Brake pedal axis on FJ40 (1 Viewer)

[SSCR]

Anyone know what the brake pedal axis is on a 75 and up FJ40? Trying to do the equation of what bore master cylinder I need with piston area of my calipers. Thanks

 

[B y r o n]

Why not just look for a master for your year FJ-40?

 

[Jdc1]

Why not just look for a master for your year FJ-40?

He’s building a restomod that is mostly aqualu, aftermarket axles and LS based drivetrain.

 

[SSCR]

Thanks Jdc1, yep running Wilwood calipers with a stock 40 pedal cage to a fj80 master, with my piston area and pedal ratio there is a formula to try and figure bore size. Thanks!

 

[Skreddy]

If the piston area of the calipers is known, as is the master with the fj80 parts, can’t you just rearrange the math to come up with the pedal ratio needed?

 

[SSCR]

I suppose so.... but I’d rather just buy a different master than modify the pedal geometry if I had to. I plan on going with a 1” bore but7/8 to 1.25” is readily available and simple bolt on.
This is the article I am referring to.

Effects of Master Cylinder Bore Size on Your Brake System

Follow this guide to learn how the change of bore size on a master cylinder affects a four-wheel disc brake system. View the conversion chart to figure the total bore area for your brake setup.

www.speedwaymotors.com

 

[B y r o n]

Not sure if this will help but I'm running 4 piston Wilwood's at all 4 corners with a FJ80 non-ABS master. Spec's I've seen state all FJ80 masters have a 1" bore. No problems stopping with 33-12 1/2" X 15 tires.

 

[SSCR]

That helps tremendously! I’m doing 6 piston but I believe the piston surface area is similar. Thanks!!!