I've been searching around quite a bit, and I've read many conflicting opinions on various FC forums and around the web. I have a 16x8 Rim w/ a +38offset, its extremely close to the front suspension. I want to run a 10mm spacer. Is it safe to run a non-hubcentric spacer on all four corners? If not, where can I find a 10mm hubcentric spacer?

 

I ran some 5/16" non-hubcentric spacers on my front wheels when I used 300zx wheels for a while. I had a paper thin clearance between the tire and the spring, and a tad more than that between the tire and the fender when the suspension was compressed. I got these spacers on ebay for like ten bux.

I experienced no vibration, funny wobbling of the wheel, rough ride, or any problems whatsoever with the spacers. They were a kind of loose fit over the wheel studs and I lightly snugged my lugs on the wheel, then used my hand through its spokes to center the spacer between the wheel and the rotor boss, using eyesight only as a guide for center. And this method worked out fine for me, I had no trouble with the wheels and I put them through some ~1g lateral corners during street driving and an autocross that I went to.

88IntegraLS sez: non hubcentric spacers worked for me and gave no trouble when using 300zx wheels on my FC NA.