Dual brake master cylinders as in 2 anyone do it?

[Toyanvil]

I am still looking into running a dual brake system on my Ser II. I have a Toyota Prius brake master cylinder that should work, I just don't like the look if it. I started looking at running 2 Wilwood M/C side by side, this way I can run different size bores front and back. I think they will also look more period correct. Has anyone tried this? or know if it will work?
Here is the M/C

I am also thinking about welding a mount to hold one of these into my pedal.

And these on the M/C

 

[260Alpine]

Racers do it all the time. MGB usually run 3/4" on both and adjust the bias bar. Wilwood used to have instructions on the setup. What do you have for front brakes?

 

[Barry]

Wilwood used to have instructions on the setup.

They still do; go to http://www.wilwood.com/PDF/DataSheets/ds1102.pdf

 

[260Alpine]

Tilton has a video that may help:

https://www.google.com/search?q=til...rd=ssl#gws_rd=ssl&kpvalbx=1&spf=1517163150513

 

[DanR]

Toy, 65beam posted a PIC of a pair of Master Cylinders mounted side by side a few days ago in the Harrington post.

 

[sunalp]

John,
I'm using a dual master from a Nissan F-10. I sourced it from Rock Auto, if memory serves.
Here's a shot of it in the car with the V6.

Cheers!
Steve

 

[Alpine66]

John,
I'm using a dual master from a Nissan F-10. I sourced it from Rock Auto, if memory serves.
Here's a shot of it in the car with the V6.

Cheers!
Steve

That's the same one I'm using, works well.

 

[Barry]

Toy, 65beam posted a PIC of a pair of Master Cylinders mounted side by side a few days ago in the Harrington post.

A picture from the back side of the firewall would be a lot more interesting.

John,
I'm using a dual master from a Nissan F-10. I sourced it from Rock Auto, if memory serves.
Here's a shot of it in the car with the V6.

Cheers!
Steve

The F-10 unit is a tandem master cylinder. Dual master cylinder has a completely different meaning.

Just my opinion, YMMV.

 

[260Alpine]

Plus the F10 is hard to find now.

 

[Toyanvil]

I think it would be easier to find a unicorn then a F10 M/C. I am going to start with the spacing, wider would by better for the balance bar. 2.5 inches is what I need center to center, I think I am only going to get 2" if I am lucking. If I can get at less 2" I will weld a balance bar like this to my stock pedal and go from there.

 

[Toyanvil]

Tilton sent me a form to fill out to size the M/C s I will need. Anyone know the brake pedal ratio if a Series 2 or know how to do the math?

 

[260Alpine]

I believe the master cyl bore was .700. I know MGB was 4 to 1 for later power brakes and 6 to 1 for older manual. RX7 had 7/8 or 15/16 Master but when power brake usually they are a size larger. I bet .750 for your rear would be just right.
This thread has the math:
http://www.mgexp.com/phorum/read.php?40,2261400

 

[260Alpine]

If you are doing remote reservoirs, check this thread out:

http://www.ffcars.com/forums/160-modifications-originality/289042-girling-brake-cans.html

 

[Ken Ellis]

Toyanvil wrote: "I think it would be easier to find a unicorn then a F10 M/C..."
Summit lists them for $150 with a Feb 14 ship date... I put it in a cart, and it didn't squawk about unavailability. Lots of other Google hits, some of which may actually be valid...
https://www.summitracing.com/parts/...MI9-6rsuD-2AIVSrjACh1lQAwmEAQYASABEgLj5PD_BwE

Still Googling to find the unicorn, though.

 

[Toyanvil]

That's interesting, I have looked on and off for one over the years. When I would find one to order, they would require you to send in your core to rebuild. It looks like they are building new ones. I should know this week what size bores I need, if 3/4 will work front and back that would be an easy way to do it.

 

[PROCRAFT]

Tilton sent me a form to fill out to size the M/C s I will need. Anyone know the brake pedal ratio if a Series 2 or know how to do the math?

Check Wilwoods site they should have the info you need, its just a simple measurement from the pivot points. I scanned this in you'll get a little info from it doesn't quite fit in the scanner.

 

[Barry]

Tilton sent me a form to fill out to size the M/C s I will need. Anyone know the brake pedal ratio if a Series 2 or know how to do the math?

The math is easy; divide the distance from the top pivot point on the brake pedal arm to the center of the foot pedal by the distance from the top pivot point on the brake pedal arm to the MC rod clevis attachment point.

Measuring those distances is easy with the brake pedal arm out of the car and difficult with the brake pedal arm in the car.

On the brake pedal arm that came with my S-V, the distances are about 12" and 3" and the ratio is about 4:1.

No idea if my brake pedal arm is correct for a S-V or if the S-II brake pedal arm is the same or different.

 

[Toyanvil]

Thank you, my Series 2 worked out 4.23:1. I should know today what size bore I need for front and back. It would be nice if the 3/4" worked for both and I can pick-up a F10 M/C.

 

[Toyanvil]

It looks like a 3/4" will work with the brake pistons front and back. Thanks' to Ken, I have ordered a F10 from Summit. With this set-up I will use a Wilwood proportioning valve, this will also help with running new brake lines and brake light switch.

 

[Barry]

Toyanvil,

Neat looking hardware, but I am not clear about why you need a proportioning valve.

What performance benefit do you expect?