You can generate pressure with almost any defense by blitzing corners and linebackers through your gaps. If you are running 3-4 base, blitz your DT, LE, and RE, then blitz at least 2 out of your 4 linebackers. If you have defensive backs on the field, such as CBs or a safety, blitz them from the outside. They can penetrate fast from the outside with their speed. Bunch your linemen up and send them rushing, then blitz 2 linebackers in the gaps. This will cause all sorts of havoc for the opposing quarterback. Blitzing your primary corners is also a good option here and there. It can stop an outside run, and also blind-side the opposing QBs backside.
Cheers.
-eKieron