How wide?

OK I have a 91 240sx and I wanna get some 5Zigen FN01R-C's. I want to get 18's so I was wondering how wide can I go without rolling my fenders and how wide can I go with rolling my fenders?

with 18's it depends on the offset of the wheels. or you rolling your fenders will only get you maybe another 1/2 inch...but it all depends on the offset like i said...you can go around 9 front and 9.5 to 10 rear...measure from your hub to the inside of the fender. should be around 3 1/2 - 4 inches. then you just get the offset you want...which since you do have 4 lug it'll be hard to get the offset you want...but im sure you can def get something to fill stock fenders...if you go on zilvia.net they have a fitment page for offsets and wheels and that'll give you a good idea of what your wanting...lots of people have the FN01R-c's over there...

17x9 +15 Front 235/40
18x9.5 +12 Rear 235/40

That needs a decent pull in the Front And Rear. and A bunch of hammering as listed in my other thread.

18s on the front of a S13 with any decent size wont make it to full lock without tubbing.

PS. You didnt mention you had 5H? if you dont have it the best sized FNs you can get without going custom is 17x9 +20.

which the +20 FN will fit your car just fine...that will be flush

so it has to be 17x9 +20 all the way around? Is there anyway i can get a 18 in back without customizing that will be flush?

SPL custom 17x9 +20 in 4x114 bolt pattern for 240SX. Note: S13 chassis will require fender rolling. Is this true? I got this info from SPL Parts.

yes it is true due to the offset, but rolling your fenders is very very easy...i would recomend getting the 17x9 +20 ...some bad ass wheels