BlazinT/A

iTrader: (10)

i need a little help under standing the gm reluctor ring, i wanted to use an lsj(sc cobalt ss) pcm to power a turbo mazda engine. my question is what do each of the rings do is the signal split or does it read as a whole? what does each ring do?

it looks as if the lsj uses the same design for reluctor and sensor as the ls1 and also is 58x like later ls engines

joecar

There are two reluctor rings: CKP (crank position) and CMP (cam position).

CKP indicates crank position.
CMP indicates which 360° phase of the 720° cycle the crank is at.

GenIII (LS1):
CMP is 1x
CKP is 24x, it has 24 x 15° segments;
each 15° segment is further divided into 12°/3° sub-segments;
each 90° sector has a different pattern/permutation of sub-segments (allows the PCM to know where the crank is within the first 90° of rotation).
More info:
GenIII CKP/CMP waveforms
GenIII CKP/CMP description

GenIV (LS2/3):
CMP is 4x
CKP is 58x (more precisely 60-2x, i.e. 60x with 2 missing teeth);
all the teeth are uniform (on shutoff the PCM counts how many teeth go by before crank stops).

LS1 is very different from LS2/3.

I don't know what the LSJ uses.

BlazinT/A

iTrader: (10)

Thanks that link is exactly what i needed

BlazinT/A

iTrader: (10)

does anyone happen to have the dimensions of the ring? inner diameter and outer diameter. i can pick one of these up for $17 just want to know if it is going to be worth it.