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lateshow
04-04-2011, 07:25 PM
Just came up with this wild theory having seen the difference between evo 5 and 6 knock detection system. Evo 6 seems to be a lot more eager to detect knock. I've been datalogging facelifts and prefacelift and facelifts tend to knock more. Could it be possible that knock detection on facelifts has different parametres?

Any ideas? Kenneth? Anyone?

Wodjno
04-04-2011, 08:34 PM
Just came up with this wild theory having seen the difference between evo 5 and 6 knock detection system. Evo 6 seems to be a lot more eager to detect knock. I've been datalogging facelifts and prefacelift and facelifts tend to knock more. Could it be possible that knock detection on facelifts has different parametres?

Any ideas? Kenneth? Anyone?

Are these stock FL & PFL's? Remebering FL's run more boost !

lateshow
04-04-2011, 09:08 PM
No stock :) Just facelifts and prefacelifts in general running similar boost pressures throughout the rpm range. For instance a -97 manual could easily do 12 Psi (maximum for not flashed ecu) with stock ignition and ECU hears no knock. Than a -01 A/T Legnum was getting knock readings generally over 10, biggest was around 20, with stock ignition and 12Psi. I had to retard it quite a bit and still it keeps knocking. With headphones I can only hear sometimes 2-4 but not every time and the car says ~10.

I'm thinking the difference could be 7203FA vs 7202F because the first one seems to have more knock. Tough to say. :)

Nick Mann
04-04-2011, 09:11 PM
Swap the ECU's between the cars and see if it helps?

lateshow
04-04-2011, 09:35 PM
Yes, could be one solution to test this, my suspect is that ecus with EM2428 or/and 7203FA tend to have more knock. First 7202F models with for example EM2005 don't knock that much.

Kenneth
04-04-2011, 09:45 PM
I wouldn't be surprised if this is the case. Especially if Mitsubishi have done it with other platforms.

If I get the chance I can disassemble an earlier ECU and take a look. It isn't high on my priority list though, so it could be a while away.

lateshow
05-04-2011, 09:00 AM
I wouldn't be surprised if this is the case. Especially if Mitsubishi have done it with other platforms.

If I get the chance I can disassemble an earlier ECU and take a look. It isn't high on my priority list though, so it could be a while away.

Nice! Nobody has yet discovered parametres for knock detection for vr4 so it could be about time :)

disco-ian
02-08-2012, 10:44 AM
Just been reading this thread.

Are there any reasonably priced units that show levels of knock from the stock knock sensor.

I know there is a Kenneth MOD to the later ECU's to use the engine check light to show levels of knock but is there a aftermarket gauge to do this? And if not what levels does the modified rom show.

Ian

Davezj
02-08-2012, 01:33 PM
the modified rom can show whatever level you set it to.
there is a single element table in the rom that if you put 3 in it the erngine warning will flash when 3 knocksum counts and above are detected. this happens to be the default setting. but you could set it to anything you want from 1 to 36 (36 is the max knock count recordable).

Nick Mann
02-08-2012, 02:53 PM
I think there is little point seeing the raw data from the knock sensor. Knocksum is calculated from the raw data as far as I know, so I assumed it was that calculation that Lauri was querying rather than the sensor itself.

There is a bit of kit called a knocklink that detects knock and displays it, but I am 90% sure it uses it's own sensor. You can use Evoscan to display the knocksum from the ecu, but I'm not sure that is a solution you want?

disco-ian
02-08-2012, 11:04 PM
It sounds like my real solution is going to be to track down a cheap later date ECU rather than the 7201 that I have, so that I can run the modified ROM to show knock and to run modified map etc.

There seem to be lots on eBay that have black plugs on but with silver cases. Anyone know what ECUs these are as they do not fall into a category in the Modding FAQ thread.