Nitro has excellent G's through the Helix. On X-Flight, the G's were very powerful, but both time I went on, the loop didn't really affect me! Only the turn right after the loop and the final helix really push you out and into the harnesses!
Anyway, the most painful G's I have ever experienced were on 2 coasters...they were clones. They are known as Shockwave at SFGAm and Great American Scream Machine at SFGAdv. After the double loop element, you rise up very quickly into the brake run while turning to the left. If you are siting in the front, you get EXTREME negative G's. Just so you guys know, too many negative G's are also very painful. These rides pull too many negative G's. All of the blood rushes to your head VERY quickly and I grey out everytime I ride in the front. When I ride in the back, the rest of the train has already slowed from the brakes, so you don't get the negative G's as much, but in the front it is very painful.
I am very tolerant to G's on coasters, but Nitro, X-Flight, Shockwave, and GASM have all gotten me. Nitro and X-Flight didn't hurt...they were very enjoyable, but Shockwave and GASM hurt!
Also, B&R: TC pulls great G's in the cobra roll. The Batman side also pull good G's in the pull into the top hat.
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Gone, a sense of confidence, I'm convinced that there's just too much pressure to take! - Linkin Park, Crawling
KoЯn still Яules!