thanks man im goin gto be running a 15x8 drag star wheel with a 275/40 tire. do you think i wil still need spacers? or should i go 15x10
I couldn't tell you. Don't know too much about upsizing of tires. ???
275mm tire is a bit wide for a 8" wide wheel. I've seen pics and heard of people doing this, but you will have sidewall bulge and if you take corners extremely fast the added stress in a weakened sidewall could flex and break the seal causing tire damage and loss of air pressure. 275's fit best on a 9" wheel.
Are you using this for daily driving? If so, to keep your speedo and odometer accurate, you need to go with higher profile tire, like 275/50/15. The size you mentioned above is 23.7" in diameter vs. the calibrated 25.7". That's about a 2" difference and your speedo will say your doing 75 when you're really doing 69.
Just something to think about.
You could go with 1" spacers using the 8" wheel - it really depends on the offset. I'm putting on 1" spacers after I install my C springs. In my opinion, you should drop your car before installing the spacers.