Making Your Kicks Sound Tight

Ok here's a cool trick :

If everything fails use your beats signal to trigger a sine wave tuned around 90hz... your beats will sound huge now.

You do this using noise gates and sidechain processing, (the beats signal into the gate's sidechain to trigger the sine wave) this trick is very effective and it sounds different than the usual Eq boost....

Or you can try boosting the lower range with the eq around 40-60 hz ?
also try adding a gentle boost around 160-250 hz...
keep in mind that the low mids and the lows are kind of special... too much can make your beats sound boxy but then sometimes boxy is what you want...

The sound you'll get will be on the clean side because a sine wave is a pure tone with practically no harmonics, so if you use a clean beat you'll get a clean sound....if you use a dirty beat you will get the dirty beat plus clean low end.
Be aware that distortion will change your perception of loudness; even if it's not too loud in the mix, fat beats sometimes use a little distortion but in a way that is not obvious...