L67 Knock Sensors

[CTX-SLPR]

Anyone see a problem with this setup? I really don't want to be drilling holes into water on the sides of the block.

[Eddie-98GTP]

I understande, I wouldn't either. Although it isn't ideal (but then again what is?), I think you'll be fine like that.

[CTX-SLPR]

That picture is a photoshop, I've not made any holes yet. Judging by research on other GM knock sensor configurations in "legacy" engines it looks like the sensors don't have to be centralized to do thier job. The LT1 even has a single sensor located on 1 side of the engine in the old drain hole. The OBDII version has a pair, one on each side but they aren't between the center 2 cylinders. It would seam that the whole block would ring with the sound of detonation if it occured and the side to side is more for amplitude rather than bank to bank location. I could be wrong. I'll probably start with this setup and if its proving to not be sensative enough I'll look into relocating the sensors to the water jackets out of the way of the headers but away from the timing chain.

[Russ K]

1999 Buick Regal GS, trying to figure out if the fuel pump, fans, and the AC clutch go through the engine harness block or one of the other 2 blocks.

Here are the diagrams from my ALLDATA.

Russ Kemp

[Phantom]

CTX I cant personally help you but if anyone knows a good locations on the block to place the knock sensor it would be Turbocharged400sbc here is a post i had saved by him.

http://www.3800pro.com/forum/general...sii-heads.html

I believe he uses the same name on www.bonnevilleclub.com and clubgp.com.

[CTX-SLPR]

Yeah, I asked him on clubgp about relocating it due to his 4T80E experiments.

[CTX-SLPR]

I got an answer from an unusual place. I was talking to a Grand National vendor about fuel pressure regulators and Coil On/Near Plug Ignition systems and randomly I mentioned the twin knock sensors on the L67 and how I'd have to drill the rear webbing for another because no one was sure about having bank to bank KR. The answer is that its impossible to have bank to bank on a wastespark since the ICM has no idea what bank you are on. So I'm going to measure the resistance of the stock knock sensor and then wire an inline resistor in the second spot and call it good.

[Eddie-98GTP]

I got an answer from an unusual place. I was talking to a Grand National vendor about fuel pressure regulators and Coil On/Near Plug Ignition systems and randomly I mentioned the twin knock sensors on the L67 and how I'd have to drill the rear webbing for another because no one was sure about having bank to bank KR. The answer is that its impossible to have bank to bank on a wastespark since the ICM has no idea what bank you are on. So I'm going to measure the resistance of the stock knock sensor and then wire an inline resistor in the second spot and call it good.

Not to add confusion, but the knock sensors don't go to the ignition module, and the PCM does know which cylinder is firing...

[CTX-SLPR]

Good catch. However with a waste spark system the ECM can't pull by bank since both primary and waste plug fire at the same time and the ECM isn't setup for sequencial ignition.

[Eddie-98GTP]

Good catch. However with a waste spark system the ECM can't pull by bank since both primary and waste plug fire at the same time and the ECM isn't setup for sequencial ignition.

Good point! Either way, I believe you'll be fine with the one sensor.