[CWPASADENA]

Originally Posted by BRENT in 10-uh-C

Actually, I am of the opinion that you took away front braking instead of increasing it due to the amount of travel it now requires vs. the normal amount of rear arm travel. The brake pedal now must pull the arm further to apply the same amount of brakes on the front.

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Originally Posted by Bob C

I was thinking the same as Brent when reading what you did to the arms.

Bob

Originally Posted by Jason in TX

I'm going to also agree with decreasing the breaking action. By adding a longer arm, you decrease the force needed, but you have to also apply more movement.

Perhaps this would make more sense if you had lengthened the levers on the brake cross shaft. that would have pulled the stock lever further back. Or you could have also lengthened the push rod inside that pushes on the wedge.

Originally Posted by Bob Johnson

What did you do about the brake rod adjustment? To get the results you want you would have to loosen up the rear brake rods. The front to rear ratio is usually adjusted by the brake rods. If you shorten the front rods or lengthen the rear rods you get more front brakes. to get more rear brakes shorten the rear rods or lengthen the front rods. By lengthening the levers you have changed the distance that the break pedal has to move to to lock up the front brakes. Lets say it took 2" of travel for the brake pedal to go from a slight drag on the all 4 brakes to lockup. Now it will take 4" of travel to do the same for the front bakes. However the rears will lock up at 2" and the fronts will not be locked up. But if you lengthen the rear brake rods so the rear brakes do not start to drag until the pedal is 2" down. Then all 4 brakes will lock at 4" pedal movement.

Bob

I KNEW THIS ONE WOULD BE LOTS OF FUN !!!!!


Lengthing the FRONT actuating lever will result in greater torque at the pivot of the lever for the same force (pull by the brake rod) on the end of the lever. With greater torque at the pivot (in this case the actuator shaft), you have greater force at the end of the lever on the opposite side of the pivot (in this case, the little arm on the other end of the actuator shaft that pushes down on the push rod). You could also accomplish the same thing by SHORTENING the lever at the cross shaft. I found it easier to work with the front levers.

As originally designed, the front brakes contribute to apx 40% of the total braking of the car. By increasing the length of the front levers you do increase the FRONT braking by 50% but the total braking (Front plus Rear) by only 20% (beings the front brakes originally only contributed 40% of the total in the first place).

IE, As originally designed, if you applied a force (pushed on) the brake pedal to the point where you had 1000 Lbs. of total brake retarding force, 400 Lbs would be contributed by the front and 600 Lbs by the rear. (400+600=1000).

By increasing the length of the FRONT levers by 50%, you increase the amount of braking effort that the front brakes contribute to the total by 50%. Example, with the SAME PEDAL FORCE required to give a total of 1000 Lbs. in the above example, you still have 600 Lb of retarding force contributed by the rear brakes (because the pull on the brake rods has not changed and you have not changed anything on the rears), but now, with the 50% longer front levers, you have 600 Lbs (insted of 400 lbs) contributed by the front brakes (400+50% x 400=600) or (400 x 1.5 =600). Now you have 1200 lbs of total braking effort (600+600) for the SAME PEDAL FORCE as used in the first example (unmodified configuretion).

As far as adjustment is concerned. I adjusted the individual brakes in the conventional manner, THEN I equalized the side to side and front to rear braking by adjusting the length of the rods. I did this with the BRAKES WELL APPLIED but not locked up. I had the car up on my lift and the wheels off. I made an adaptor that will hook over the lug studs and used an old, beam style, torque wrench to measure the braking effort of each wheel. You can also do this by having the wheels off the ground and try to turn each wheel to check the drag of each brake. YOU HAVE TO ADJUST THE FRONT TO REAR BALANCE WITH THE BRAKES WELL APPLIED, just like you should do with an unmodified system.

It does take an additional 20% of pedal travle to achieve the same pedal force, BUT you also have 20% more TOTAL BRAKING.

If you were to lengthen the front push rods you are not changing any of the leverages. All that would accomplish is you would have to lengthen the front brake rods to rotate the levers further forward to be able to release the brakes fully. What you want to do is to have more force on the front push rods for any given pedal force.

My goal was to get the BRAKE BIAS closer to optiumun and also to increase TOTAL BRAKING EFFORT for a given pedal force.

Again, I am NOT saying everyone should do this BUT this is what I did and the results I got.

Chris