knock parameters

contectr · Post by **contectr** » Sun Sep 13, 2009 3:58 pm

HI hondata..
how i can see if the knock are true or false knock from noise of my blower??
i have a k20a2 with jrsc and 9 psi pulley installed it...
With knock threshold , knock level..is possible to see wich type of knock is???

Post by **Hondata** » Mon Sep 14, 2009 7:47 am

Ignore the knock level and threshold - use the knock count to determine if there is knock.

Using a dyno run or acceleration run from 2000 rpm to redline in 2nd gear, see where the knock count increases. Pull put 2 degrees timing at those rpm points. If the knock count deceases, it is real knock, otherwise it is 'false knock'.

contectr · Post by **contectr** » Wed Sep 16, 2009 10:24 am

i have knock in the 2500 rpm zone and from 6500 to 7500 rpm but not in 2 gear...only in 3-4-5-6 gear!
- in the 6500-7500 rpm i have try to less ignition and i have more knock 60-70 knock...i have put ignition about 2° and the knock decrease 10 knock..
-in the 2500 rpm zone i have try to less ignition and the knock is the same..i don't have try to put ignition!!!

the af ratio is wot 11.5 read from my plx devices wideband gauge!!is too rich and the unburned fuel create knock and pre-ignition??

Ok more people speak to me about the noise of jrsc with the ep3 civic si manifold and the ghost knock!!
Is about a few days that i have remove the stock jrsc belt manual tensioner and i have modify my oem tensioner for work and the knock from 6500 rpm decrease a lot..7-6 knock

i attack the datalog and kal...my wideband voltage is in the SO2V because i don't use the secondary lambda sonde

Post by **Spunkster** » Wed Sep 16, 2009 11:27 am

sometimes increasing the timing on a vehicle with a supercharger will reduce the knock. This sounds crazy, but it is true.

contectr · Post by **contectr** » Wed Sep 16, 2009 11:34 am

Spunkster i have see it...it's crazy but really!
But now my problem is at 2500 rpm..in the power curve the car don't less power and the knock is 1-2 times..low but i want go safety because this car is my all days cars...!i have try with more dyno run on the street with high gear and more load and they knock the same

Post by **Spunkster** » Wed Sep 16, 2009 3:52 pm

You must determine if it is real knock or false knock or if it is some other mechanical noise getting picked up.

contectr · Post by **contectr** » Wed Sep 16, 2009 11:25 pm

i have try to put ignition in the colums 11-12 low cam angle 40 and lean the af ratio from 11.2 to 12.2 and they don't knock..it's possible don't like af ratio too rich at low rpm in low cam under boost ????
see the datalog is a 5 gear
What is the right AF ratio Wot for a supercharger K20 engine??more people speaks to me about 11.0 rich, other 12.0...??????

Post by **Spunkster** » Thu Sep 17, 2009 11:13 am

Mid to low 12s are good for boost

contectr · Post by **contectr** » Thu Sep 17, 2009 11:17 am

my dyno run in the street on 3rd gear are about 11.5 WOT from 3000 (vtec) to rev limit...too rich??they hurt performance and can generate knock by the unburned fuel??
I read on some forum about turbo and supercharged cars that before 11 psi are good 12.0 afr..but the Exhaust gas temperature??
i see the peolple with rsx and ep3 supercharged don't use egt..only the knock and af ratio...i thinks egt is important too for the engine stress...hot-cold...too hot in WOT!do you have any experience about this?

contectr · Post by **contectr** » Fri Sep 18, 2009 8:25 am

lean to 12.0 afr is not dangerous for the engine ??
the egt with 12:0 go too high i thinks