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Moving Knock Sensor for accuracy

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Old Nov 4, 2011 | 04:36 PM
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Moving Knock Sensor for accuracy

I was kicking around the benefit (if any) of moving the knock sensor to the rear housing. Thinking about it, the rear housing as we know runs hotter so real knock would be occuring sooner there than the front. Also, the sensor would be further away from all the engine's pulleys, belts, chains, and things that make knocking noise normally.

Just wondering if anyone has moved it and recorded the knock data differences in the rear housing....
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Old Nov 4, 2011 | 04:43 PM
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It's an interesting theory. I've debated about getting the Link Knock Block and hooking it up to a Link G4RX, but decided it probably wasn't with the effort, time and expense. Arghx, got some really interesting SAE papers regarding the OEM knock sensor and placement.
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Old Nov 4, 2011 | 06:21 PM
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Last winter my engine started showing high kock. It did it from 12 to 16 psi boost.
Running my water injection did not stop it. Even tried removing three degrees of timing along with WI, still high knock. The proof that I knew it was noise was a 16 psi run in 5th gear up to 7000 rpm with knock showing 120. No abnormal engine noise could be heard and nothing bad happened.

This summer I moved the sensor back to the rear rotor. This last cold spell in Houston did show noise in the high 50s. Have to wait until 10C for a real test.
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Old Nov 4, 2011 | 06:50 PM
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I moved mine to the rear housing for the same theory. Don't have any before and after test data, but figure the knock sensor would work best in the rear.
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Old Nov 4, 2011 | 09:08 PM
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I wish we had affordable equipment to measure combustion chamber pressure. That's the best way to determine knock. That's how the OEM's do it when they are calibrating an engine.
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Old Nov 5, 2011 | 07:16 AM
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Will the wire "reach" from the back location?
If now how did you extend it, seems like it is a shielded wire that might not be easily spliced.

thanks
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Old Nov 5, 2011 | 08:59 AM
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Originally Posted by cewrx7r1
The proof that I knew it was noise was a 16 psi run in 5th gear up to 7000 rpm with knock showing 120. No abnormal engine noise could be heard and nothing bad happened.....
Reading this is a little reassuring to me. My knock get into the 40's and low 50's regularly even at 10 to 11 psi and with WI.

But 7000 rpm in 5th? What is that, 200 mph?
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