wow, i didnt thing this tread was goin to be so exciting. hehehhe... for me i think its best to wait 5mins to before u check your engine oil.by the way i think that NAscar race cars have dry sum oil systems, so i think it would be different, from normal private cars.and i have also noticed that some cars have on the dipstick an add mark and a full mark. and like they say if ur oil level is between the 2 then your in the clear.anyways thanks for the insights. and ya i agree wit slip-slick, theres hardly a difference. whether the engine is cold or hot. because we liv in the tropics, where the weather is fairly the same temperature. in colder countries there might a significant difference.