Even though my belt driven vacuum pump pulls a constant 28" of vacuum and self regulates itself I still use a canister inline, plus it is usually a good location to put a vacuum gauge to see what the pump is really pulling.
Help me with vacuum pump for brakes !
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It sounds like you loose vacuum the second you hit the gas, which is what naturally happens inside the manifold. The set up strikes me weird because you are pulling a constant vacuum via the pump. I think the pressure equalizes to atmosphere when you hit the pedal because you don't have a one way check valve between the pump and the booster.
I have a check valve unless the check valve is bad... i also only tested it thus far in the parking lot.
how long does the pump have to run to initially build 18-22" of vacuum ?
It shouldn't take long, almost instantly. From your original post, I thought the check valve was before the tee. I like to run mine close to the booster. You can try to run the check valve last, or the pump in line between the booster and manifold. It would help to have a vacuum gauge on intake manifold. On snap throttle, it should drop and rise quickly. Crowning throttle should only drop a little and gradually. Just to make sure you have no leaks.
You only have 25 deg of overlap with that cam. What are the specs on the new cam you are running?
sorry the check valve is in between the manifold and the T , then the right side of the tee goes to the booster the bottom part of the tee goes to the pump
The tee is still weird. You're basically running a non-beneficial redundant vacuum. I wouldn't run manifold vacuum to the booster because it isn't enough. I would try vacuum pump to check valve to booster. A canister/reservoir in line will help too. Other end of pump open, or restrict it.
yeah thats what me n my boy were talking about but its weird that the instructions were preferred for the T method but I agree with u ... supposed to go to the shop later and do some work on it so i will re-run it and see what happens...
If I have time I'll finally convert my GP to manual brakes for this year. With a proper master cylinder it doesn't take much more pedal pressure to stop the car and you much better feel on the brakes. We a had a skinny 15 year old kid driving our G body circle track car with manual brakes and he had no problem locking the wheels up and he never complained about his leg being tired after hitting the brakes twice each lap
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okay so vacuum pump is making vacuum,
i plumbed it with vacuum to check valve to booster and exhaust to manifold. if u start the car , don't touch the brake, go in reverse or drive u get a nice power brake stop, problem is if u hold the brake the vacuum isnt building fast enough to then stop the car in a parking lot scenario... now the car isn't on the road yet. is this a normal scenario? is something wrong? even when i plumbed it exhaust open, vacuum straight to booster i was having the same issue...
if I get a canister will this solve the problem or is this a common occurrence with vacuum power brakes?
I'm really at a loss right now idk what to do...
i plumbed it with vacuum to check valve to booster and exhaust to manifold. if u start the car , don't touch the brake, go in reverse or drive u get a nice power brake stop, problem is if u hold the brake the vacuum isnt building fast enough to then stop the car in a parking lot scenario... now the car isn't on the road yet. is this a normal scenario? is something wrong? even when i plumbed it exhaust open, vacuum straight to booster i was having the same issue...
if I get a canister will this solve the problem or is this a common occurrence with vacuum power brakes?
I'm really at a loss right now idk what to do...
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