FC Hub question
 

I have an 84 FB with a FC front crossmember/ suspension conversion. I am interested in changing the front bolt pattern to the 4x110 pattern.
My questions are:
1. Is there a steel hub that can be used on the stock FC spindle?
2. has anyone tried welding and redrilling a FC 4 bolt hub for different bolt patterns?
3. can the stock 4x110 FB hub be adapted to fit the FC spindle?
4. Any other ideas out there?

Thanks,
Dave

conversion
 

Not sure if the 4 bolt hub for the FC is the right pattern.
These should be easy to find since everyone wants the 5 lug.

The 4 bolt for the FC is a 4X114.5 pattern.
Dave

Off the top of my head, the inner wheel bearing on the FC hub has a larger inside diameter, so the spindle would have to be machined down to accept the FB hubs, or the hubs would have to be machined to accept the FC bearing races. The FB has those nasty integrated brake rotors on the hubs too, which... well, I wouldn't pick them willingly given how many we've cracked on the ITA car.

Steel hubs I don't know where you'd buy to fit the proper bearing race sizes; there's various stock car ones out there, but they're the wrong bolt pattern and bearing sizes. You could turn some on a lathe from billet, but that really seems like more trouble than it's worth. Welding and drilling the stock FC hubs is an option I suppose though I don't recall offhand where they have the material. And either way, you'd have to machine new bolt holes in any new brake rotors you got.

In essence, I have to question why you're looking at going to 4x110; why not redrill the rear axles to 4x4.5"?

The reason I am sticking with the 4x110 bolt pattern has to do with the 16 15X6 Team dynamics wheels that I have for the car.

Figured it might be something like that. Went and checked the FC hubs we have sitting around, and aside from filling the bolt holes up with weld and drilling new holes, modifying them isn't going to work so well. So it seems to me you're looking at the POS 12A rotor/hubs with modified spindles (which, well, when I started tinkering with the FC subframe swap, part of it was to get bigger brakes, so...) or making new hubs out of billet and redrilling brake rotors. Which of those you pick is probably going to depend on why you're doing the subframe swap in the first place.

Actually, another thought is the 7s Only brake kit; they sell a billet hub with everything else, and you could turn the inner bearing carrier to fit the FC bearing races. http://www.sevensonly.com/ is the site. Kinda pricey, though I look at things from the perspective of a broke-ass college student and prefer to fabricate things... ;)

dont buy new stuff.. also dont weld in the old bolt holes.. have a machinist in your area weld in the two small holes that are 45degrees off from the studs.. of course remove the studs first. then have him redrill holes that are 4x110 45 degrees off from the original holes.. that way if you ever want to switch back you still have the option, (for an -se rearend or w/e) the hubs will be strong enough to redrill,, also make sure to have the rotors redrilled.. i wouldnt weld those ones iether, because again you have interchangeability and with welding you run the risk of warping the rotors

i plan to have my se rearend redrilled to 5x114.3 so i can use t2 brakes. and run 5lug hubs up front also with t2 brakes (have the fc subframe swap) .. and i am confident that they will be more than strong enough to have a redrill..

good luck with the project

Paul

The problem is, at least on the 4-bolt FC hubs I have sitting around, 45 degrees off the studs is a big empty area where Mazda saved weight.

ya i just went out and took a look aswell, i thought that was only on the rear, sorry
i guess you would have to have them welded in, or you could try and put them 22.5degrees,, draw it out and see if theres at least 3/8" of steel that you could use, (from the edge of the "big empty area", i would rather see 1/2 all the way around the stud. but i think 3/8 would cut it,,

its worth a try at least for the exta bolt pattern option.

Paul

bolt pattern for 4 lug FC is 4x114.3 NOT114.5!

^^^^^ everyone gets that wrong!!, its funny.

I am going to try measuring the inner diameter of both the inner and outer bearing and then head up to the local junk yard to see if I can find any steal hubs that will fit. I am concerned that welding the hubs will weaken them. (I forgot to mention these are for a rally car.)
http://www.performancerallyimages.com/tp05-24.jpg