I've got a wheel problem

[augcam]

I need some help, I recently got some new rims,they are 18x8 with +45 degree offset. I pulled one of the fronts off and test fitted one of my rims. It was a tight fit!! There is only about 14/16 of an inch. I'm planning on running a 40 series. I know that some low pro's dont extend past the outter edge of the rim. Are all 40's this way or does it go by manufacturer or size? Or is it the width of the tire related to the width of the rim? I need to know so I can get the proper spacers if needed. The only hub-centric spacers I've found are H&R's and they aint cheap!!! Any help would be cool

[augcam]

maybe i should refrase my question, what is the widest size tire i can fit on an 18" rim and have it not stick out past the edge of the rim? also i test fitted the back wheel and it sits flush on the hub but it touches the strut. do yall think a 5mm spacer would be enough or should i go wit a 10 or 15mm? someone help please!!

[Nick]

8 inches = 203.2 millimeters, so 195's wouldn't stick out past the rim, 205's might be ok

play around with this to get the right width and sidewall

http://www.miata.net/garage/tirecalc.html