Turning off Knock sensors

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Jun 17, 2014 | 02:29 PM

superbean

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Turning off Knock sensors

How do you guys/gals feel about turning off knock sensors? Time to time around 3500rpm or so, the car will pull back, bog down and then come alive again around 4000rpm. I used a scan tool to watch ignition timing while driving and it drops back to 8-10 degrees. I asked my tuner about the question and we believe my exhaust header is hitting the frame under hard acceleration. He said that he has also seen the issue on crummy fitting headers for Corvette and will see a "false" knock.

Setup:
Stock 5.3
220/224 cam
Longtubes all stock otherwise
Currently at around 27 deg total timing

Jun 17, 2014 | 03:57 PM

Slowhawk

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From: Bridgewater,Ma

I shut them off in my personal cars and a select few of customer cars that race a lot. If the tune is done right it shouldn't be a problem.

Jun 17, 2014 | 04:06 PM

2xLS1

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From: Warr Acres, OK

So your knock sensor tables are set up to pull 17-19 degrees of timing in PE mode?

Jun 17, 2014 | 04:18 PM

thunderstruck507

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From: Northwest AR

I would be nervous about it. I once got some really bad gas and they were working to help it before the car developed other symptoms (hesitations, bucking, audible knock ping, etc).

Jun 18, 2014 | 06:54 AM

typhoon186

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From: SC

can't you just de-sensitize them a % to reduce false knock? If the header is hitting the frame, you should be able to see where that is happening and take corrective actions.

Jun 18, 2014 | 07:50 AM

Billiumss

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From: Erie, PA

Take said car to an exhaust shop and let them fix the real problem, might be worth the $50-100.00.

Why mask the problem and if you get bad gas the PCM can't do its job.

Jun 20, 2014 | 05:54 PM

danieloneil01

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From: Dickinson, Tx

Get a grinder and jack the car up and cut that ****. Turning off the sensors is pretty dumb unless it's a race car. No gas is the same even from the same station.