vacuum brake help

[WINDMILL]

I just change to vacuum brakes and this just will not hold under boost. i have 4 wheel disc brakes too. I have tee in to the pvc valve(is this ok). can not get old 2 to 3 lbs boost before it pushes the car forward. i have read alot of the post on the vacuum change over but mine does not seem to work good. any help on this before i take it back off.

sorry for the double post

 

[unix_punk]

You should get a better vacuum source and ensure the brakes have been bled correctly including pushing the plunger in on the prop valve on the frame for the duration of the bleed. I noticed I had better holding power when I moved my vac src from the pcv tee to one of the TTA style vacuum blocks.

 

[WINDMILL]

change

i wil change the vacuum sorce now and try that. will get back soon on that.

 

[86brick]

You should get a better vacuum source and ensure the brakes have been bled correctly including pushing the plunger in on the prop valve on the frame for the duration of the bleed. I noticed I had better holding power when I moved my vac src from the pcv tee to one of the TTA style vacuum blocks.

Good advice. I have the TTA style vacuum block on mine and can hold 9-10lbs of boost no problem!

 

[Nascarcamper]

Have you checked the check valve?

 

[ttypewe4jim]

also dont forget to try the old sy/ty trick.... right before you goto bulid up boost throw the car in "n" and give it a couple rev's while pressing the brake down hard... then just put it back into drive and start buliding boost

 

[WINDMILL]

none

i done what jim as done on the neutral thing. also has a new check valve in it too. it wont hardly hold 1 to 2 # of boost. i have some thing wrong. maybe the master cly is bad or something. the pedal is not firm like it sould be.

 

[unix_punk]

May need to bench bleed that mstr cyl and then re-bleed the lines after.

 

[WINDMILL]

done that

we have done that to, and let the line just run fluild out for a while to blead itself.

 

[87NAT]

Get the TTA vac block and go to the booster from the top of the TB. Whats your vacuum numbers at idle?

 

[WINDMILL]

thanks guys

well thanks for all the help on this brake deal. I just sprung for the hydroboost system from bob. i hated to do it, but i think it will be better in the long run for me. If anyone needs a vacuum setup mine is for sale. its works great reg driving tho, but not holding boost at the starting line for me.