Cut Down Rotors as Hubs?

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TJ530
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Cut Down Rotors as Hubs?

Post by TJ530 » Wed Oct 18, 2017 8:32 am

Hello after doing quite a bit of pricing for the various disk brake kits on the market I’ve found most are rightfully expensive and few are in the more common wheel bolt patterns(4x100, 5x114, 5x100). Because of this I’m looking to make my own using wilwood components and cut down stock rotors(redrilled for 4x100) as hubs for the rotor hats to slide over. I know this has been done a few times by various people(Pile, Gerrelt(sp)) and wanted some feedback on the techniques used to cut the rotor down and if there’s any concerns with doing so what those concerns are.
Thanks!
TJ

H2OSB
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Re: Cut Down Rotors as Hubs?

Post by H2OSB » Wed Oct 18, 2017 10:17 am

I'd like to hear info about this as well. I've recently been looking at the hubs created by Latest Rage for ball joint front ends. After talking to the guy at LR who created the hubs, he recommended NOT redrilling them (I'm going for 5x130 pcd).

Another hub I've looked at I THINK would work fine is the new-ish hub/rotor set up created by CB Performance. I also believe you can get THOSE in 4x100 pcd. They sell as replacements for $164 each with isn't bad for custom hubs.

Fortunately for me, I'm only concerned about the front. I will use 944 brakes for the rear.


H2OSB

TJ530
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Re: Cut Down Rotors as Hubs?

Post by TJ530 » Wed Oct 18, 2017 11:08 am

As I’m trying to redrill for 4x100 that may work out better since it can be offset 90 degrees and not end up with two holes very close together.
I’ve asked CB before if you can get those hubs blank and was told no. They will sell them separate from the rest of it if I remember correctly. For the rear that makes it easy to get a hub.
I’ve additionally thought of using the LR balljoint front hub for a sandrail as my hub, redrilled of course, and cut down and redrilled type 3 rear brake hubs for the rear. It would be easier to just use the stock rotors as I have a set and Topline is close by.
Last edited by TJ530 on Wed Oct 18, 2017 11:32 am, edited 1 time in total.

TJ530
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Re: Cut Down Rotors as Hubs?

Post by TJ530 » Wed Oct 18, 2017 11:13 am

The overall goal for me is to get Disc Brakes with ventilated Rotors with easy to source parts in a common wheel bolt pattern.
I’m shooting for 4x100 since enkei makes RPF1s in a 16x8 et35ish that is extremely light. Since the super is gonna be used as a autocross car along with a daily driver it’s gonna need some good brakes and sticky tires.

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dlamyle
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Re: Cut Down Rotors as Hubs?

Post by dlamyle » Wed Oct 18, 2017 12:19 pm

I just did this to the fronts for some 5x100's and Subaru brakes. Turned them on a lathe myself and took my time setting up to get all the run out adjusted out. My local machine shop wouldn't touch the project so I had to buy my own Harbor Freight lathe.
viewtopic.php?f=8&t=150097
1968 Karmann Ghia , 'JDM EJ205, 5spd Subarugears w/OBX LSD, Blouch 16g XTR, Killer B Headers, DW 750cc, Meth Inj, Cobb AP w/Mach V 22psi Dyno tune (332whp)
http://www.shoptalkforums.com/viewtopic.php?t=143547
https://www.youtube.com/user/dlamyle1/videos

TJ530
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Re: Cut Down Rotors as Hubs?

Post by TJ530 » Wed Oct 18, 2017 3:48 pm

That’s what I’m talking about.
What rotors did you use as your base before turning them down?

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dlamyle
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Re: Cut Down Rotors as Hubs?

Post by dlamyle » Wed Oct 18, 2017 5:08 pm

TJ530 wrote:
Wed Oct 18, 2017 3:48 pm
What rotors did you use as your base before turning them down? c26-407-076-113 Looks like cip1 no longer sells the exact rotors anymore but this cross drilled version is close. c26-407-076-113d if you look at the photo of the back you can see it is solid. That's important for doing the 5x bolt patterns. There is a lot of meat on them.http://www2.cip1.com/ProductDetails.asp ... 076%2D113D
1968 Karmann Ghia , 'JDM EJ205, 5spd Subarugears w/OBX LSD, Blouch 16g XTR, Killer B Headers, DW 750cc, Meth Inj, Cobb AP w/Mach V 22psi Dyno tune (332whp)
http://www.shoptalkforums.com/viewtopic.php?t=143547
https://www.youtube.com/user/dlamyle1/videos

TJ530
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Re: Cut Down Rotors as Hubs?

Post by TJ530 » Wed Oct 18, 2017 5:36 pm

So those rotors have a thicker face to them than the ones with reinforcing ribs?
Ive currently got a set of 4 lug rotors with the ribs on them but obviously safety is key for brakes and the things holding the wheels on.

Lanner
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Re: Cut Down Rotors as Hubs?

Post by Lanner » Wed Oct 18, 2017 8:54 pm

Ive done it lots, for all kinds of setups. Stock rotors (actual OEM vw is best, high carbon steel) work well for 4-100, machine the pattern without offset from stock pattern right in the thick part and tap for m12. Id plug the m14 holes with threaded piece and red locktite. Or offset 22.5* from stock, spotface and press stud.

