a drive trip is nice... very nice indeed.
what i wanna advise, is that u guys join a convoy or go in a bigger group. sore has many motoring groups n forums, there's frequent drive trips with proper planning, organization and the best things is - safety + discounted stays...
to be honest, of all the places... johor should not be a drive-trip. it's not as easy to get around unless u know your way well, and generally - saftey is a major concern. if just u guys, then consider malacca which is abt 2.5hrs drive. else join the groupies for drive to sebana, desaru etc if u want a short one.
do a proper research even though it's very near. better if u can contact your johor-frens who might be able to lead u over the weekends...
have fun.