LS6 Intake - Brake Booster Vacuum
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LS6 Intake - Brake Booster Vacuum Have an lq9 with BTR stage 2 cam and stick 317 heads, car is running but cannot get vacuum for the brake booster. Do not want to remove the intake and replacing the port on the rear, what other way can I get enough vacuum for my brakes?
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Sorry for lack of clarity! The issue is two pronged, another source for vacuum other than the rear port and it’s plugged to the rear port now and it’s not working.
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Inspected the rear port before installing intake, there were no visible obstructions. Connected the brake booster hose to the port and there is no vacuum. The hose is visibly flat and further confirmed when the car was initially moved.
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[QUOTE=01CamaroSSTx;20354850]The part that goes into the booster is like a check valve and only lets air go one way. if its not functioning properly and doesn't close that 's an issue.[/
It let's air in and not out like a check valve, that is why the hose is collapsed. Where the hose is connected on the motor it is sucking air not pushing air into the brake booster. What could cause this to happen? I am out of vacuum plugs on the LS6 intake.
It let's air in and not out like a check valve, that is why the hose is collapsed. Where the hose is connected on the motor it is sucking air not pushing air into the brake booster. What could cause this to happen? I am out of vacuum plugs on the LS6 intake.
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[QUOTE=Easyed;20354859] The idea is to let manifold VACUUM (not pressure) SUCK air FROM the booster via the valve that only allows air to move FROM the booster TO the engine, as vacuum would normally do.
The part that goes into the booster is like a check valve and only lets air go one way. if its not functioning properly and doesn't close that 's an issue.[/
It let's air in and not out like a check valve, that is why the hose is collapsed. Where the hose is connected on the motor it is sucking air not pushing air into the brake booster. What could cause this to happen? I am out of vacuum plugs on the LS6 intake.
It let's air in and not out like a check valve, that is why the hose is collapsed. Where the hose is connected on the motor it is sucking air not pushing air into the brake booster. What could cause this to happen? I am out of vacuum plugs on the LS6 intake.
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[QUOTE=G Atsma;20354932] If this is not happening then what’s a possible fix? Will an electric pump be the next course of action?
Last edited by Easyed; May 26, 2021 at 06:20 PM.
The BTR stage 2 camshaft won’t rob enough vacuum from the engine for your brake booster to not work properly. The hose being sucked flat is evidence of that. I’ve had to run a braided hose there in high vacuum situations, to keep it from collapsing. I’d try another hose. That nipple on the rear of the intake is your best source for vacuum.
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The BTR stage 2 camshaft won’t rob enough vacuum from the engine for your brake booster to not work properly. The hose being sucked flat is evidence of that. I’ve had to run a braided hose there in high vacuum situations, to keep it from collapsing. I’d try another hose. That nipple on the rear of the intake is your best source for vacuum.
The nipple on the rear of my MSD on my 434 was pointing straight back, and because of my firewall to intake clearance, I couldn’t get the hose on it for my brake booster, so I cut it off, filled it in, drilled a hole over toward the booster where it’s angled, and used a bulkhead fitting there with my booster hose. Works great.
Sometimes you have to outthink the problem. Never let it beat you.
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Purchased and installed new hose today, the hose did not collapse, but the brake pedal is still hard.
The engine came from a 2004 Cadillac Escalade ESV and an electric vacuum pump was standard equipment. Now, is the standard vacuum pump engine specific or intake specific? The Escalade had a truck intake with electrical pump and I am running a LS6 intake due to clearance. If the original setup ran an electrical pump, was it because the engine was not producing enough vacuum and it was required or was it because of the truck intake? Hopefully, this makes sense to the recipients.
Thanks Again for your answers and suggestions thus far.
The engine came from a 2004 Cadillac Escalade ESV and an electric vacuum pump was standard equipment. Now, is the standard vacuum pump engine specific or intake specific? The Escalade had a truck intake with electrical pump and I am running a LS6 intake due to clearance. If the original setup ran an electrical pump, was it because the engine was not producing enough vacuum and it was required or was it because of the truck intake? Hopefully, this makes sense to the recipients.
Thanks Again for your answers and suggestions thus far.
Brake booster may have a ruptured diaphragm. Have you you checked it to see if it holds vacuum? What about the valve that goes into the booster that the hose connects up to. It should allow air to move one way and not the other so if connected properly then the intake will be able to suck air through this valve.
Brake booster may have a ruptured diaphragm. Have you you checked it to see if it holds vacuum? What about the valve that goes into the booster that the hose connects up to. It should allow air to move one way and not the other so if connected properly then the intake will be able to suck air through this valve.
Im hoping no one gets caught up on all the “ruptured diaphragm and nipples” talk...lol