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Rear disks?

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fordtrucks4ever

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I am looking really far down the road on this. Since my BE is still packed back in the dark corner. Can a front rotor be adapted to the rear axle with some machine work? I dont have the parts readily accessible at the moment to get a good baseline from. There are a ton of available rear calpier assemblies on late model cars now. So adapting a different rotor or some caliper shouldnt be a problem. Any input on doing something?
 
I have been dicussing this question here for some time now.

~HERE~ is a link to one of my previous questions about doing this (technically, I know it can be done....I'm also interested in finding out if it could be considered "stock" for racing).

Part of the real problem with Spridget rears is a design that allows outer axle flex: even the race axles ($300 each) break. And although the double-bearing race hub conversion helps, the chronic problem of oil weeping on the rear drum brakes still exists (due to sideloads). This Winter, it is my intention to swap the stock rear for a shortened Mazda RX7 rear. For about half the cost of building a decent Spridget rear, I can get the disk brakes and improved seals, stonger axles and limited slip in a better overall design. In my case, my club will allow me to run this setup....not sure this is approved for other races groups. For a street car, I'm not sure I'd bother with the disk brake setup.

A good source of info on this conversion is here:

https://the-mite.com/mite22.htm
 
In short, can the front disc be used in the rear, well I guess anything is possibble but no not really, remember the spridget front rotor bolts to the hub, which houses the wheel studs and the wheel stud bolt circle is actually outboard of where the hub bolts to the rotor. Winner Circle make a nice rear disc set up that uses what I heard is a Fiat 124 floating hat rotor, however it has no provisions for a parking brake and it mostly used for racing, however a mechanical operated caliper could be made up and designed to be cable operated as folks have done with some of the MGB rear disc set ups.

As for an alterante rear housing for racing, most vintage bodies and the SCCA do not allow this type of conversion. Some Spridget racers are now using hub set up off Dwarf race cars, this is a bullit proof set up as for as leaks and axle retention, but the parts flirt with a $1000 and you doing the work. As for breaking race axles, yes it does happen from time to time, most of the time it is driver induced and not a part failure. In 20+ years of racing these cars, I've only broken one racing axle and it was for sure my fault and the axle was atleast 20 years old. Some of the higher horsepower racing 1275s can actually break stock axle over time due to horsepower, but most of the time axles are broken when people do premature downshifting or go off course on bumpy terrain while under full acceleration, so in otherwords, driver error.
 
I am really interested in the Mazda mod, but don't have the equipment to make the mod as described in Nial's link. Would it be possible to take the whole rear-end to a drive shaft shop and have them make the mods? Would something like that be ridiculous expensive?
 
Define "ridiclously expensive" first.....Anything is possible: as Phil @ APT said to me when I ordered my engine "Speed costs money, how fast do you want to go?" I nearly swallowed my moustache when I got the estimate!!
You might look into Whoa brakes, I think that they have a conversion for the MGB, another is Frontlinespridget.com in the UK. I got my uprated axles and double bearings from them. I couldn't use the stuff from Winners Circle since I have a wire wheel axle.
 
I went to the Mite website before and leave always with the same thoughts, why did he do it that way, I'm not that impressed by his work. On his front suspension re do, he went to so much work to just hang a tube shock, for the amount of work he put in he could have made a coil over set up with much better gometry. he a good fabber, but needs to leave the design work to someone else.
 
Funny, I had a similar though about his radiator setup. Anyway, I admire him because he is doing it himself, and gets things done rather than just dreaming about it (as I've been guilty of doing)
 
Yeah, I could go on and on, it seems like he has this attitude to make everything himself no matter if it cost more than the traditional method and forget what anyone else has done even if it's the right way to do it. His lower control for example, he welded the spring pad in, which takes away any abilty to adjust the ride hieght and the fabbed lower control arm itself doesn't look like the coil spring will even seat in it. I'm guessing this is why we have not seen a finished product yet because there is not one. I don't think I would be looking for any ideas from this guy. Now watch him read this and want to kick my butt /ubbthreads/images/graemlins/smile.gif I don't know, it just looks like Dr. Frankinstien gone bad /ubbthreads/images/graemlins/smile.gif
 
But sometimes people like this stumble into something good, because they think outside the box. I've watched it with great interest. When he is done I think he will have a viable car, but not necessarily an improvement over the original design.
 
I, like everyone else on the forum, couldn't have more respect for the way you do things, Hap. And all your criticisms are of couse valid. But I also have to say I admire this Mite guy. If you read through his site, you will see that he is not afraid to rework things when he learns they need improvement. It's also very clear that he puts a lot of thought into everything he does. And he is having fun. I wouldn't be at all surprised if he does discover a few new techniques that many of us try.

At least he is not another one of these idgets who cuts open a perfectly good car in order to stick a 454 in there. /ubbthreads/images/graemlins/pukeface.gif



Now I am gonna get my butt kicked. /ubbthreads/images/graemlins/devilgrin.gif
 
Thanks Professor. That link gave me the input I was looking for. That narrowed Mazada rear would be easy enough for me to build, but I am sticking with the stock axle. There are enough rear disk ricers around, so it wont be hard to find somehting adequate for my conversion. If I find anything worth mentioning, I will pass it along. I do have stock Midget wires for the BE, which does simplify things a little. Again thanks
 
After scouring the pages at mites website, rear disks from Prelude seemed to be a good start. I dont plan to weld rear caliper mounts like he did, but machine a plate and bolt it to existing housing flange. That way it doesnt look like something has been severly altered from previous setup. I also want the front and rear to have a similar appearance thru the wires. I have a pile of nos pancake rotors from the 70's and early 80's I need to dig out and see if any is usable. Anything enlightening I will pass it on.
 
All the rear caliper mounts I seen for the racing rear disc set ups use the backing plate mounting holes, they are there, you might as well take adavantage of them.

Morris, don't worry, I'm pretty thick skinned /ubbthreads/images/graemlins/smile.gif Racing in SCCA production classes for what seems like forever, I've saw literally a couple of dozen coil over suspension designs, we even designed and sold a few ourselves. I've seen some pretty exotic fab work done to our little Spridgets, some better than others. The car in my avatar is a good example it is a Huffaker SCCA HP Bugeye, rumored to have cost $72K to build, I was lucky enough to get to drive this car for a season, talk about a space shuttle approach to a simple little car! Junkyard mentality has always been a part of hot rodding, some folks execute it better than others, some folks try to make it work even if it don't make sense. Neverhteless this guy (Mite) is atleast trying to make it all make sense, and it real easy for me or anyone else to step in at this point and second guess him, even if I don't agree with everything he has done, he still gets a big pat on the back from me for his effort.
 
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