in the UK you could probably just (and only just) get away without a FMIC, however it wouldnt be good for your engine in the long run.....however if your travelling through france and spain in august (by far the hottest month..trust me i should know, i used to live there) your engine would seriously overheat and you would be re-filling your coolant on a daily basis (probably)!!! and also your engine would under perform and may just give up before the trip ends....it can hit 40-45 degrees celcius on the outskirts of madrid in summer remember