I did a FAQ on this topic last year:
===================
Here is what the factory parts guide has listed for cams for various [ years:
[ 1987 ]
4293 817 CAMSHAFT PACKAGE, w/Standard Journals (Except EDG Turbo
& EDR Turbo-Intercooler Engine)
Consists of:1-----Camshaft, 8-4173390 Rocker, Valve
4293 818 CAMSHAFT PACKAGE, w/.050 O/S Journals (Except EDG
Turbo & EDR Turbo-Intercooler Engine)
Consists of: 1-----Camshaft, w/.050 O/S Journals (Stamped O/S J)
8-4173390 Rocker, Valve
4293 819 CAMSHAFT PACKAGE, w/Standard Journals (w/EDG Turbo,
w/EDR Turbo-Intercooler Engine)
[ 1988 ]
4387 850 CAMSHAFT, w/Standard Journals and EDF Injection Engine
4387 850 w/Standard Journals and EDG Turbo, EDR Turbo-Intercooler
Up to 3-1-88
(Notice that in this year the TBI and turbo I and II applications use the same cam up through 3/1/1988)
4387 721 w/Standard Journals and EDG Turbo, EDR Turbo-Intercooler
After 3-1-88
[ 1989 ]
4387 850 CAMSHAFT, w/Standard Journals (Exc. EDR Turbo-Intercooler)
(Notice in this year the cam for the TBI car is the same as for last year, but the turbo cam is now different)
4387 721 w/Standard Journals (w/EDR Turbo-Intercooler)
4448 479 w/.050 O/S Journals (Exc. EDR Turbo-Intercooler)
[ 1990 ]
4387 850 CAMSHAFT, w/Standard Journals (Exc. EDR Turbo-Intercooler)
(Notice in this year the cam for the TBI car is the same as for last (89)year, and the turbo cam is also different but the same cam as it was in 89)
4387 721 w/Standard Journals (w/EDR Turbo-Intercooler)
4448 479 w/.050 O/S Journals (Exc. EDR Turbo-Intercooler)
[ 1992 ]
S/C EDF - 2.2L Eng. andard" Camshaft Package for Service.
S/C EDR - 2.2L Eng (Turbocharged-Intercooler) andard" Camshaft Package for Service.
4387 850 CAMSHAFT, w/Standard Journals
4448 479 .050 O/S Journals
(Notice that it's back to the same cam for both EFI as well as turbo cars)
So based on this information, my theory is that an 89 CSX came with cam #4387 850 which is the same cam as found in any 88 TBI car or turbo car manufactured before 3/1/1988, any 89-90 TBI car, or any 92 TBI or turbo car.
NOTE: Sorry I didn't have the parts book for 91 cars so it is not included here.
The best old cam was the 430 lift 240 duration 85' cam, but it is a slider cam, not a roller.
Then the roller cam out, with valve timing for square tooth pulleys
turbo was a 430 / 228 cam
TBI was a 430 / 238 cam
So by getting the 88 TBI you basically got the 85 turbo cam in roller form and the right valve timing. Which is an issue with adding a round tooth cam to a square tooth engine as the 4 degrees difference hurts power. With a 88 TBI cam in a later car the advance timing gives a little more power. When running big boost with stock crap like a one piece the pressure differential kills you so the TBI has made more power than the S60 at 25 PSI. If you do a plenum you can run more cam, if you are running a little mitsu run the stock roller turbo cam because of excess backpressure.
If you want to use a later TBI on a log engine get advanced timing keys or adjustable gear.
===================