in the two cars i mentioned, it really is just a case of gearbox adjustments, them being barely legal road cars anyway.
as far as i recall, the F1 set it's record on 'standard' tyres (whatever they were) without even needing adjustment to its pressures; that's why i said out of box.... but then again, i also seem to recall that it did have its ratios re-jigged so maybe not so 'out of the box'....