Proper methos to decrease knock?
Proper methos to decrease knock?
Can anyone tell me the proper way to fix persistant knocking. I managed to stop knocking in cylinder 1 but all others continue. I've tried and tried but still knocking. Knock about 9-12 times on a short drive (10 minutes). Almost always knocks around 2500-3500RPM. Also cylinder 2, I've retarded ignition all the way to -5 degrees! but that seems excessive. Should I adjust ignition first then fuel, vice versa, if fuel at all. I have Injen SRI and greddy Evo2 catback. Thanks.[/b]
Without seeing a calibration and datalog it is hard to say what you should do. I'm guessing that you've trimmed one cylinder by -5 degrees, not reduced the overall timing to -5 degrees.
You should never need to retard the ignition more than about 3-4 degrees total - if you retard this much, and still get knock, start looking for other causes. Typically it is a mechanical issue - often with the exhaust header making noise.
Fuel does not make much difference to knock - ignition timing is the best way to tune out knock.
Do a datalog with no additional ignition retard. Do another datalog with the ignition reduced by 2 degrees, using the same driving cycle. If you get the same knock, then it is mechanical, otherwise it is knock. A SRI will cause knock with heatsoak - the stock airbox will out-perform SRIs when the hood is closed.
You should never need to retard the ignition more than about 3-4 degrees total - if you retard this much, and still get knock, start looking for other causes. Typically it is a mechanical issue - often with the exhaust header making noise.
Fuel does not make much difference to knock - ignition timing is the best way to tune out knock.
Do a datalog with no additional ignition retard. Do another datalog with the ignition reduced by 2 degrees, using the same driving cycle. If you get the same knock, then it is mechanical, otherwise it is knock. A SRI will cause knock with heatsoak - the stock airbox will out-perform SRIs when the hood is closed.
Hondata
if your having problem with knock rethink your ignition tables. also take a look at ur af's. wht is ur af at when knock occurs? another precaution is to run higher octane we should be running at least 91 i run 93 just to be safe and have had no problem with knock. knock is heat and compression causing fuel to preignite. think opposition more fuel cools and helps you burn all oxygen in mixture. trial and error