I have 5-bolts pacers and Fuchs wheel son my car. I'm missing a few lug nuts, some studs came off when I removed them. Since I am planning on racing the car, do I or should I plan to replace the chrome "enclosed" lug nuts with "open" ones, so the scrutineers can see that they appear to be threaded onto the ends, or doesn't it matter? Either way, I need to buy a couple of studs for the empty in the spacers now that I have removed a security lug nut that was integral with the stud. Also, some but not all lug nuts had curved washers between them and the wheel, apparently to convert the lug nuts from a "vee" profile to a "domed" or curve shaped shoulder profile. Is it correct to assume that no matter what I choose to do about lug nuts, they must be domed, or made to appear as domed by using the washers

Since I know you all are going to ask for them, here are some pictures.

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IMO you have to use steel open lug nuts with the spherical seat (no washers) and switch to 5 lug hubs.
I don't think those adapters are safe for racing.

Those aren't proper 5-lug studs to begin with. The correct studs are pressed in and can't come off with the nuts.

And the nuts don't look right either. The correct closed lugnuts for those wheels look different.

Either way, if you plan on racing the car, you will need to take the wheels off and find out exactly what's going on.
My guess would be some sort of redrilled 4 hubs or 4 to 5 adapters, both of which won't be legal with most of the racing clubs.

And lastly, open end steel lugnuts are cheap (well, that is relative) insurance for you and the tech inspector.




Here are some pics of my car. 100mm studs front/rear, from this thread:

Took a couple of pictures of my hubs, as the wheels are off. Only four studs in place, as one had threaded out with the lug nut on each. What do you guys think?
Rear.Click to view attachment
Front: sorry it's a little fuzzy.
Click to view attachment

on Andy's points. In some sanctioning bodies you'll be required to use spherical steel lug nuts regardless, as long as you use studs. Look up your rules on both stud/nut use compared with four-bolt wheels. That'll tell you what you need to do.

I wasn't allowed to use my rear-wheel adapters when I first bought my car and had to convert to five-lug to run my first DE at Sears Point. It took Rich Bontempi a couple of days to do it since the PO had all the hard-to-find parts in the trunk of the car.

Good luck!

Bolt on 4 to 5 lug adapters. Over here, those are not legal for any of the major racing organizations.

Those screw in studs are very soft and will twist off pretty easy. I had some on my car when it was my DD and I twisted two off without much effort.

Is it possible to drill five holes into the hub that line up with the five bolt pattern on teh adapter and insert a shouldered hardened lug stud in from behind, threading each one through the threaded hole in the adapter? Wouldn't that be strong enough, or would the concern be the weakening of the hub itself due to the drilling of the five new holes. Until I take a closer look, I'm not sure if what I'm talking about even makes any sense. If I can't use the adapters, and I don't want to revert back to using the four bolt hubs, what are my options. I know this might be covered in earlier threads, which I will search this weekend as well.

Lug location is important enough that I would want the hubs drilled in a milling machine in the exact location for each hole.
I believe Eric Shea sells redrilled hubs which are properly reinforced on the back side to prevent weakening of the hub flange.
He may also be doing 5 lug conversion of front rotors now.

I would drill out the adapters to use as spacers after that.

It would be more cost effective to just switch back to some 4 lug wheels. Bolt on adapters are scary. There are numerous threads here on how to properly convert to a 5 bolt setup. The route I took was to find some early rear hubs with the stud bosses on the back and then use a mill to drill them flat. I redrilled my rear rotors but you could also just buy some 914/6 rear rotors. On the front I used the struts from a 72 or 73 911 complete with hubs and brakes. I'm using 100mm studs out back and 75mm ones up front. Open steel lug nuts all around.

Good eye Scotty. I'll be going through the entire brake system, and rebuilding all the calipers. Already have the rebuild kits for the rears sitting on the bench. Looking to do a proper 4 to 5 lug conversion with 911 stuff, so I might be changing calipers anyway.