not enough vacuum - Third Generation F-Body Message Boards

Nebu · 07-12-2005, 10:54 AM

hi,

i have my pcv and brakebooster with a t-fitting at the back of my double pumper. but the brakes dont get enough vacuum to operate properly. when i remove the pcv it works good.

how can i fix this? pcv is new. normally i would connect the brakes to the manifold, but i dont have enough room because of the carb.

nebu.

five7kid · 07-12-2005, 12:37 PM

You'll either have to move the carb up via a spacer, or find a way to get a fitting under the fuel bowl to the manifold.

This is exactly why many of us say not to T the PCV and brake booster together.

Nebu · 07-12-2005, 05:00 PM

i cant put a spacer on because i have no room left between the aircleaner and the hood and there is appr. 0.3" between the fuel bowl and manifold. i dont think there is 90° a fitting this small available.

is it possible to hook the pcv to the timed vacuum port?

Nebu.

zNucleaRz · 07-13-2005, 01:21 AM

If you have an Edelbrock intake these will help you.

Edelbrock Low-Profile Vacuum Fitting EDL-8096 9.95
Summit Straight Fittings 3/8 NPT to 3/8 Rubber Hose SUM-G3116 5.95

These are what I used I connect my brakes to this and the PCV to the carburetor.

IROC-Z28_CAMARO · 07-13-2005, 07:18 PM

I had the same problem. My cam is so radical it would not build up enough vaccum. I used one of those comp cams resovoirs and it works awsome.

Fast355 · 07-13-2005, 10:46 PM

This is on a FWD GMC motorhome but you will get the idea. It is a GM electric vacuum pump that is used to boost vacuum to the power brakes. The 1992 donor van that I used had one under the battery box of all places. I relocated it under the evaporator box on my 1983. My power brakes work great. Alot better than they ever did off engine vacuum alone.

http://www.gmcmotorhome.com/tech/vacuum_pump/index.html