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Limited Slip advice, scrapping idea of RX7 rear end

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bugedd

bugedd

Jedi Knight
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So I think I will stick with the stock rear end housing, but I really do want limited slip. Can anyone recommend what to use so I can start doing some research? And if anyone out there has something used, I'd be happy to take it off your hands :smile:
 
It might be cheaper to narrow a 7.5" ford rear end and order custom axles. Then you would have a wide selection of ratios and disc brakes if you wanted.
As the above add mentions ... there are different types of LSD and they work in different ways. Your selection will depend on the type of driving. Unfortunately, none of them are cheap.
 
Thumbs up for MiniSpares. Everything purchased there is good stuff..and yeah, shipping can be painful, so make a good full order, it'll still be better parts and a better price even with shipping.
Upside with the shipping? It's airmail..and usually you get it 3-4 days after you order!
 
Or start with a Mazda LSD to begin with.
 
I can't find a straight answer as to whether or not I can use the stock master with the 4 wheel disc brakes. If I can, and put in a proportioning valve, then okay. But so far all the conversions I have seen are running Tilton or other individual masters.
 
bugedd said:
I can't find a straight answer as to whether or not I can use the stock master with the 4 wheel disc brakes. If I can, and put in a proportioning valve, then okay. But so far all the conversions I have seen are running Tilton or other individual masters.
Click to expand...
Gerard's conversion will work with the stock master, but Joe at Sierra has just retired https://www.brakecylinder.com/spridgetbrakes.htm (explains why you must increase the size of the bore) Or you could go with the Girling replacement done in the sixities on the Sprinzel Sprites and use you old pedal box with some mods/
P_BOX_2.sized.jpg
 
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Well Joe has my master now, sleeving it to 3/4". Let me look around at Gerards solution, I didn't know there was one.
Apbos, do you know a guy down in your neck of the woods, Michael Souza?
 
Joe is the man for Gerards solution, he invented the kit! Mike Souza I have heard of him...............He is up in Mariposa I think about a 2 hour drive east.
 
Ya, interesting fellow that Souza is. I bought a roller from him that I am doing a shell swap with.
Do you have a link to Gerard's solution? All I can find is for front disc, not 4 wheel disc.
 
apbos said:
Joe is the man for Gerards solution, he invented the kit!
Click to expand...

Joe will tell you the idea and impetus behind this conversion was mine. I spent a lot of time sorting out the details and convincing Joe this would be a worthwhile endeavor, because it required his participation to make it happen. It was definitely a joint effort.

I will still be able to supply these master cylinder conversions going forward, if anyone is interested.
 
Another option would be to either modify or find a modified pedal box that uses 3 master cylinders and a balance bar. 1 for the front brakes, 1 for rear and 1 for clutch. That gives you the ability to tune the bore sizes for the front and the rear separately. The balance bar will allow you to adjust the bias front to rear. I picked up a pedal box off of ebay a couple of years ago that had the extra mounting point for the clutch MC to be mounted outside of the original pedal box and the balance bar for like $60.00. Im planning on running 5/8" MC's for the clutch and front brakes and a 3/4" for the rear brakes. I have an extra 1" MC too that I might use for the rear if the 3/4" doesnt feel right. Oh and I have a rear end from an '84 RX7 GSL with LSD and disc brakes that I am planning on using at some point.
 
Branson,

Is that car running yet? I thought you were close to being complete.
 
Jim,

very close to running. Seems like things just keep getting in the way of me being able to complete it. Hopefully I will be able to attack it this spring and have it running and stopping by summer.
 
I use Tilton 74 3/4" master cylinders on my bugeye on a modified pedal box, but you can use a 3 MC Tilton pedal assembly and add the bias bar. I find these on ebay from time to time in the $200 range.
HTH, Rut
 
I'm trying to stay away from that, so I'll use the stock rear end.
 
So if I were to use a pedal box with 3 masters, where could I find one that is more affordable than the Speedwell unit? I'm torn with the options. I want limited slip, which will cost about a grand to put in the stock housing. Or I can spend the money on a pedal box with independent masters, use the RX7, and get LSD and disc. Which seems that will cost a grand.
I'm trying not to go down the slippery slope of endless modifications. I rebuilt a ribcase, put that in, wasn't happy with it and did the Datsun conversion. I'm not in the financial position to do things twice like I did there, so I need to make sure I do it right the first time.
 
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