What to do to get vac. brakes to stop?

[2QWIK4U]

Since switching to vac brakes on my GN I've only been disappointed.There is no way that I can stop in a hurry.I have to follow at a long distance because the pedal gets very hard when you hit it.I had the vac line plugged into the pcv line and thought that may be the problem but I got a TTA vac port and moved it and still the same problem.This pedal is VERY hard after the initial applying the brake pedal.Do I need to put on a vac reservoir?Do I need to put the powermaster back on?I've bled them,adjusted and etc.
I know alot of people love the vac set up but it's not working for me.Could I have a bad booster?
Just looking for some new ideas........Thanks!!!

 

[mybuick]

see if the check valve is good and if you got the booster from a junkyard see if there is water in it. it will kill the diaphram inside the booster. i went through 4 of the boosters before i bought a new one for 40.00

 

[2QWIK4U]

What year car did you get the booster for?I changed the check valve,I ordered one from dealer for the TTA.

 

[tonka]

Put a vacuum gauge on the car and see how much vacuum you have...

 

[bruce]

Originally posted by 2QWIK4U
Could I have a bad booster?

Could?, yes.
It's starting to sound like you do.
The vac brakes have a slightly firmer pedal, but it's also more progressive, ie has more feed back feel to it.
But, your's is sounding, *way wrong*.

 

[kh440]

I'd agree with Bruce. Did the vac swap on my 87 T and yes the pedal is a little more sensitive (compared to the powermaster) it should have a fairly even feel to it. Did you swap over the pedal as well? What booster did you use and from where?

 

[jeff wilson]

put the powermaster back on, its a far better system than vacume, you cant compare it with the tta , its totally different, the only reason this vacume thing got started is because everyone is scared of the powermaster, these things get rebuilt for no reason, its mostly something very simple....

 

[bruce]

Originally posted by jeff wilson
put the powermaster back on, its a far better system than vacume, you cant compare it with the tta , its totally different, the only reason this vacume thing got started is because everyone is scared of the powermaster, these things get rebuilt for no reason, its mostly something very simple....

Ya, it's a great system, if you like one application failures. In just one stop you can lose all power assist with a PM with no indication there's a problem. Ya, great design.

Not to mention the reasonablely priced, and easy to get replacement parts for the PMs.

 

[scottyb]

When you switched, did you use a new booster?

 

[jeff wilson]

yes bruce you have a point,im just saying it works better.

 

[bruce]

Originally posted by jeff wilson
yes bruce you have a point,im just saying it works better.

IMO, the vacuums do work better. There is slightly less power assist and you have more feedback thur the pedal into what's going on. The PMs are more like an off-on switch and harder to do any threshold braking with. Not to mention that if they were to fail, you can still stop the car, in a reasonable distance.