I know the hubs are an area of concern, specifically on 88-91 crx/civic. I have seen the "heat treated" hubs for sale for alot of $, but what is the actual process they are using to "treat" the hub?

 

You'd have to ask the manufacturers...

K

 

I assume you're referring to wheel bearing hubs?

If so, I can speak with some knowledge -- I used to work for the Delphi Automotive plant that produced some 90% of GM's wheel bearing assemblies.

The hubs and spindles, between which rotate the ball bearings, are case hardened to a Rockwell C hardness of around 60 via induction hardening and immediate quenching.

This is fairly standard surface treatment for bearing components.

 

http://www.sbmsinc.com/race_shop.html

These are what I was talking about specifically.....

Just wondering what the actual process is...

 

Yes, it appears those are the hubs that I was referring to.

I would be shocked if the OEM part was not heat-treated. Any bearing surface must be heat-treated to ensure durability and impact resistance. Untreated metal would be too soft for the contact pressures found in ball bearing races.

To what standard the OEM part is treated to vs. the aftermarket part, I have no idea. Perhaps the aftermarket part is through-hardened instead of case-hardened, meaning the entire thickness of the metal is hardened. This is not always good, however, since the softer interior metal of a case-hardened part will have better fatigue resistance than the harder, more brittle surface metal.

To answer the broader question of “what is heat treatment,” that is a very complicated answer. There are many types of heat treatment, each designed to accomplish a slightly different goal. But the basic premise of heat-treatment is to harden a metal and increase its ultimate strength by heating it, and then rapidly cooling it, thereby changing its crystalline microstructure in order to promote a certain characteristic.

 

Allen-

thanks for the reply. Maybe I will give the SBMS a call and see what they have to say...

I will keep you guys posted.

 

The bearing does not ride on the surface of the Honda hubs. The races press onto the hub. My understanding is that they break at the junction between the part the bearing race presses onto and the flanged area that the studs are mounted in. My suspision is that they anneal that area to make it less brittle.

 

Some of the guys get them cryo'ed...
that maybe ceaper.

 

Yeah I was thinking of a method that would yeild the same results, but basicly something I could try and get done on a local level and therefor cut cost.

 

Relatively local... and they race!

http://www.nwcryo.com/index.html

Greg

 

Sounds like changing the "rockwell hardness" is the process. Also shotpeening to relieve stress.

 

if this is the same stuff sold by OPM, and it looks like it is, then it seems the hub is actually a totally different hub that was machined from scratch using better steel. i bough em after breaking both hubs. cant say they have really performed any better since i didnt race much afterwards, but im sure they are better and worth it.

you MUST replace your old stock hubs and bearings BEFORE racing, and you might as well use these instead of buying stock.





Modified by Tyson at 3:02 AM 11/18/2003