The LR stuff works well too, and the face is nice and thick for threaded holes. Depending on the OD you cut down to, I'd recommend threaded holes over press studs as the material is cast and can crack when you press the studs.

Ofcourse LR says not to do it, they have to CYA.

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DORIGTT
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Re: Cut Down Rotors as Hubs?

Post by DORIGTT » Thu Oct 19, 2017 3:46 am

LR stuff?

H2OSB
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Re: Cut Down Rotors as Hubs?

Post by H2OSB » Thu Oct 19, 2017 4:33 am

DORIGTT wrote:
Thu Oct 19, 2017 3:46 am
LR stuff?
Latest Rage

TJ530
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Re: Cut Down Rotors as Hubs?

Post by TJ530 » Thu Oct 19, 2017 1:52 pm

So the general consensus is that cutting down the stock rotors to be used as hubs can be done and is perfectly acceptable.
Guess I’ll have to save some money to have topline redrill my Rotors or what have people used to drill out the hole pattern?
So press in studs or thread in studs?

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dlamyle
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Re: Cut Down Rotors as Hubs?

Post by dlamyle » Fri Oct 20, 2017 11:51 am

TJ530 wrote:
Thu Oct 19, 2017 1:52 pm
So the general consensus is that cutting down the stock rotors to be used as hubs can be done and is perfectly acceptable.
Guess I’ll have to save some money to have topline redrill my Rotors or what have people used to drill out the hole pattern?
So press in studs or thread in studs?
I'd opt for having a machine shop do the bolt holes if that is an option for you. I drilled my own on a drill press using a wheel adapter that when bolted to the rotor in the 5x4.75 holes, located the 5x100 pattern for me perfectly. I was able to drill right through the existing holes to my modified hub with a fair amount of accuracy. I'm going to turn some hub centric rings with a built in hub cap to make sure my wheels are running true. My 14mm bit was the right size for the knurl I was using with Subaru studs. They pressed in with just the right amount of effort. My cut down cast hubs are very thick with plenty of meat on the outer edge so I couldn't imagine them cracking. Threads are a safe option for most applications but for track use I wouldn't feel too comfortable with cast threads and repeated usage. If my knurls spin or strip at least the stud stays attached to the wheel. It's a wash if you're talking about the type that screw in from behind.
1968 Karmann Ghia , 'JDM EJ205, 5spd Subarugears w/OBX LSD, Blouch 16g XTR, Killer B Headers, DW 750cc, Meth Inj, Cobb AP w/Mach V 22psi Dyno tune (332whp)
http://www.shoptalkforums.com/viewtopic.php?t=143547
https://www.youtube.com/user/dlamyle1/videos

H2OSB
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Re: Cut Down Rotors as Hubs?

Post by H2OSB » Fri Oct 20, 2017 4:24 pm

I, myself, have looked at and considered so many methods to do this. I had originally planned to just run n/a 944 spindles on my 1303, but nothing could get me past the camber issue without far more serious mods that I was willing to do. I would happy if I could find a pair of 1303S spindles...for a reasonable amount.

For the time being, I will be using early 914 rotors, re-drilled to 5x130 pcd, and have Lanner make me some caliper adapters for my Porsche M calipers. I have no issue using screw in studs. I perminantly lock-tite them in. I would prefer press in studs and may go that route as I'm already having the rotors drilled.

Regarding the CB hubs. I had been of the mind to use those with the older style rotors that bolt to the back of the hub, by redrilling the rotors to the hubs pattern, however I wasn't sure it would work. This seemed to natural method to use since that's how CB designed them, however I was looking at a pic of one of them the other day and it dawned on me they would work as an inside hub using the later '87-'89 944 rotors if a little material was removed from the outer edge. Hell, they even come with press in studs and 5x130 pcd. Not sure what i would do if going for a different bolt pattern

H2OSB

TJ530
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Re: Cut Down Rotors as Hubs?

Post by TJ530 » Fri Oct 20, 2017 9:40 pm

H2OSB wrote:
Fri Oct 20, 2017 4:24 pm
I, myself, have looked at and considered so many methods to do this. I had originally planned to just run n/a 944 spindles on my 1303, but nothing could get me past the camber issue without far more serious mods that I was willing to do. I would happy if I could find a pair of 1303S spindles...for a reasonable amount.

For the time being, I will be using early 914 rotors, re-drilled to 5x130 pcd, and have Lanner make me some caliper adapters for my Porsche M calipers. I have no issue using screw in studs. I perminantly lock-tite them in. I would prefer press in studs and may go that route as I'm already having the rotors drilled.

Regarding the CB hubs. I had been of the mind to use those with the older style rotors that bolt to the back of the hub, by redrilling the rotors to the hubs pattern, however I wasn't sure it would work. This seemed to natural method to use since that's how CB designed them, however I was looking at a pic of one of them the other day and it dawned on me they would work as an inside hub using the later '87-'89 944 rotors if a little material was removed from the outer edge. Hell, they even come with press in studs and 5x130 pcd. Not sure what i would do if going for a different bolt pattern

H2OSB
A buddy and I have been thinking about this a lot too. If this were a race only car I might make my own spindles and rear trailing arms and retrofit some bolt on hubs like most modern cars. I just don’t have the equipment necessary to stress test that idea to where I would be comfortable driving it on the street.
Who knows I may just decide to overkill them and make my own spindles and trailing arms. The Baja guys do it so why not me?

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