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roverman
Art Gertz
Winchester, CA.
(2977 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Full Floating Axles in road racing
Posted by: roverman
Date: November 20, 2010 11:36AM

Perhaps their required in some classes ? Anyone running these ? With 1-2deg. negative camber ? Reportedly, this is possible with off-set bearings,(no binding). Most quick change rear ends, have full floating axles,(safer). Discussion ? roverman.


Phillip G
Phillip Leonard
Kansas City
(395 posts)

Registered:
02/03/2008 04:12PM

Main British Car:
1992 MG RV8 Rover 3.5

Re: Full Floating Axles in road racing
Posted by: Phillip G
Date: November 23, 2010 09:53AM

Art,

good question.

I don't know. I will look into it.

keep them on the track,

phillip g


Bill Young
Bill Young
Kansas City, MO
(1337 posts)

Registered:
10/23/2007 09:23AM

Main British Car:
'73 MG Midget V6 , '59 MGA I6 2.8 GM, 4.0 Jeep

authors avatar
Re: Full Floating Axles in road racing
Posted by: Bill Young
Date: November 23, 2010 12:44PM

Art, I'm just a "hanger on" around the real racers but from the various British cars racing that I've looked at full floaters are not common. I believe that most of the top runners do use some camber in the housing, the amount is limited by SCCA rules according to the class, but as you say usually between 1 and 2 degrees, nothing more. According to one racer I asked about this that's about all you can run without haveing to run special "ball end" axles like the NASCAR guys do. I think the main reason that full floating axles aren't in more use is that many classes require the use of the original housing, so as in the case of most MGBs the racers use a modified housing with a banjo style inner section and tube type outer ends. This gives the better bearings of the tube type axle with the easy gear swaps of the banjo type and still the MG axle. That's interesting as the early banjo style axle is a full floating type and the later tube type axle isn't. The stock Midget axles are also full floating designs.
I was thinking about the rear axle camber issue and came up with this, if you don't take pinion angle into consideration when you set up the axle then you potentially could wind up with some toe in or toe out in the rear which might even be helpful for the handling of some cars. A lot of engineering to consider there.
As for the full floating axles being safer, I suppose they are. Especially when compared to a GM type axle which relies on C clips in the differential to retain the axles. If you break an axle then it can slide right out of the housing unless you have modified it with a retaining device of some type. In most cases rear disc brakes will keep the axle in place. It's very unusual to shear an axle outside of the outer bearing, so for Ford type axles where the bearing is pressed on the half shaft even breaking an axle inside the bearing area it won't slide out. I haven't checked, but I'd bet that stock cars using a GM type axle would be required to have some type of axle retaining mechanism to race. I know that for drag racing a "C clip eliminator" kit is required.
That's about the limit of my knowledge, perhaps a bit over.


roverman
Art Gertz
Winchester, CA.
(2977 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: Full Floating Axles in road racing
Posted by: roverman
Date: November 23, 2010 03:04PM

I don't know if a "live axle", such as for Midgets and Sprint cars , are considered semi/full floating or "other" catagory.They sure are light and strong. My Huffaker GT1 came with full floating conversion on the Triumph housing. Now if we could just get those "special" inner sidewall tires, like Indy and Formula1 get.... roverman.


Bill Young
Bill Young
Kansas City, MO
(1337 posts)

Registered:
10/23/2007 09:23AM

Main British Car:
'73 MG Midget V6 , '59 MGA I6 2.8 GM, 4.0 Jeep

authors avatar
Re: Full Floating Axles in road racing
Posted by: Bill Young
Date: November 23, 2010 04:00PM

Art, from what I understand the definition of a full floating axle is one where the drive hub is mounted on it's own bearings and the axle half shaft is only used to transfer the drive from the differential to the hub. On the early style banjo axle used on the MGAs and early MGBs as well as the Spridgets, the hub assembly is mounted on the housing and the half shaft drives it through a flange that goes over the wheel studs. A similar type full floating hub uses a outer cap with a spline to engage the half shaft which is splined on both ends. That's the type axle used on big trucks and older sprint cars with quick change rears. Since the hub is retained by it's own nut and locking mechanism if the half shaft breaks the hub doesn't change, just loses drive. If you see new trucks being towed you'll usually see the half shafts packaged and strapped to the frame so that the differentials aren't rotating when it's being towed.
A newer lighter weight design for a quick change being used by a lot of sprint car racers now is an open tube design, where there's no axle tube over the shaft and the brakes, suspension take off points etc are all carried by an outer bearing carrier which also locates the axle shaft. I'm not sure how to classify that type.


taylorcraftbc65
Sabrina Hill

(4 posts)

Registered:
05/15/2011 01:14PM

Main British Car:
1963 MGB--1990 Jeep Wrangler-- 1987 Jeep Cherokee stock in MGB-4.5 Jeep I-6 in Wrangler- 3500 rover

Re: Full Floating Axles in road racing
Posted by: taylorcraftbc65
Date: May 15, 2011 03:16PM

I don't think that we could get away with full floating axles in ChumpCars, but I am running a Dana44 semi floating axle in lieu of
the Ford 8.8 out of an Explorer that I was going to use UNTILL I found out that the Ford used the same hokey "C" clip style axles as tha flimsey Dana 35's.
I have a friend who campaigns a TR-6 in ChumpCars that is eyeballing a possible axle swap, but no one knows to what just yet.
Brie


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