Is the ring supposed to mount on the same keyway as the crank sproket? It has a shortened keyway on it that doesnt extend out past the crank sproket so the balancer hub will mount all the way down. Is this right?

I was told that this sensor is only used to detect misfires. If so can I leave it off?

Thanks

 

Why are you trying to put one on a 1995?

 

It's for my friends 97. Im putting his together while he is at USMC recruiting school in Cali.

 

It would have been nice to include that info originally.:blah:

Is the engine you are putting together using all the original parts? Sounds like you have a pre 96 crank key. It is shorter than the 96-97 ones and won't stick out to catch the reluctor for the CPS. How about the hub? Is it for a 93-95 or 96-97? They are different lengths.

If you leave the reluctor off, you will get a SES from the CPS not functioning.

 

We are using the 97 hub from his orignal motor. I guess he got the wrong crank key cause it doesnt stick out past the crank sproket. He partially put the motor together before he left and now I'm finishing it up for him. Can I use a standard halfmoon crank key for this or is it a special configuration?

Thanks Shoebox

Just for my own knowledge, what does this sensor do? I mean I understand the basics but what does the pcm use this info for?

 

The CPS is for misfire detection. On 96 and 97 LT1s with OBD2, the computer can read the CPS and the position of the cam and determine which cylinder is misfiring so it can tell you exactly which one is giving you a problem. Are you using a stock timing chain with this motor?

BTW, if you leave out the reluctor ring, you will need a spacer of equal thickness (about .100"). You can get one from ATI since they make a universal kit for LT1s. Or you can use a pre 96 crank hub.

 

It is a special cut back key, so the hub does not interfere with it. (If you had a keyed hub, you could use a regular key)

The CPS is there to measure crank velocity and compare it to what the opti sees. It's mainly used by OBD-II to detect misfires. In extreme cases (and with the proper scan tool) you can use the readings to detect timing chain stretch (little known fact ).

Most other cars that have a CPS, actually use it for spark timing info and wont run without it. The LT1 gets it's spark timing info from the opti.

 

Man, I wonder what my CPS would have said about my stock chain. It had some play in it.

Shoebox, did you ever get your maro running?

 

Oh yeah. Been back on the road since the 1st of February. All back to normal.

 

I was shooting for April Fools day for mine, but I didn't quite make it.

 

Thanks everyone. Now I just hope the local dealership has one in stock They really are worhtless