Knock despite good afrs, conservative ign
09-24-07 | 08:42 PM
#26
Thread Starter
face crunch
Joined: Mar 2003
Posts: 280
Likes: 0
From: Shreveport, LA
If I look at averages, they show insignificant knock values. Is this the way everyone looks at knock when logging?!?!
If so, I'll just take a valium and relax
.-S
09-25-07 | 01:07 AM
#27
Banned. I got OWNED!!!
Joined: Mar 2001
Posts: 2,306
Likes: 1
From: lebanon
Start off on chart mode and scan you log for decent vehicle speed 3rd gear or higher runs, make a note of the air temp, water temp, even fuel temperature, AFR ign L and split, then tell us the instant knock level at that point..... If you hvae knock in certain conditions then you have knock
you dont need it to happen 10 times to take an average of it 
BUT you do need to qualify that it is happening at the correcthigh demand conditions and you can only see this in chart view.... sorry if I have typed out what you already know?logging vehicle speed is a good one once you set up your chart to be viewing friendly you can quickly zoom into the points of interest then blitz it for the information your looking for to analyse, if you have a log file (with these variables turned on) send it to me and I will print it in my chart view set up with corresponding map watches and post up a screen shot for you.
^wooops shoudhave checked first page ! lol will download and have a look for you should post back in a few days
09-25-07 | 01:29 AM
#28
Banned. I got OWNED!!!
Joined: Mar 2001
Posts: 2,306
Likes: 1
From: lebanon
Ok I looked at all of the logs !
Some are very bad.....
to help fault find I'd like you to put in some higher quality fuel, either a bit of race gas on top of your normal amount or a bit of tolulene to lift up the octane level then do another test run log it and post back?
the knock is in sync with high power 5500rpm onwards, on some logs its only present at 6200rpm in a spike then others I saw it carried all the way through to redline, it def deserves further investigation and analysis. The octane increase is simple and cheap, if that does not fix it then i would look towards borrowing another knock sensor and changing the one you have and if it still persists then its a process of elimination, start by putting in a fresh set of spark plugs i.e. do all the basic things you can to try and eliminate it (yes the spike values).
**Its def there some times then not looking over your info, could be fuel quality related, but to eliminate that I'd change plugs first, then sensor second, then fuel last of all** there is a couple of things i can tell you about tune if all else fails but will do that over PM only
Some are very bad.....
to help fault find I'd like you to put in some higher quality fuel, either a bit of race gas on top of your normal amount or a bit of tolulene to lift up the octane level then do another test run log it and post back?
the knock is in sync with high power 5500rpm onwards, on some logs its only present at 6200rpm in a spike then others I saw it carried all the way through to redline, it def deserves further investigation and analysis. The octane increase is simple and cheap, if that does not fix it then i would look towards borrowing another knock sensor and changing the one you have and if it still persists then its a process of elimination, start by putting in a fresh set of spark plugs i.e. do all the basic things you can to try and eliminate it (yes the spike values).
**Its def there some times then not looking over your info, could be fuel quality related, but to eliminate that I'd change plugs first, then sensor second, then fuel last of all** there is a couple of things i can tell you about tune if all else fails but will do that over PM only
Last edited by RICE RACING; 09-25-07 at 01:52 AM.
09-25-07 | 10:08 AM
#29
"Elusive, not deceptive!”
Joined: May 2007
Posts: 930
Likes: 13
From: Slidell, LA
On the example I was only trying to show the fast way to take a degree out of the hot cell.
I had just switched over from AFR, changed decimal places, the 16 AFR ceiling to 160, but missed the switch to min.
The reason for dragging the cursor line and watching the map watches allows you to analyze more than one aspect at once. For instance you will notice on the example log that just before the highest knock recorded it had gone lean during boost-up. Possibly adding fuel in this area might be the solution rather than retarding ignition. By dragging the cursor you will find that you may have multible hits in one cell. Try it.
I had just switched over from AFR, changed decimal places, the 16 AFR ceiling to 160, but missed the switch to min.
The reason for dragging the cursor line and watching the map watches allows you to analyze more than one aspect at once. For instance you will notice on the example log that just before the highest knock recorded it had gone lean during boost-up. Possibly adding fuel in this area might be the solution rather than retarding ignition. By dragging the cursor you will find that you may have multible hits in one cell. Try it.
09-25-07 | 06:32 PM
#30
Thread Starter
face crunch
Joined: Mar 2003
Posts: 280
Likes: 0
From: Shreveport, LA
Ok I looked at all of the logs !
Some are very bad.....
to help fault find I'd like you to put in some higher quality fuel, either a bit of race gas on top of your normal amount or a bit of tolulene to lift up the octane level then do another test run log it and post back?
the knock is in sync with high power 5500rpm onwards, on some logs its only present at 6200rpm in a spike then others I saw it carried all the way through to redline, it def deserves further investigation and analysis. The octane increase is simple and cheap, if that does not fix it then i would look towards borrowing another knock sensor and changing the one you have and if it still persists then its a process of elimination, start by putting in a fresh set of spark plugs i.e. do all the basic things you can to try and eliminate it (yes the spike values).
**Its def there some times then not looking over your info, could be fuel quality related, but to eliminate that I'd change plugs first, then sensor second, then fuel last of all** there is a couple of things i can tell you about tune if all else fails but will do that over PM only
Some are very bad.....
to help fault find I'd like you to put in some higher quality fuel, either a bit of race gas on top of your normal amount or a bit of tolulene to lift up the octane level then do another test run log it and post back?
the knock is in sync with high power 5500rpm onwards, on some logs its only present at 6200rpm in a spike then others I saw it carried all the way through to redline, it def deserves further investigation and analysis. The octane increase is simple and cheap, if that does not fix it then i would look towards borrowing another knock sensor and changing the one you have and if it still persists then its a process of elimination, start by putting in a fresh set of spark plugs i.e. do all the basic things you can to try and eliminate it (yes the spike values).
**Its def there some times then not looking over your info, could be fuel quality related, but to eliminate that I'd change plugs first, then sensor second, then fuel last of all** there is a couple of things i can tell you about tune if all else fails but will do that over PM only
RICE,
Thanks for looking things over! The runs I posted were with toluene added to 93 octane, which didn't seem to change the knock values much. I changed plugs to fresh 9's all around a few days ago, and this seems to have helped....no knock at all under boost, but this was without datalogging (just looked at peaks on Commander). I'll see about getting another knock sensor and trying that, as this is an intermittent problem. The runs I posted represented about 20% of my logged runs, and the others had no significant knock events under the same conditions. I won't have time to log runs until the weekend, thanks to work
.-Stew
10-06-07 | 10:09 AM
#31
Thread Starter
face crunch
Joined: Mar 2003
Posts: 280
Likes: 0
From: Shreveport, LA
I logged 10 3rd gear runs at WOT to redline, and max knock was 17. The runs were made going up a pretty steep incline, so I'm sure the load was more than adequate. This is on the same Toluene-spiked tank of fuel, same new plugs, same boost, same water injection. 
I think I'll refill the tank w/ fresh 93 octane (from a different gas station) and log a few more runs. Report to follow....
-Stew
I think I'll refill the tank w/ fresh 93 octane (from a different gas station) and log a few more runs. Report to follow....
-Stew
Thread
Thread Starter
Forum
Replies
Last Post
jetlude
Single Turbo RX-7's
4
08-18-15 04:53 PM
