I increased the air pressure to 34psi, but I can really tell much difference.

How can you determine the ratio on a rack? If I can improve that, that would be a big help.

As far as the caster, I originally set everything to MII specs. I can't recall what those numbers are at the moment, but I'll find out what kind of caster it was.

I also checked, and my steering whell is already a 14", and there aren't many out there over 15" for an application like this. Seems like I'd have to get a 16" to make it worth it.