Larry,
You’re right – the Mojos require a different setup than MGs or Bridgestones. They have a little less grip than the MGs. However, I think they’re a pretty good race tire. A new Mojo is only about .2 sec quicker than a used one, and they don’t go off until they’re completely worn out. And they don’t wear out quickly. That means you can test all day, keep making changes, and you can tell what’s working without worrying about tire degradation.
I think the Mojos will give you a chance to better show your driving skills. Some of the corners that are easy flat out on MGs require a much careful approach on Mojos. Everybody’s fast on easy corners, the better drivers will stand out in difficult ones.
Keep trying changes and you’ll get there. My kart was horrible on Saturday, but by the end of Sunday I’d picked up almost 2.5 seconds and the kart was starting to feel pretty good.
Charles