occasionally missing car names from Series pages

[popmonkey]

Describe the bug
Series pages are sometimes missing the car name next to the car class.

To Reproduce
Steps to reproduce the behavior:

visit https://json.racing/irs/series/5914/

Screenshots

[popmonkey]

this is due to how iRacing manages car restrictions in the API.

they are per car class but iRS is filtering the complete car list.