As I recall, various pumps put out differing amounts of pressure. Most Mopar boxes put out between 900 PSI and 1300 PSI, the higher the PSI the less effort it will take to turn the wheel. Great at low speeds but at high speeds this leads to less "road feel."

Big Block Dart has an article on the various pumps and pressures used by Mopar. You can read the article here:

http://www.bigblockdart.com/techpages/pspumps.shtml

Most GM pumps put out between 800 PSI and 1000 PSI, thus if you have a mopar box with 900 PSI you're probably pretty close, though the steering might be a little lighter.

If the steering is too light, or you wish to be able to adjust the level of effort in your steering, you can install an adjustable power steering valve from Heidts Hot Rods.

You can find it here:

http://www.heidts.com/steering_kits_components.html

Hope this helps,

Regards,

Joe Dokes