Pelican Parts Forums - J&S knock sensor location?

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J&S knock sensor location?

So I am debating where to mount a single knock sensor on my 1986 930.
What have other people done to mount one? I don't want to drill the heads for knock sensor bridges.
Back in the day, I added one to my Saab 99 turbo and adapted the later 16 valve SAAB APC system to my early 8 valve B motor..... That was a long time ago and not really germane to this discussion.

http://forums.pelicanparts.com/uploa...1675819013.jpg

This is a convenient spot, but would require trimming the long leg of the throttle bracket.

http://forums.pelicanparts.com/uploa...1675819220.jpg

The fit of the throttle shaft is nearly perfect with these bushings, but I am slightly concerned that if worn the movement of the shaft may cause a vibration picked up by the knock sensor...
In an ideal situation there would be a boss here somewhere I could just bolt the knock sensor to. Probably over thinking this.
David

I used that same location and its picking up knocks just fine, but I'm using a headset to physically hear it rather than connecting it to the ECU for knock control.

Ok, that's great news. It would really be tough to move this once installed
David

http://forums.pelicanparts.com/uploa...1675869250.jpg

This is where I installed mine. Drilled and tapped hole - just don't go too deep. Haven't had a chance to try it yet though -

I spent a lot of time looking into the Safeguard and read quite a few threads. I didn't have my engine apart and was reluctant to drill/tap any holes. One solution I saw from another member was using the breather cover. Some SCs, Carreras, and later 930s had a hole for a sensor in the opposite side from the breather - I think it's M14x1.5, but could be a size bigger or smaller, or you could drill/tap another hole in the cover if the hole in question is being used for a sensor.

I think a "special" bolt was needed from McMaster to use the Bosch knock sensor - I'm sure there's a name for the type of bolt, but was essentially an M14 bolt with a smaller female threaded portion in the head. Basically a thread adapter, I guess.

You screw the bolt into the breather cover then screw the appropriate (smaller) bolt for the knock sensor into the female threads in the head of the bolt that goes into the breather cover.

Quote:

Originally Posted by sigchuck (Post 11917798)

I thought about that location before deciding to install it beneath the throttle bracket, the only thing is that piece is isolated by a gasket to the engine block, which may absorb/alter some if the knocking sound, while I got my intake off I went a head and installed a second knock sensor in to that location just to do A/B test to figure out the difference, of course still havent got the time to that test.