Knock Knock Safe effective boost for 89 octane?
10-12-2005, 03:51 PM
#16
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Originally Posted by Zero10
Evan70, the output of the knock sensor looks rather like static to the untrained eye from what I have read, it's not a simple yes/no type of thing.
10-12-2005, 04:35 PM
#18
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"You can run more than 12psi on 87 octane, especially with our low compression ratios, and with the stock chips, they're tuned pretty conservatively."
Then to run the magical "1 BAR" no one really needs to run chips. Just stick with stock chips and a MBC , 93 octane and you are good to go.
Then to run the magical "1 BAR" no one really needs to run chips. Just stick with stock chips and a MBC , 93 octane and you are good to go.
10-12-2005, 04:40 PM
#19
Three Wheelin'
Pin 15 doesnt go to the DME. It goes to some diagnostic plug under the dash. Before I crashed my car(s) I was going to long the signal coming from this line and see what it actually was during knock, but I never got around to it. Someone do it so we dont have to buy anything!
The DME never knows if the car is knocking, the timing impulse goes through the klr and is retarded if necessary there.
The DME never knows if the car is knocking, the timing impulse goes through the klr and is retarded if necessary there.
10-12-2005, 04:59 PM
#20
Three Wheelin'
I get knock at anything over atmospheric pressure when I run 87. As soon as I put 93 in, no more knock. I don't know how you guys are running ~12psi on 87 with no knock. Maybe the 87 around me is really low quality.
10-12-2005, 05:36 PM
#21
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Ok, I'm going to go ahead and tap into pin 15 and monitor. Can't hurt anything, as my SBC will handle any voltage signal that it might send. It may be a few days before I get around to it, but I'll post the results once I get it done.
10-12-2005, 08:28 PM
#22
Race Car
mike murcia, I just can't understand how that happens. Our engines are 8.0:1 compression ratio, if you got knock at atmospheric intake manifold pressure, then the N/A guys should always get knock at WOT with their 9.6:1 - 10.9:1 CR's. Yet I was just fine with 87 (and once 85) octane in m 86 N/A...
I didn't know that pin 15 was different. Neat-o.... this may be helpful!
I know how to make my car knock, but I'm not sure I want to do that just to find out what that pin does.
But yeah, I know you won't get knock with 87 octane and stock chips (in a properly running unmodified engine), and I'll prove it
My stock chips just came in the mail today, so once my engine is together, I plan to run nothing more than 87 octane, and perhaps some injector cleaner.
I didn't know that pin 15 was different. Neat-o.... this may be helpful!
I know how to make my car knock, but I'm not sure I want to do that just to find out what that pin does.
But yeah, I know you won't get knock with 87 octane and stock chips (in a properly running unmodified engine), and I'll prove it
My stock chips just came in the mail today, so once my engine is together, I plan to run nothing more than 87 octane, and perhaps some injector cleaner.
10-12-2005, 09:57 PM
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Originally Posted by fast951
You want to detect knock WAY before you can hear it.. The KLR has some nice software and filtering mechanism for knock detection.. The beauty of the KLR is that the code is for our engine!! The bad think about the KLR is the lack of "notification".. We are developing a "Knock Display" which will read the data from the KLR and will make it available as a 0-5V signal and a bar graph.. Will be released soon after the Wasted Spark..
10-13-2005, 12:52 AM
#25
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Originally Posted by hally
sounds like a very useful product, how much do u think it will be John?
10-13-2005, 10:06 AM
#26
Race Car
Not trying to bash you or anything Mike, but it would have to be incredibly lean. My 86 N/A ran with AFR's in the 16's quite often under WOT (had very plugged fuel injectors) and I never saw knock. IMO that's getting extremely lean, and things worked okay, except for how slow it was. I don't know just how lean it would have to get to see knock with 87 octane, an 8.0:1 CR and reasonable ambient temps, but I suspect it would have to be lean enough that the car just won't run right anyways.
I know a lot of people don't believe my statements about 87 octane, and there's really no solid way to convince people. However, I myself am convinced, and that's good enough for me (obviously). I will be going over the intake/exhaust once more, making sure there are no leaks (post-reassembly), installing the stock chips, and running 'er on 87 octane from when I get it back together, untill the car and I part ways. (Unless I crank up the boost, chip it, or bump up the CR of the motor, that changes everything)
I know a lot of people don't believe my statements about 87 octane, and there's really no solid way to convince people. However, I myself am convinced, and that's good enough for me (obviously). I will be going over the intake/exhaust once more, making sure there are no leaks (post-reassembly), installing the stock chips, and running 'er on 87 octane from when I get it back together, untill the car and I part ways. (Unless I crank up the boost, chip it, or bump up the CR of the motor, that changes everything)
10-13-2005, 10:48 AM
#27
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"Not trying to bash you or anything Mike, but it would have to be incredibly lean. My 86 N/A ran with AFR's in the 16's quite often under WOT (had very plugged fuel injectors) and I never saw knock. IMO that's getting extremely lean, and things worked okay, except for how slow it was. I don't know just how lean it would have to get to see knock with 87 octane, an 8.0:1 CR and reasonable ambient temps, but I suspect it would have to be lean enough that the car just won't run right anyways."
Your fogetting timing. I would assume we have more advanced timing then the NA at LESS then atmospheric.
Your fogetting timing. I would assume we have more advanced timing then the NA at LESS then atmospheric.
10-13-2005, 11:08 AM
#29
Race Car
Originally Posted by Mike Murcia
I'm not sure Zero. Maybe the car is running very lean around atmospheric pressure?
10-13-2005, 11:14 AM
#30
Three Wheelin'
My car is chipped a la Guru. With all the talk about how he could minimize lag via running lean before boost sets in, I assume Dan made tining more agressive also. I don't know for sure. What I do know is that when I run 87 and the boost tips in, there is a distinct "nut in a coffee can" sound that is never present when I run 93.