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Rear disk brakes ??????


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Rear disc don't work any better than drum brakes in the rear, front does most the work.

I suppose rear disc is good for bragging rights once one gets the whole thing set properly with proportioning valve and e-brakes, but a lot of work for bragging rights.

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That's an interesting theory. Disks don't fade due to water or heat .

The actual reasoning is that brakes on the roadsters aren't the best to begin with , expensive to  service, and after siting for better than 20 years need to be gone through.

Why not upgrade now ? Just my thoughts.

I know what needs to be done, where to source the parts, how to do the work. Just interested to here from someone who has actually converted a roadster to pick there brain.

 Thanks for responding Wayno . I do appreciate your opinion.

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I drove my Roadster for years as a daily driver with a shitload of stuff packed in it and on top of it, it was grapes of wrath looking with my bike, large tent, Coleman stove, fold down chair, sleeping bag, hanggliders and harness among a lot of other stuff that would not fit in the Roadster cab, I used to drive from Vancouver WA to Chelan WA all the time(every weekend during summer) with all this stuff, I put over 30,000 miles a couple years on that Roadster driving there and retrieving my hangglider equipment after hanggliding flights(sometimes over a 100 miles out), I drove over 2 major passes getting there and back(Snoqualmie and Blewett passes), I drove Blewett pass at night(favorite pass road) like I was running away from the cops and my brakes never faded although truth be told I was not using the brakes much, I also drove up and down mountain roads to get to hangglider launches although it was better if I found a ride up because my roadster was low and really wasn't meant for them kind of roads(scraped bottom a lot), I have never had brake issues in that car to this day(in my garage), it was fun to drive my Roadster this way.

The only issue I ever had with my Roadster was the fuel pump diaphragm got a hole in it on a Sunday evening in the North Bend WA area, and twice while going way to fast on the east side of Snoqualmie pass that rubber piece on the driveline slip joint expanded and started hitting the tunnel, I thought I blew the transmission up the first time, I made it twice from Vancouver WA to Chelan WA in under 5 hours(average speed was over 66mph for 329 miles), I liked driving at night because of no traffic so I could drive faster.

I can never recall my brakes ever being an issue, I have a U20/5spd in my Roadster.

1967_datsun_roadster.jpg

I believe that most guys that have upgraded their rear axle went to the RX7 axle with a LSD.

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The rx7 LSD is an interesting idea. Hadn't thought of it. I'll have to look into it.

Back to the brakes. you defiantly have an angel on your shoulder loading a roadster that way.

For the cost of rebuilding the rear brakes on a 69 R 311 I can convert to discs and fill a keg of beer. I like beer. and I like really good brakes.

If I was restoring the roadster I wouldn't even consider it . I'm not. I live in Astoria. The nearest straight road , other than 101 between here and seaside is miles away.

I drive 202 and hwy 47 to Vernonia weekly. What a cool road!!!!! If you plan to make good time on that stretch of road, you need good brakes.

For me ,  it's a no brainer.... Thanks again.

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I should have said narrowed RX7 axle with LSD, I think I seen one on craigslist a couple years ago for $900.00 in the Centralia WA area.

Everything about Datsun Roadsters is expensive, I went thru mine in 1995 just before prices for parts went thru the roof, I still dumped thousands into it, I did 90 percent of the work myself because I could not afford to have someone else do the work after buying the parts.

I got real lucky on the engine I have in it now, I bought a 20+ year old rebuilt engine that sat around and got water in one of the cylinders, I had that cylinder bored and a sleeve put in it, everything in that block was brand new, and I mean everything, I paid $500.00 for the block and spent less than $500.00 having it fixed, I ended up with a fresh U20 block for under a thousand dollars, and I sold my old block over a year ago for $750.00 with a fresh head, it ran but made timing chain noise when cold.

You motivated me today, I started and warmed up the Mini and Roadster today, I pulled both of them out of the garage under there own power, and put them back in under there own power also, the Roadster has not been out of there in a couple years now.

I believe Mike Klotz made a front disc brake balljoint kit for the Roadsters to get away from the expensive front ball joints/Roadster brake parts, if your going to have to redo them I would message him before buying all the expensive parts.

What is expensive about rebuilding the rear brakes on a Roadster?

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Spriso has a lot of info on their website about the RX7 LSD swap.

 

I think they still do the conversion, or they used to. I do know they rent out the jigs to do so.

 

Google spriso Motorsports. Lots of SR20 to roadster stuff.

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Datsunrides  Did you use the 200sx calipers and rotors? how'd you like the end result?

I have a small but functional machine shop  so the actual work is not the issue .

I only want to do it one time though. If there is a better conversion I'd like to here of it.

Wayno . Hey buddy , thanks for the info..... Check the price of the rear cylinders now.

 Datsun parts Inc. NOT THE CHEAPEST PARTS SORCE But a decent representation.

1969 311 rear brake shoes $140 + core

1969 311 rear cylinders $185 + core

1969 Drums $129 ea  + core

correct 1969 311 2 reservoir master cylinder $640 + core

Wow.

I can nearly convert to a full brembo system for the cost of rebuilding the stock roady brakes front and rear.

 

 I'm glad I have planned a resto mod.   

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The end result is just fine. I used brand new 83'-84' S11 rotors/calipers/brake hoses, and parking brake cable as even 8 years ago they were not easy to find used. If you can find a parts car the caliper brackets are a bolt on, but as you will see in the pics it is not hard to fab your own brackets. You will also either need to cut off most of the backing plate or fab a simple plate to retain the wheel bearing if you completely remove the backing plate, which I did since I was replacing the wheel bearings anyways. Make a couple new brake lines up to go from the splitter to connect to the flex hoses and make a couple brackets to attach to the axle. If you want to keep the parking brake function, you will need to fab a bracket to mount the S11 cable assembly. Not too hard to do. At the time I did this originally I had made up a template for the caliper bracket, and had a CAD drawing for the bearing retainer and parking brake bracket, but those are long gone at this point. You may need to upsize the brake master depending on how you like the pedal to feel. Couple pics attached.

 

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Datsunrides wooooooohoooooo! That's exactly what I needed . Thanks . I should have no problem reverse engineering from your pictures. Thanks a ton.

Nicely done.

Did you use an adjustable proportioning valve?

I,ll probably use a Subaru WRX 7/8" master. I have used them on other conversions with really good results.

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I am using the stock valve and have no issues, but it would not be a bad idea to use an adjustable one. My car is a 66’ so it is a single circuit car. The stock 13/16 master had the pedal too low for my tastes and the next largest I could find was a 15/16 which now the pedal is at the top but requires more effort, so a 7/8 should be a sweet spot. If I had the room I would go with a 7/8 dual circuit but there is this turbo thing in the way.

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