Optional M/C bore with servo

Hoghead

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I am redoing my brakes and thinking of using a dual circuit master cylinder simply for safety

This redesign will use 4 piston Wilwoods on the front
Rears are front Girling calipers on a custom disc arrangement I made in the 80's.
Wilwood adjustable proportioning valve in the rear circuit

I have a stock MK1 servo that I had rebuilt by Tiger Tom 15 years ago and unused. Undecided if I will use this or not.

So what bore for a master cylinder?
I see that .75" is popular with the stock pedal ratio, but not sure if others are using the servo or not

Wilwood make a 1" bore dual master with the correct mounting flange
PN 260-8794, but will this be too large?
http://www.summitracing.com/parts/wil-260-8794
 

0neoffive

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Hydro-mechanics

In mech-leverage speak; the larger MC bore will require more pedal efforts. There are several options for 3/4" tandems that will move enough fluid volume to keep things safe and not strain the knee cap. As for using a single line booster, it would best be served on the front line. The later TR GT 6 used this system method as an option and it worked so well that the rear brake shoes lasted forever.
FYI: If that booster has been sitting for all those years, you can bet that the internal seals are fully dried out and it's quite dead . . . . .
 

Ash31479

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I bought a dual circuit kit about a year ago. I didn't end up using it. It's the kit that Classic Motorsports Magazine installed on their tiger. It's a complete kit with the firewall spacer, the push rod is modefied, and the lines are bubble flared. It's ment to be run without the booster. Don't know how it would work with your specific disk set up, I was going to run it with the stock brakes. If you are interested PM me.
 

PITT40

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I put 4 piston Brembos of a Porsche Boxster on front and 2 piston Brembos off a different Porsche on rear. I tried 3/4 mc and it wasn't enough fluid to get the stopping power needed. Then I went to 7/8" and the pedal effort was too much for my liking. So I bought a 13/16" and like that the best. They are all Datsun/Nissan OEM units.
 

Theorangetiger

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Another Question

Along these lines, when comparing multi piston versus single piston calipers, would the total area of the diameters of the pistons be what really matters?
If you are moving four pistons versus one but the areas add up to be equal then would they require the same amount of fluid movement from the master cylinder?
 
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Hoghead

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570
I put 4 piston Brembos of a Porsche Boxster on front and 2 piston Brembos off a different Porsche on rear. I tried 3/4 mc and it wasn't enough fluid to get the stopping power needed. Then I went to 7/8" and the pedal effort was too much for my liking. So I bought a 13/16" and like that the best. They are all Datsun/Nissan OEM units.

I have a set of 996/Boxter S radial calipers in my garage and was wondering if they would fit?

Are you suing a servo?
If so fronts only or both front and rear?

Do you have the PN for the Nissan units?
 

PITT40

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531
Master that I bought was: Cardone 13-1839, fits 79-82 Nissan 210

I made brackets using angle. I put the rotor on and placed the caliper in place and took measurements from the radial mounting surface to the stock mounting holes and drilled those holes in the angle and trimmed them to fit where the factory machined the spindle. Then marked the radial mounts, drilled large holes that were close and refitted everything with long bolts and nuts through the radial holes. I put compressed air in the caliper to push out the pistons, then tightened the radial bolts. Then removed the caliper and tacked the nuts in place. Removed the radial bolts and final welded. That way I knew the calipers were aligned.

My calipers were off of a '97-'08 Boxster 986.
 

Hoghead

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570
That Nissan 210 cylinder is a .812" - 13/16 bore.
If your calipers are the same as my 996 ones the Brembo pistons are (2 x 40mm) + (2 x 36mm)

The Wilwood calipers I have in mind for the Tiger have 4 x 1.75"/44.5mm pistons
I now see others using a Nissan 15/16 MC but I only see this in a rebuilt version.

What wheels are you using with those Brembos
 
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PITT40

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With the geometry the required pedal pressure goes way up the larger that you go. I wasn't a fan of the 7/8" and I'm a pretty thick ex football player. You can try the 15/6" but i doubt you will like it. I have barely used 7/8" that you can have for shipping costs. Got anything that I may want?

That Nissan 210 cylinder is a .812" - 13/16 bore.
If your calipers are the same as my 996 ones the Brembo pistons are (2 x 40mm) + (2 x 36mm)

The Wilwood calipers I have in mind for the Tiger have 4 x 1.75"/44.5mm pistons
I now see others using a Nissan 15/16 MC but I only see this in a rebuilt version.

What wheels are you using with those Brembos
 

Hoghead

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Messages
570
With the geometry the required pedal pressure goes way up the larger that you go. I wasn't a fan of the 7/8" and I'm a pretty thick ex football player. You can try the 15/6" but i doubt you will like it. I have barely used 7/8" that you can have for shipping costs. Got anything that I may want?

You have a PM
 
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