Mini me,
Our stock truck class is not 'box stock'. I wrote the classes down in haste, and sometimes my scribeling is difficult to make out...

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It is same as stock buggy...Kit motor and 6 cell 2/3 a pack. We do run Mini ts with 18ts. But only because we get from 0 - 1 mini-t per race day! Indeed, they should be in seperate classes, if you have enough racers & time for the additional classes. The Mini-t can be competetive against the 18t or the Xray truck, it takes a lot of set-up work though. This only applies to small carpet tracks... The high grip levels the playing field. Mini-t main problem is horrible steering geometry. Once you have that worked out so it handles as it should, it runs quite well against the 18t.
When you have a fairly small track and room for only 20 to 30 racers, you have to be practical in your class offerings.
Offering more classes to improve fairness and broader appeal, is another reason for seperating on & off-road days.