MR2 (00-05 spyder) stud specs- 0.559" knurl, 40mm length, m12-1.50

According to ARPs catalog, it looks like the IS300 studs will work perfectly with lancer and celica studs as a close 2nd. IS300 is 66mm under head length(26mm longer). In my experience with wheel studs, you can go about 5 or 6 thou over sized before the hub will crack from hoop stress, when made of cast iron(GM metric chassis shit I do). Im pretty certain these hubs are all steel, so you could add a few thou to that number I would think, and Im pretty certain the 0.565" knurl diameter of the lancer and celica will be just fine. You can also dril the hubs out to fit whatever stud you choose provided they are a larger knurl and not smaller for obvious reasons.




https://cimg0.ibsrv.net/gimg/www.mia...7740ea9ac1.png

Much excite. My current hubs have only about 10 hours on them including transit time, but the part of me that likes to completely overbuild things eagerly awaits these.

I also plan on making some when the budget allows, so probably mid/late March. Will be able to provide machining services for others most likely. Very stoked!

Y'all making me feel good for actually being interested in something I discovered and that actually contributes to the cause :D yay me
I should have the specs this week, with pics

I believe IS300 arp studs are 0.559-ish.

Edit: I missed Sean's latest post.

You should absolutely feel good, this is a fabulous thing to discover, Gene!

Heres what I got


This is Preliminary!!!!!!!!!!!!!!!

Edit- see post #108 for final drawing

https://cimg5.ibsrv.net/gimg/www.mia...a5c0b9600b.png

Some clarification on "bore C": This only needs to be opened up to fit the mazda axle nut which is around 1.8" OD on the flange, the ID of the hub bore is 1.765". A spacer/washer needs to be used under the nut since the splines stick out past the seating face, and so that the locking tab of the nut ends up where it should be. There is a really healthy chamfer at the bottom of the bore where the nut would seat, and since you have to make a washer anyway, you can either:
1. Make the washer OD small enough to fit inside the chamfer so it seats flat, which is 1.600" max. Then you only have to bore as deep as the nut flange sits, about 0.250"
or...
2. Bore all the way down to the face to whatever ID you desire granted its larger than ~1.820" but less than 1.965"ish, and make the washer whatever size you want to fit in that ID. It looks like genesplicer's machinist did the latter and maybe even press fit the washer into place, which I think is a great idea.

With this configuration the wheels will be pushed out 0.038", or just less than 1mm.

Also, the alternative wheel stud pattern on the mr2 hub is indeed 4x100, and the IDs are ~0.589".

Excellent, thanks!
I'll order a set today, been meaning to replace the hubs before SLB and ran out of time, at least I'll start this year fresh :)

I am pursuing making a batch of these as well, have a date with a machinist this afternoon. I haven't gotten final measurements yet, but it appears that there might be some slight differences in the mr-s hubs. Did you use the Toyota hubs or the ones from Autozone? I've got a Duralast mr-s hub from autozone. Also what are you doing for the big washer on the back side to space out the wheel bearing?

I meant to ask in the previous post why the large washer is needed to space the hub from the knuckle?

I honestly havnt had them in a knuckle yet so I may have posted prematurely. Thinking about it, the only issue I can see is the back of the studs rubbing something on the knuckle, or the seal lip seating too far up the radius... probably the latter looking at it now.

These are china from rockauto

https://cimg6.ibsrv.net/gimg/www.mia...bfef085dc8.png

I believe Genesplicer implied that the big washer is needed to space the hub face OUT about 1mm so that the brake disc is still centered in the brake caliper. I have some question if that is 100% necessary. I also don't see why you need a washer in bore C, that appears to need to be machined down regardless so why not just machine to the depth you need and leave out the washer?

Bore C washer is probably for engineering purposes and / or so you don't get binding with the nut.

Bore C washer is probably for engineering purposes and / or so you don't get binding with the nut. Even though it is a flanged nut.

OK I need to double check some things, maybe I didn't carry a 1 lol. I measured that the wheel was pushed out 1mm as described above, adding a spacer would just push it out more. I might have my directions wrong and that may be "in" and not "out" lol.

The washer is needed because the splines poke through, the issue is that bore C is too deep, not that its not deep enough. You have to add material.

Ok, now I'm seeing what Gene did, I couldn't figure out why he machined the splines in the hub out, but you are right he added a piece. And yeah by eyeball it appears to me that if you don't have a spacer on the wheel bearing side the wheel will be moved in 1ish mm.

Im curious, to know how much that really matters with a factory caliper or even a wilwood as there is a little bit of wiggle room. In either case that can easily be added if necessary.

I agree. Especially for a single piston/stock caliper, which should self center anyway. If it became problematic you could also just shim the caliper bracket out 1mm. Probably easier to buy off the shelf hardened washers for those bolts vs machining a custom one for the bearing.

I think most of the time that 1mm offset wouldn't cause any issues with bolting it all together and rolling down the road. I'm less sure what happens when you are on the ragged edge on track and if that would have any effect on brake wear.

Also I think for the guys that are trying to run maximum wheel and tire width that small change in the offset could mean they have to get a 1mm wider wheel spacer.

Just looked at my numbers and yea I was thinking backwards :loser: the hubs in my possession are indeed 1mm in and not out.

I would agree on spacing the caliper rather than the hub, being cheaper/easier/better, except that the caliper bracket mounts to the outboard side of the upright mounting tabs and that would space the assembly out rather than in.

Assuming there is sufficient travel available in the caliper sliders and pad abutments(where the pads slide in the caliper bracket as they wear), I cant see this causing any issue.

The MR2 hubs without the hub spacer would push the caliper off the pins 1mm(caliper would move left in the pic away from the bracket), and bring the rotor 1mm closer to the bracket
http://www.miata.net/garage/ebrake/FigureD.jpg

Im thinking something like this

https://cimg3.ibsrv.net/gimg/www.mia...5cde8d2e01.png

Edit- fixed pic