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Small vs large bearing spindle and hub-rotor choice

Old 06-14-12, 08:45 PM
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Small vs large bearing spindle and hub-rotor choice

I have an 83' ITA RX-7. What type of spindles do most of you guy run? I know Brembo makes a hub/rotor for the large bearing spindle. I have small bearing spindles and I'm putting on "Power-Slot" hub-rotors from Tire Rack. They're rated autox/track. Anybody try these yet? I have a pair of large bearing spindles I may switch to this winter so I can use the Brembos.
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Old 06-16-12, 06:46 AM
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While replacing my hub/rotors I removed the outer race and found a machined spacer in between the race and it's seat. About a 1/4" machined spacer. Anybody ever see that? I can't find it on any parts list
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Old 07-11-12, 01:07 PM
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The bigger nearing spindles are supposed to be stronger. Should be since there's more material there to take the stress and heat. Those races come with the replacement bearings. Not sold separately.
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Old 07-11-12, 04:05 PM
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Before spending big bucks on rotors, consider this:

4 or 5 years ago, I replaced all for rotors on my daily driver/autocrosser. I bought the cheapest rotors available at Rockauto.com and added Hawk HP pads. Performance is great, and I haven't had a single issue.

Just a thought.



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Old 07-11-12, 05:17 PM
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On something seeing road courses for a 1st gen that's nooooot a good idea. OP is in Wisconsin, which includes Road America. The 1st gen rotors are known to sometimes crack, especially under roadracing punishment with sticky tires and tiny stock size rotors, as required in Improved Touring. This crack can migrate to the portion that holds the bearing, which can cause the wheel to fall off. Now imagine this happening around the kink at around a hundred miles per hour. It's why EProd lets the 1st gens have an aftermarket, separate hub and rotor.

Big bearing spindles just have better availability of parts. It's worth your while to swap over sooner or later.
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Old 07-12-12, 12:14 AM
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blank rotors are best for track. well, best for everythng except car shows lol. all that slot/hole crap is just marketing (unless you have asbestos pads...)

Napa rotors seem to have a good rep, and of course Brembo does. Either way, if a rotor is $20 you wont cry when it cracks. Run good ducting if you want your brakes to work on track, autox doesnt matter.

And if you are planning to race, definately go with larger bearings. bearings wear fast on track.
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Old 07-12-12, 01:00 PM
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Thanks for the replies. Switched to the large strut/bearing w/ Brembo's. Struts are the next issue. I'm going to install 2" strut tubes in the spindle body to accommodate 8610 koni's. I've found it difficult finding tokico adjustables. All on back order. Mustanghammer gave me the idea. Will try and do it before Road America in August.
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Old 07-12-12, 01:55 PM
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the big spindle is a good upgrade, but you still need to inspect the rotor and bearings after each event. you're looking for cracks in the hub.
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Old 07-12-12, 05:06 PM
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Originally Posted by Kenku View Post
On something seeing road courses for a 1st gen that's nooooot a good idea. OP is in Wisconsin, which includes Road America. The 1st gen rotors are known to sometimes crack, especially under roadracing punishment with sticky tires and tiny stock size rotors, as required in Improved Touring. This crack can migrate to the portion that holds the bearing, which can cause the wheel to fall off. Now imagine this happening around the kink at around a hundred miles per hour. It's why EProd lets the 1st gens have an aftermarket, separate hub and rotor.

Big bearing spindles just have better availability of parts. It's worth your while to swap over sooner or later.
Hmm, could be a good point, so I will defer to your experience. Although, I have taken the car to DGRR twice, and know for a fact that the rotors got a hell of a workout on the Midnight runs up and down the mountain. She's also seen a few hotlaps at Road Atlanta.

Also, I forgot to mention that when the rotors showed up, they did have the Brembo name on them (although I believe there are many counterfeits out there).

I definitely agree that slots/drilled rotors are for show. Very old brake pads suffered from a type of gas buildup between the pads/rotors, which led to the developement of slots and holes, but they are not necessary for any modern (post '90s) brake pad which to not "out-gas" like the old stuff.

Good luck, and have fun.
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