That is going to be more a function of the printer file you are using. There are PAGESIZE settings associated with each externally described printer file that, in conjunction with the LPI, CPI and OVERFLOW will allow you to print just about any size page imaginable. By default this is typically set to 66 lines, 6 lines to the inch (11 inch page) with overflow at line 60 allowing for a 1 inch margin at the bottom. The 132 characters across with 10 char to the inch will give you 13.2 inches across. You will need to change or create a printer file with settings equal to 8.5 x 14. To get the 8.5 across, 85 characters with 10 to the inch or 102 by 12, etc. To get the 14 inches top to bottom, 84 lines by 6 LPI, or 112 lines by 8 LPI, etc.
If you are using a default print file such as QPRINT, where other programs use the print file and you do not want to change their appearance, you can use the OVRPRTF command to change these settings within the scope of the job.
Additional tip: When playing with these settings, I often set the page rotation (PAGRTT) to 0.