Yep Red spring performs most duties,but, it took me a while to try out the other Springs cos I got lazy,LOL....Thats why I believe it could take months to try out all possibilities.Off the top of my head, I am pretty sure I use between 4.5-6.5, depending on the Job I was doing, the Spring I was running, and the Speed I needed, the throw/Piston will also affect the Gas/V's so the answer is in there somewhere,P.