Will a 5mm hubcentric spacer require me to replace the factory studs? Thinking I might need just that little extra for my planned autox tires to clear the front suspension upright.

Don't hold me to this, but I believe per z1 you don't need replacement studs for just a 5mm spacer. Aftermarket wheels you would. For the price of the stud and easy install though I'd still recommend it. Especially if you plan to ax .

just some more info

this is what I got for measurements on my nismo z:

oem nismo wheel studs

•rear studs 42mm
(25mm sticks out of hub)
•front studs 45mm
( 28mm sticks out of hub)
•hub takes up 17mm

studs from H&R 15mm DRM spacer kit


•h&r studs are 60mm
(because h&r dose not make 55mm studs just for 15mm spacers)
•Hub is 17mm
•spacer is 15mm
•leaving 28mm sticking out of spacer for rim and lug nut

so basically I can't run my oem wheels without my 15 mm spacer installed unless I cut my oem lug nuts to have open end nuts
(going to buy the z1 oem style Stainless Steel nuts to do this to)

So I don't need extended studs to install bolt on 20mm spacers ?

All about wheel studs and nuts
 

yes you will need new extended studs

^^^^
edit: sorry that's wrong info I'm retarded and read that incorrectly

u would be good to go with oem

No you dont, bolt on 20mm go perfect on OEM studs.

sorry he's right,
my apologies I miss understood that completely.
somehow I though u were asking about putting 20mm spacers on oem studs...

I'm looking to get 25mm hub centric H&R spacers for the rear. I want to use extended studs rather than built it ones on the spacers. What size bolts will I need and where might I be able to get them?

Someone please correct me if I'm wrong... the following ARP studs are 12x1.25 and just under 50mm in length. If I was looking to replace my OEM studs would these be a strong alternative for track days?

https://www.summitracing.com/parts/a...7728/overview/

I'm also thinking of using a 10mm spacer in the rear with my track day rims (OEM rear rays, square setup), but want to be able to use my aftermarket rims as well without having to switch to open ended lugs. If I threw these studs on all 4 corners would that make sense? Thanks for your input...