ok, trying to mount our new titan forged 20 inch wheels. These need 60 degree conical mounting lug bolts. Got a great deal on some titanium lugs through Katech. However I’m not real comfortable with the thread engagement. Always thought needed at least half of diameter of stud extending through nut. These are providing about half of the nuts threads actually engaging the stud. I need to extend studs at least 15+ mm. Found two part numbers for arp extra length studs, one for Corolla fronts (100-7718) and one for Lexus is300 (100-7715). These appear to give me the extra length I’m looking for. Will the is studs fit the RCF? If not, what are my options? What is stock length on RCF studs? I measured exposed stud length from rotor face of one inch (26 mm), but I can’t measure the entire length or knurled length without removing from rotor.
thank you in advance for any input!
BTW, 265/35/20 sport cup two’s will not fit on the front, but 305/35/20 will on the rear!!!
pix will follow once I have the sizing on front figured out

Thank you for your response.
I’ve ordered the arp studs, got them today and hope to have them installed this weekend in time to embarrass some Porsche’s at their autocross event next weekend.
Should be able to post some pix once done.

I also looked into titanium studs. I would agree probably not a good choice. ARP makes the strongest and (IMO) most reputable studs in the business. I ordered the IS part number and they’re good to go. Holding off on installing all due to being accepted for the PCA autocross event and needing to be teched on tues. not sure I’ll have the new tires (245/35) installed on rims by then so I’m going to run stock wheels that weekend.
There is an affordable and usable titanium nut though. Found them at Katech for a very reasonable price. Only weigh 16 grams each and have taken torque several times in test fits and drives.
FYI, PCA requires steel lugnuts on time trial cars but not autocross.

FWIW I’ve ran Ti lugs, not studs, on my track rims for about a year now. I have noticed they “come loose” ie out of torque spec sooner than steel or some alloy lug.
My Ti lugs are from Mackin. Assume it’s a good quality product.

Ryan, got a link to the Ti studs?
May give it a go if prices aren’t stupid...