Rear disc brake conversion?
#1
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Rear disc brake conversion?
I was wondering if it was possible to convert my rear drum brakes on my 85 rx to disc and if there is a kit that makes it eaiser.
#2
Umm, if you get the rear end from another first gen, it should bolt up directly. But you are going to need the ebrake cable/etc (don't know all the specifics)
Not to steal the thread but wanted to ask people if the GSL lsd rear will match up with my current rims (on a 79' drum). I know that the -SE has different dimension and that it wont work for that setup.
Not to steal the thread but wanted to ask people if the GSL lsd rear will match up with my current rims (on a 79' drum). I know that the -SE has different dimension and that it wont work for that setup.
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#10
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The vast majority of the time,the disc rears will have LSD.But after 25 years,there is the small chance that a 3rd member failed and was replaced with an open diff, in the disc housing.Also,there were a number of complaints back in the 80's about chattering LSD's and apprantly Mazda's fix was to swap an open 3rd member into the disc housing.....pretty lame,and lazy of them.
Again,its not very likely,but it is possible to come across one of these.
All 81-85 GSL 1st gens have smaller,solid discs in back with the standard 1st gen 110MM lug pattern.
The 84-85 GSL-SE has bigger,vented discs with 114.3MM lug pattern and a lower gear ratio.Axle housing is still the same,so it swaps in just as easily as the other rearends.
The 84-85 rears are more desireable if your making power,since they have larger axles and bearings inside.
Again,its not very likely,but it is possible to come across one of these.
All 81-85 GSL 1st gens have smaller,solid discs in back with the standard 1st gen 110MM lug pattern.
The 84-85 GSL-SE has bigger,vented discs with 114.3MM lug pattern and a lower gear ratio.Axle housing is still the same,so it swaps in just as easily as the other rearends.
The 84-85 rears are more desireable if your making power,since they have larger axles and bearings inside.
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I just had a guy tell me earlier today that 85's have LSD and disc rear but my 85 has rear drum and it only has single wheel spin when you really get on it. I know nobody has changed the rear end because I'm the 2nd owner. my dad being the 1st.
#13
From the factory, yes. There have been statements made on the forum that some of the buyers of brand new GSLs complained to the dealer about rearend noise/chatter. The dealers' solution was to replace the lsd unit with a pegleg one.
So it's possible find a disc unit with a non-lsd gearset, it's also possible to swap an lsd unit into a drum axle. Not possible to swap drums to disc, onto the same axle housing, afaik. Some of the IT7/ITA/SCCA/Roadrace guys in the race tech section feel that the drum brakes give better braking than the disc ones do. I have no opinion on that as I have not done any comparisions.
So it's possible find a disc unit with a non-lsd gearset, it's also possible to swap an lsd unit into a drum axle. Not possible to swap drums to disc, onto the same axle housing, afaik. Some of the IT7/ITA/SCCA/Roadrace guys in the race tech section feel that the drum brakes give better braking than the disc ones do. I have no opinion on that as I have not done any comparisions.
#14
Currently my inbetween a rock and a hard place,
I'm thinking about getting the complete rear from an 81' GSL, disk to disk/lsd diff, but the only problem is that the ebrake cable was cut. From all the threads that dealt with a rear end conversion it was named REQUIRED to have it, but none talked about what you can do if it was cut or if you don't have it. So what can I do? The guy selling the rear end to me gave me a pretty good deal, so should I follow through and find a company that will make a line for me/dealership or just wait for another rear?
I'm thinking about getting the complete rear from an 81' GSL, disk to disk/lsd diff, but the only problem is that the ebrake cable was cut. From all the threads that dealt with a rear end conversion it was named REQUIRED to have it, but none talked about what you can do if it was cut or if you don't have it. So what can I do? The guy selling the rear end to me gave me a pretty good deal, so should I follow through and find a company that will make a line for me/dealership or just wait for another rear?
#15
Black Dragon sells the e-brake cables, there are 5 different pieces to it. The first 3 parts from the handle back are all the same, it's only the last cable on each side that connects to the brake that's different. You're in luck. I just recieved my catalogue the other day and they finally lowered the price on the rear passenger side cable. It was outrageous before.
That depends on what your goals for the car, wheel and tire size, hp etc. How the motor is built and peak hp/rpm range will come into play when you get to that point too.
Originally Posted by brey
What would be the best ring and pinion (gear ratio) to buy for street and strip if I were to buy one.
#16
What rev limiter!?
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It's not "required" to have an e-brake cable,but if you dont get one, you obviously won't have a working e-brake. One other thing though is that you need some new brake lines that go from the single line to both brakes independantly, kinda like a "y" because drums use one line that goes to one side of the car, and from that side it goes to the other side. Which is why drum brakes on our cars only use one bleeder.
#17
Missouri has safety inspections before one can gt tags/plates, it's so nice to have a fellow rotorhead as an inspector, lol. As far as the brake lines, both rearends have a single brake hose going from the body to the rear end. My ss brake hose kit was a direct install when I swapped over to the lsd rear end.
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