510 rear disc conversion brake issues/problems

[68Datsun510]

I wouldn't be surprised if you have to get a proportioning valve with the stock 510 MC.

 

I have 280ZX front brakes, Maxima rear calipers with 200SX rotors, 15/16" 280ZX MC and the brake balance is great.

 

I run an identical setup except i use a 7/8" master form an '80 200SX, works fantastically, Rear brakes are mounted upside down like the EDP pic from page 1.

[Datzun510]

Would you recommend the 1980 200sx Brake Cylinder instead of the 280z? and why mount the calipers upside down? is that how they should be mounted for better results?

 

I currently have 280z fronts and just got the Maxima rear... so I want to upgrade my master cylinder also. Witch master cylinder is recommended without a brake booster?

 

Would either the 280zx Master 15/16 or the '80 200sz Master 7/8 will work fine or is one better than the other?

[68Datsun510]

1979-81 280ZX, 15/16" bore, moves more fluid, faster with considerably more effort. You need to push harder.

1980-81 200ZX, 7/8 Bore, more pedal travel, but less effort required. Both have the proper line placement and bolt pattern. 

 

If you like leg day for braking, go with 15/16, if you like things a little easier, go 7/8"

[datzenmike]

I put a 7/16 on my wife's 13/16 (or 3/4?) 710 and the effort was surprisingly more. It was also an automatic so you had to use a lot of brake. The brakes worked just fine but it was solid like a brick and hardly any travel. Now this was with the stock caliper and the master was all I could find in my parts pile. If also moving to a larger caliper this evens it out. My 710 goon is 15/16" and Maxima calipers and I friggin' love the brakes.