Alcohol/E85 knock detection methods
#1
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How is everyone detecting knock?
With just det headphones its really hard to tell, does anyone have some good clear recording as examples?
Is knock windowing accurate with alcohol and good enough?
I have just pulled the head off a car running 11.2:1, 25psi, and 20* timing with no signs of knock, but when I tuned it it was so hard to be sure.
Thanks,
Dann
With just det headphones its really hard to tell, does anyone have some good clear recording as examples?
Is knock windowing accurate with alcohol and good enough?
I have just pulled the head off a car running 11.2:1, 25psi, and 20* timing with no signs of knock, but when I tuned it it was so hard to be sure.
Thanks,
Dann
#3
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It shouldn't be hard to tell unless the car is straightpiped or something. If it's unclear, improve the quality of the headphones or go to a mechanical set (nylon hose from the engine block to your ear).
#4
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Thanks andrew, Ive never heard knock on alcohol, and all of the more experienced tuners near me claim that its almost impossible to hear, can you point me to any recordings, or does it truly just sound like gasoline?
Thanks,
Dann
EDITED: Used australian terminology
Thanks,
Dann
EDITED: Used australian terminology
Last edited by nitrodann; 05-06-2015 at 01:55 AM.
#7
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As for how to tune it if it's knock limited, I'd say use det cans, with either a dyno, a drag strip, datalogs on a long road, something to compare power to see how much timing helps power.
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