The suggestions above are good. Here are a couple of other things to think about:
1) it would be prudent to check your enlarger's light source. If, for example, the bulb is wrong or there is some cyan filtration that is not moving out of the way when you use the white light setting, there may be too much green light hitting the paper and therefore reducing the contrast;
2) light sources with dichroic filters are really nice to use, so if you have one that is working well, you may appreciate the flexibility it offers. You don't really need to calibrate the source, unless you are trying to match previous work. What you need to do is use the Ilford link above to get a reasonable idea of the range, and then become familiar with how it performs, so you can use it reliably in the future. The numbers themselves don't matter, it is the correlation between the settings and how you perceive the results;
3) it is possible that your desire for high contrast relates mostly to how you see the prints - you may prefer something like the "soot and chalk" look as compared to something with fine tonal gradation. If that is the case, you will need both contrastier negatives and high contrast enlargement filters/settings. I looked at the one enlargement you posted in the APUG gallery and its contrast looks fairly normal. Does it look low in contrast to you?