Hey everyone. I am soon going to undertake the venture of swapping in rear disc brakes into a 79. I know that the thread size on the brake lines is different. How do I overcome this. Is it just the side toward the rear of the car that has the different thread? Or is it both ends of the hardline? Do I need to swap ALL lines and the newer master cyl in order to do it? Is there a write up that I missed on here somewhere? THANKS!

 

https://www.rx7club.com/showthread.p...ight=79+brakes

Ok, after forever of searching I finally found this.

I had no idea mazdatrix actually made a kit for this! I hope anyone else interested in doing the conversion finds this useful.

But does anybody know about the proportioning valve? Can I replace the master cyl and everything from a newer car straight to the old booster?

 

Transfer everthing from the FB but keep the SA brake booster. The FB brake booster is larger than a SA so it wont clear the clutch master.

 

Would I be better off replacing the booster, and the clutch master. Are the in the same locations? I am also going to install respeeds big brake upgrade, so I am either going to need to replace either those hard lines as well, or find the adapter to install THOSE stainless hoses. Anyone know where to get em? Bwaits says he's working on em, but I'm not sure if they are a for sure thing.

Also, I think I'll need the 85 drive shaft since it's an 85 rear end right?

 

Try it. then give us a full report.

 

Done this in my old '79. As I recall, it's not a direct drop in, but with a little routing of the mounting holes it works fine.

 

Yes, we have the lines for you to convert from course the fine. Hope we can get a few more guys on the 79-83 brake kit in order to get things moving for you.

The brake master mounting holes in a SA chassis are closer than the FB. this is why you can not use the bigger booster on the SA.

-billy

 

The FB brake booster is larger than a SA. If you decide to use on a SA, it wont clear the SA.

Slot the mouting holes on both brake booster and clutch master. This will allow you to can slide the clutch master towards the fender AND/OR slide the FB brake booster closer to the engine.

HOWEVER, clutch and pedals stay at the same place. so if you have done it, the push rods are tweaked or ****-eye.

Wacky maybe wacko but he doesnt believe in mickey mouse jobs. So wacky will leave the SA brake booster alone.

 

I completely understand Wacky,,, I don't want my car to be any way mickey moused! And I really appreciate the patience you guys show us *especially me* on here. I have no problem using the sa brake booster, although from what I've read it's weaker.

Also, I will need the 85 drive shaft correct?

Don't worry about time for me Billy. I've still got two months before I even get out of Iraq, so time I have. It's the knowledge I want!

 

If you are using an 85 diff, then you will need the 85 driveshaft as well. They changed the pinion flange in 83.

 

Thought so.. THANKS!

 

Have the Mazdatrix rear kit/lines, everything else stock SA and it works great!
Keep your head down over There!
Stu Aull
80GS
Alaska

 

Did mazdatrix let you order Just the rear set. I already have the front ones now, and I am switching to respeeds front brake upgrade so I would have TWO sets of useless front lines. Hehe. Hell of a price to pay for brakes.

 

We can supply you with all the lines you need so you do not end up with extra stuff laying around.

-billy

 

That's what I love to hear! The 85 master cyl will bolt up to the 79 brake booster though right?