Forums/Z31P/z31-performance-upgrade-forums suspension-chassis-and-brakes/Real reason for 87-89T hubs?
Imported from Z31Performance.com Forums{{#if:RocklinMike300zx| — original post by RocklinMike300zx}}{{#if:2013-07-26 04:35:31|, posted 2013-07-26 04:35:31}}{{#if:21| · 21 post{{#ifeq:21|1||s}}}}{{#if:/Z31performance_archive/forum/z31-performance-upgrade-forums/suspension-chassis-and-brakes/22228-real-reason-for-87-89t-hubs.html|
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RocklinMike300zx: (2013-07-26 04:35:31)
So I've been trying to find the answer but for some reason (incompetence or lack of people asking) I can't seem to find a final answer. When doing a Z32/R32 (or 87-89T) brake swap, why exactly are the 87-89T hubs needed? I've seen people say bolt-on vs. slip on rotors, but why is that particularly significant? Is it just a need for longer studs or is there something physically preventing the larger brakes from being used on the older hubs that cannot be given a fairly simple fix? Just curious, because I am getting larger wheels and would like to have some better looking brakes to go with them, but if I absolutely have to get the late model turbo hubs then I'll be spending a pretty penny more than I planned on already.
I also figure I can't be the only person stupid enough to ask so it could be valuable for someone else that wants to see the same answer in the future.
Oh, and yes, I really just want to get bigger brakes for the looks. I don't want people seeing my puny ass brakes when I have wheels that actually expose the calipers and rotors.
adamvann3: (2013-07-26 05:01:19)
Most aftermarket rotors (specifically the rotor hat) do not fit over bolt on style hubs. People have turned them down to a smaller diameter in the past (though I am unsure the offset difference between the two) to make room.
Slip on (late turbo hubs) accept z32/s-chassis/r-chassis brakes or brake upgrades with just shimming the caliper (by shim I mean a washer).
G-E: (2013-07-26 05:29:52)
Sounds like you need a bbk for the non-turbo hubs and have them shaved down … much cheaper than buying the turbo hubs at current market price, savings that can then go to the rest of the upgrade right? [archived image: wink.png]
Go see the ASCO subforum for the groupbuy [archived image: smile.png]
Switchback Motions: (2013-07-26 14:05:00)
As adamvann said, people machine the bolt-on style hubs down to a 140mm diameter and press in Turbo wheel studs. After that it is just a case of spacing the caliper with a washer to achieve the offset required.
adamvann3: (2013-07-26 15:14:26)
Has it been confirmed that bolt on style hubs have the same offset as slip on hubs? I know people have shaved down the bolt on hubs, but it normally involved something other than the z32 rotor and brake setup.
G-E: (2013-07-26 15:33:34)
No the bolt on hubs without a rotor are the same height as the slip-on hubs WITH a rotor
Tempestas: (2013-07-26 16:14:21)
i have turbo hubs laying around that I will never use… what do they go for these days? I can't even find any for sale to see.
reddzx: (2013-07-26 16:35:51)
I have seen them go for as much as $250, but $150-$200 is more likely.
adamvann3: (2013-07-26 17:44:43)
Ok, I dug through the brake thread and yes it looks like a couple of people are running straight z32 setup on turned down bolt on hubs. I just never really saw any good confirmation (but james should be able to put this to bed). I just know when I switched from bolt bolt on hubs on my 86 (zenki style hubs) the rear dust boot/seal would interfere against the spindle/dust shield. I had to install bolt on style rear seals onto the slip on style hub to make it work.
This is why I was unsure of there was a difference in hub offset. I know slip on hubs only came with the twin piston calipers, so I was unsure if the caliper was offset accordingly.
RocklinMike300zx: (2013-07-26 17:50:27)
So it is possible to turn down the bolt on hubs, but considering the time and effort required it is just easier to go with the 87-89T hubs, yes? I found some R32 brakes at a good price and plan on getting them, so I guess I'll just figure out what to do about the hubs when the time comes. I just figured it would be good to get the options all laid out in one spot so I can figure it out a bit easier.
adamvann3: (2013-07-26 18:04:39)
Yes, 87-89t (slip on hubs) would be a bolt and go. Your bolt on hubs would need to be modified to work.
