Can you please provide some engineering data to back up your recommendation of "10mm spacers max" ??

You can't just throw out a random number without backing it up with either hard data or first hand experience. . .

There are a plethora of folks who use 25mm or larger spacers in racing applications all the time with no problems. And racing on slicks will put MUCH more force to the wheel and hub than a daily driver on street tires. . .

EVOlutionary

 

I'm with him^^
No idea where you heard that silly info.

 

Are they running 25mm + spacers with extended studs or just the spacer? Wanted to push my stock BBS rims out towards fender ( can't afford rims with all the parts I need/want). Was considering H&R spacers with extended studs and hub centric. Anyone else doing this? Would like to see pics and spacer size. Was thinking 15mm, but haven't tested with washers yet to see what size would look best.

 

Extended studs, absolutely. On my EVO 9, even with only a 5mm spacer I needed longer studs to get enough thread engagement to be safe.

 

I am using 25mm custom hubcentric T6061 spacers in front with the ARP extended studs. I am able to get more than 10 full turns on the studs so I reckon they are tight enough. However, I'm still not sure if I can trust this setup to hold up under real racing with 265/35R18 slick tires

 

As long as your wheel spacers are hubcentric, they will not impart any abnormal load to either your hubs, wheels, or studs.

I run a similar setup - 15mm hubcentric spacers, 285/30/18 Hoosier A6 tires, ARP studs, Kics lug nuts. Been using the same lug nuts for 3 years, and the same wheel studs for 2 full years of autocrossing. We see up to 1.45 G's lat accel. . . and never had a single issue. . .

(one other thing to consider is that CCW, a top American racing wheel manufacturer, ships many of their wheels WITH spacers)

 

That's reassuring to know