My understanding is that side exhausts must exit the side of the vehicle a certain minimum distance behind the rearmost opening window and also on the RHS of the vehicle.
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My understanding is that side exhausts must exit the side of the vehicle a certain minimum distance behind the rearmost opening window and also on the RHS of the vehicle.
also a certain distance from the last door seal on the side.
from about 80 all exhausts either went out the back or to the right so you couldnt smoke up the pedestrians.
I'd say that it is a self regulation thing, you send in a letter and they send back another letter telling it is ok to print the compliance plate.