Jump to content

High Altitude CPS vs. Regular CPS?


Recommended Posts

i actually compared the two in a non- quantitative way just last week-  both were new. Since i have a 4.0 2wd auto it takes minutes to swap them out and after drilling out the  mounting holes as recommended in the renix tips swapped the two and compared the general idle quality and acceleration about the hood sort of method - I found  the HA to give a slightly better  idle , acceleration was hard to say but certainly was no worse with the HA CPS so i went with it -  i would of liked to compare them on some hills to see if there was a discernible difference, but i'm happy i  went with the HA one

Link to comment
Share on other sites

I've been running one in my '88 Cherokee for fifteen years. I'm basically at sea level -- you will NOT see any difference in performance, but if you drive gently you will see an improvement in gas mileage.

 

All the high altitude CPS does is allow the timing to advance a bit farther. But when you drive peddle to the metal, the engine is always at the point of detonation and the knock sensor is controlling how far the timing can advance -- so under heavy load or heavy acceleration, the knock sensor overrides the CPS and doesn't allow that extra 2 degrees of ignition advance to kick in. Where it does become operative is at cruise throttle.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...