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Would a rocker hitting a retainer set off the knock sensor?

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Old Jul 27, 2003 | 02:00 PM
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PLANT PROTECTION's Avatar
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From: La Porte, IN
Car: 1987 Monte Carlo SS
Engine: L98
Transmission: 200-4R
Axle/Gears: 7.625 10 bolt/3.73s
Would a rocker hitting a retainer set off the knock sensor?

As in the title, but it is not just one, it is all 16. I am running 1.46 dual valve springs and Crane gold race rockers. While hooked up to my ALDL scanner, it reports tons of knock, mainly at low load like cruising down the road and reving in park. Would this be picked up or only combustion knocks?
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Old Jul 27, 2003 | 03:30 PM
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From: Albuquerque, NM
Car: 1966 El Camino Custom
Engine: 350
Transmission: 200R4
Axle/Gears: 3:73 12 bolt with Brute Strength
It might be picking that up. Forged pistons manufacturers warn that sometimes piston knock from cold forged pistons might be sensed by the knock sensor until the piston can reach it's working temperture and proper expansion. So yes....the sensor picks up any knocking "loud" enough to be picked up. It is not sensing unusual combustion processes, just sensing the noise.
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Old Jul 27, 2003 | 06:08 PM
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ede
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From: Jackson County
if it is or not you need to take care of your interferance problem. my guess is you have a problem with geometry. i'd also suspect it'd trip the knock senser.
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Old Jul 28, 2003 | 12:33 AM
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From: La Porte, IN
Car: 1987 Monte Carlo SS
Engine: L98
Transmission: 200-4R
Axle/Gears: 7.625 10 bolt/3.73s
Your geometry guess is most likely valid, the biggest complaint with pro topline heads. As a general statement, is this caused by too long or too short pushrods?
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Old Jul 28, 2003 | 05:07 AM
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From: Jackson County
check with the maker of your heads, but generally speaking as lift increases so does push rod length.
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Old Aug 1, 2003 | 06:14 PM
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From: La Porte, IN
Car: 1987 Monte Carlo SS
Engine: L98
Transmission: 200-4R
Axle/Gears: 7.625 10 bolt/3.73s
My pushrods were WAY long, so much for +.100 pushrods for the +.100 valves. My stock 7.195 are much closer. The interference is gone and so is the false knock, thanks guys.
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