There are lots of opinions on Lucas and other stabilizers. There is a guy who actually did a series of tests using Lucas as opposed to conventional oil with some rather shocking findings. I'll try to google it in a second.

Why are you wanting to use it anyway? Are you having a leak or smoking problem? I also have a 4 cyl LE (03) but will never use Lucas in the car. I just use a semi synthetic blend and try to keep the engine bay as clean as possible just incase any leaks do come up. When it does leak, just replace the seals or gaskets responsible.