high altitude crank position sensor

Sometime ago I remember seeing something on here about a high altitude crank position sensor for 87-90 4.0L's. My '89 is originally from VA and I live in Denver now so I thought maybe I ought to look into getting one of those. When I called my dealer today, he didn't know anything about it. Does anyone know if such a part exists and what benefit it would provide to get one?

TIA

Don

Well... if you're calling a dealer in Denver, they won't stock the other one (it's not called high altitude here...)

Best bet is to ask for the guy to inspect the part - ask if the pick-up is centered on the mounting plate or off-set slightly toward one side...

The centered CPS is the "low-altitude"one while the off-set unit will provide you the advance...

High Altitude Crank Sensor

I have a high altitude crank sensor on my 88 xj. Its true that the pickup is offset. I am near sea level and noticed a slight performance gain.