whats up with power brakes

[mikess68]

the person that i got the car from last week put disc brakes on the front. it has power brakes. when you put foot on brake, it stops even and ok, but with No sign of "power" brakes. feels like you had the motor die and you have a hard pedal. i can find a bad vaccume but the vac line that goen intot he intake (elde intake 4bl) is very small diameter. like a match stick size. would this pull enough vacc to make the booster work. of do i have a bad booster? should the vacc line be hooked into rear plate of carb, or a place on the intake. I dont see anything larger on the rear of the intake for the booster line. the car also has two boster lines that run together at the booster and again just before the intake nipple. is that right? any help appreciated. tks :-D

 

[RedFish]

Should be a 1/4" diameter manifold vacuum port and line supplying constant vacuum to the booster and a check valve usually on the booster. A small supply line will create the same inch pounds of vacuum in a chamber so large but it would take a minute or so. Then you could use up the vacuum very fast.
Two 1/9" lines do not equal one 1/4" line either. It takes four of 1/8" to equal the volume of one 1/4". Hope this helps

 

[mikess68]

that helps a lot. the hole that the vaccum is coming from , you could barely put a match stick in it. a lot less than a quarter. the size i would think is the one that runs to the pvc valve. about that size is what i need...right? and then the vac line comes off the intake, and has a T and a smaller line takes off and they both meet up again at the boster on a 25Cent size plastic "stopper" with a nipple for both. wonder why that is that way? the boster will pull back when vacc is applied you can feel it. so it seems to be working. the intake has a port the size of the one that goes to the spark advance.. if that helps draw a picture. there is a plug in the back of the bottom of the carb i could take out and put a outlet there prob. what do you guys think??

 

[fishman]

that helps a lot. the hole that the vaccum is coming from , you could barely put a match stick in it. a lot less than a quarter. the size i would think is the one that runs to the pvc valve. about that size is what i need...right? and then the vac line comes off the intake, and has a T and a smaller line takes off and they both meet up again at the boster on a 25Cent size plastic "stopper" with a nipple for both. wonder why that is that way? the boster will pull back when vacc is applied you can feel it. so it seems to be working. the intake has a port the size of the one that goes to the spark advance.. if that helps draw a picture. there is a plug in the back of the bottom of the carb i could take out and put a outlet there prob. what do you guys think??

Seems like to me the little line that comes off the check valve should go to the cruse control. But like stated you need a larger line in. Try pluging the little line off.