Anyone have any info on how the crank sensor measures the position of the crank? Is it something special on the bottom crank gear ??

I'm trying to figure out a way to use a 96 cover and crank position sensor to use it to give the signal to my gen 7 dfi ecm. I am using a hd Mezziere so I am going with a custom billet core timing set and don't know if the LTX crank gear is any different. I know the cam gear is different because it has the water pump drive.

 

It uses a reluctor ring. However, on the '96, the CPS is *only* used to determine misfire. It's done by measuring the acceleration and deceleration of the crankshaft. With a misfire, there is more deceleration than expected due to a dead cylinder.

All the cylinder & timing calulations are handled by the Opti. The disk that is read by the optical sensor has varying size windows to determine crank position.

Here's a photo of the reluctor ring in mine....

 

I think the Cloyes 9-3157 timing set will work with the reluctor ring, but you'll need to get a 96 damper hub or shave 1/8" off an earlier hub.

I think what you really want to know is how the reluctor ring's edges are timed relative to the cylinder's TDC. I've wondered that too. The crank key falls in the middle edge of one of the reluctor edges, which I'd guess is probably aligned to #1 TDC, but I'm not sure. I have a spare engine in the garage and had been meaning to check that, but It's too cold out there to play at this time of year.

I've never understood why they added that reluctor. Everything they needed to know was availible from the opti's high resolution output. All they needed to do was divide that pulse train down and they would have had the same signal that came out of the reluctor sensor without adding all the new parts.

If I were trying to get a crank trigger setup going, I'd take the opti signals and use a programmable controller to generate the missing tooth type pulse train. If you wanted to do it mechanically using the reluctor timing cover and sensor, I'd get a gear from Boston Gears with the right diameter and pitch, and machine the bore and broach the keyway with the correct timing relitive to #1 TDC. The dimensions on the stock reluctor are 4.000" OD, .430" total depth, and .125" thick at the center where the well is machined to clear the damper hub.