a stock car.
My car stock, would put out many knock events during a run, and thousands during a race weekend. I find that with my car the highest count will be if you use a high gear, low revs (ie below 3,000RPM) and then plant the throttle. As soon as boost comes on it counts like hell. I have tried every new part, many times, and have never been able to change anything.
It will be interesting to see what you get with a stock car.
Is there such thing as a light knock or a hard knock or are they all about the same intensity?
05-15-2009, 03:17 PM
#149
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This is with the MAF and on pump gas. I think Quiktrip - whatever their highest grade it (93 I think).
I can't get the car to knock on typical lugging situations (shift into 5 when going 20) but I do notice when I am coming up to a turn and downshifting - working my way through the intersection I might get counts. Of course that is all at low rpms with no load on the engine.
I can't get the car to knock on typical lugging situations (shift into 5 when going 20) but I do notice when I am coming up to a turn and downshifting - working my way through the intersection I might get counts. Of course that is all at low rpms with no load on the engine.
05-15-2009, 03:25 PM
#150
Race Car
I think Rogue is working with someone using a stock car and a knock counter with some timing variation?? You may want to PM him.
Myself I am still only seeing 1 max in a single gear pull. (This is w/o the hobbs switch activation)
I will get a couple just pulling out of the driveway and a couple taking off from a light and some bs low load counts.
I was working on a new configuration so I elected to leave the pressure threshold out of the equation and man it racks em up much quicker. It went from a count of less than 200 to many thousand since. I will be wiring the pressure and activation (power supply) back up shortly and getting another counter.
Myself I am still only seeing 1 max in a single gear pull. (This is w/o the hobbs switch activation)
I will get a couple just pulling out of the driveway and a couple taking off from a light and some bs low load counts.
I was working on a new configuration so I elected to leave the pressure threshold out of the equation and man it racks em up much quicker. It went from a count of less than 200 to many thousand since. I will be wiring the pressure and activation (power supply) back up shortly and getting another counter.