Typically it involves tubing placement, tubing diameter, and tubing thickness. As far as leeway "NONE" either it's right or it's wrong and a chassis inspecter will not be bashful about telling you. Now going through tech is a little different, sometimes if something is wrong (depending on whats wrong) they will allow you to race but get it resolved before racing again. The chassis certs. are good for 3 years.
TS1955