They don't spell out c-clip eliminators, but is that what this means? Disk brakes work as an axle retention device as well.

I checked out a few of the rules from some local tracks and all that they mention is is "aftermarket axles required for cars faster than x.xx". Do I need c-clip eliminators? If so, at what speed?

Thanks, Austin

 

C clip eliminators are axle retention devies. They're required on cars faster than 10.99 or anything with a spool.

 

An axle retention device is designed to keep the axle from coming out if the c-clip retainer breaks off. C-clip eliminators are similar in design as Ford 9", Dana 44, Dodge 8-3/4" type diffs where the axle has a bearing pressed onto the end and held on with a flange.

A disk brake setup will also keep the axle from falling out so disk brakes also qualify as an axle retention device.

If you break an axle between the wheel hub flange and the bearing, there's nothing that will keep the wheel on but that's not the purpose of axle retention devices since that's not the weak link.

Axle retention device and aftermarket axles are manditory on all vehicles running 10.99 or quicker in the 1/4 or any vehicle with a locked (spool) differential.

 

Disk brakes qualify as an axle retention device... that is exactly what I was looking for. Thank you

 

I would personally vote against c-clip eliminators, especially if you drive the car on the street, and/or also autocross it. Every c-clip elimiantor I've seen leaks within a year. They also use fairly small bearings, which don't tolerate side loading very well, and in cornering applications can fail. If you're serious you need to upgrade to a better rear that has positive axel retention like a Ford 9" or aftermarket 12-bolt like the ones you can buy from Moser that are designed without c-clips. Another options would be to have the ends of your axel tubes swapped for 9" style ends and have custom axels made to work with the setup. The cost of this is probably prohibitive on a 7.625" 10-bolt, because all you'll have is a great set of axels in a rear that will probably fail for another reason, and the money would be better spent just upgrading the entire assembly to a better unit.

BTW, I would check to see if disc brakes qualify as an axel retention device. If the axel snaps at the junction of the flange and the bearing, which is a common occurance on older rears, the wheel is going to walk right off the car taking the disc with it. The caliper bracket and caliper may hold it for a few hundreths of a second, but considering the power involved the wheel could still come off, or at least make a mess (which is what the rulebook is trying to avoid along with the potential for bystander injuries). I would talk to someone on the IHRA website and see what's legit. There's nothing more frustrating than going to the track and getting booted out after your car fials tech, or you make a couple of quick passes that make them scrutinize your car closely enough to find fault.

 

The same thing will happen with a C-clip eliminator and the caliper will hold it longer. As I already mentioned. Nothing can prevent you from losing a wheel if that happens and that's not the purpose of an axle retention device.

Axle retention is to prevent the axle from coming out in case the C-clip retainer breaks which is a common occurance. Technically Ford 8/9", Dana, Dodge 8-3/4" don't qualify for needing an axle retention device because they don't use c-clips to hold the axles in.

Less common is if an axle actually breaks inside the tube. The c-clip will hold the inner part in but the rest of the axle/wheel can exit the vehicle. As long as something on the outside such as a disk brake, c-clip eliminator, factory bolt on axle style is used, even a broken axle on the inside will stay in place.

 

I go to a road course a few times a year so I definitly want wheel bearings that can handle the turns and be IHRA legal. Moser offers hobby stock housing ends Moser Engineering that are supposed to be made for road race cars. That is more expensive and complex that just buying aftermarket axle shafts and using a conventional c-clip with disk brakes. I was considering them but since disk brakes are considered retention devices I don't need them.

 

Are we sure that the IHRA qualifies disc brakes as an axel retention device? I'm not saying they don't, but I want you to be sure that they do. Interpreting the rules, or going by logic or something you heard won't cut it. The only thing that matters is the IHRA's position on disc brakes as an axel retention device. It seems like Stephen 87 IROC races quite a bit judging by his car, so I'm not disputing his claim just to be argumentative, I'd just like to get to the bottom of this issue and make sure that the information presented in this thread is 100% legit.

BTW, I've had c-clip axels break before and not come out of the tube. Usually they don't walk out until you try and turn the vehicle. Another common occurance, in fact I think more common than a broken axel, is a broken side gear in the differential. This is especially common on rears with over 100,000 miles on them. The side gear can break and allow the axel to exit the rear, and you're confounded because the end of the shaft isn't broken yet it's lying on the ground with the wheel and brake drum still attached.