RocklinMike300zx: (2013-07-26 18:07:01)
Sounds good. I feel I should probably run to the junkyard and start ripping front hubs off all the late model turbos around here. Could make some decent cash that way it seems.
michaelp: (2013-07-26 18:09:12)
I don't understand why anyone would want a BBK that requires having the hubs turned anyways…when you can just have the hubs turned then run any of the Z32 BBKs like people have been doing for years. A true BBK for bolt-on hubs would be one that requires no modification to the hubs. IMO
adamvann3: (2013-07-26 18:10:06)
Alright, I was digging through james's build thread and tried to search out some post in the suspension area as I know he went into more depth on everything (why can't we search sub-forums?). Looks like he used r32 calipers and rotors.
I do remember him going into the bore size on the bolt on rotors IIRC it needed to be turned down as well (thats why he shows the measurement below). Again, when he reads this, I am sure he will chime in.
Switchback Motions: (2013-07-26 18:54:41)
I believe the center bore is turned down to fit a new spacer to keep the rotors hub centric as the bolt-on hubs have a smaller surface in this area. Bolt-on hubs have approx 5mm bore depth where slip-ons have approx 15mm bore depth.
G-E: (2013-07-26 19:33:02)
1. A bolt-on hub has a plain 66mm bore, the slip-on hub has a stepped bore 66mm and 68mm.... the rotor I.D. is 68.1mm, the wheel I.D. is 66.1mm
2. The bolt on rotor has a shorter hat as it mounts to the backside, but is also thinner, so the inner surface of the rotor is almost the same as the slip-on turbo rotor
3. If using a bolt-on hub lathed to allow slip-on rotors, there will be a 1mm gap around the bore between the hub and rotor, you can lathe the hub bore a bit and machine a spacer ring, much like many wheels are sold with a large 73.1mm bore and a spacer ring to reduce it for the application, which in most mid-80's and up nissans is 66.1mm
4. Lathing a bolt-on hub should not cost more than obtaining a slip-on hub, but your results may vary… a "fair" price for lathing the hubs is $40 each, use your judgement
5. There are currently 2 big brake kits designed for use with bolt-on hubs lathed down to ~150mm to accept the rotor as a slip on, using longer studs as well -- htey are designed to use the 66mm bore
6. Using a bolt-on hub with a slip-on rotor ultimately removes the 66mm bore from use by any corresponding wheel, bolting on a hub-centric spacer with a 66mm lip may sound like it fixes the problem for the wheel, but consider that there's nothing centering the spacer except the lugs anyway, so you can skip the hub-centricity and use the lugs to center your wheel directly
7. R32 GT-R rotors and calipers work perfectly on slip-on hubs, all you need is 4mm of washers between the caliper and mounting ears, and of course z32 conversion lines
michaelp: (2013-07-26 20:21:37)
Same process as Z32 brakes…likely because R32 and Z32 suspension and brake setups are nearly identical.
RocklinMike300zx: (2013-07-26 22:52:18)
Alright, well it seems I may be well served to find some late model turbo hubs, and as luck would have it there actually is an 88 z31 in a nearby pick n pull, though it is probably not a turbo…anyways, I'll be heading up there probably Monday and while I'm at it I think I will grab some J30 hubs, as I believe they are the same, no? At least, I think I read that in the brakes thread, and even if they aren't I can sell them to an s13 owner for use.
reddzx: (2013-07-26 23:27:53)
J30 are not the same
RocklinMike300zx: (2013-07-26 23:46:26)
Ah, that's a shame. Guess I'll snag them to sell to the 240 crowd but I'll have to either do some machining or hope the 88Z is a turbo at the yard to save some money on my hubs. I actually like the idea of fabricating my own stuff but I am also a lazy slob sometimes.
G-E: (2013-07-27 00:08:35)
For some stupid reason, nissan like other manufacturers switched to sealed bearing hubs in the 90's… so we share a spindle design with s12, r31, and the elusive m30, anything newer is nothing like