What You Need To Know About Big Cam Brake Problems


Your vehicle’s engine is basically a huge air pump. To pump that air, it must first pull it in through the intake valves to where the piston will suck in the air to mix with the fuel. 

The piston then compresses air with each crankshaft stroke, creating an explosion that is sent through the exhaust valve.

One of the best ways of pulling in more fuel and air is to open the valve further, and that getting a bigger cam. 

This combination leads to more power for your muscle car. 

However, the disadvantage of having a bigger cam is the fact that your car’s combustion chamber would likely take all the air being sucked in, leaving everything external to that chamber, such as the brake vacuum booster, without enough air to function efficiently.

Since a bigger cam steals almost all charge of air coming into your engine, your power brakes are left lacking the boost required from the engine’s vacuum levels to function properly. 

You will have to apply a lot of pedal pressure for it to work, and even then, the vehicle still requires a substantial distance to come to a stop. 

This is the reason big cam has brake issues. 

This issue can be fixed by the introduction of an electric vacuum pump or a vacuum canister. 

This article deals with everything about big cam and how to get the best out of both worlds – higher speeds and excellent brakes.


Crucial to the safety of passengers and the functionality of the vehicle, a brake booster resembles a circular-shaped canister. 

It works with your vehicle’s master cylinder to provide higher pressure to the brakes, consequently reducing the amount of pedal pressure needed for braking. 

This device typically sits on the back area of the engine case, between the master cylinder and the pedal. 

It makes use of a vacuum to balance high fluid pressures in the braking system of a car, facilitating effective braking.

The vacuum canister plays a significant role in your car engine. 

It functions as a reservoir that helps maintain sufficient vacuum supply to the heating, ventilation, air conditioning (HVAC) system whenever the car accelerates. 

Its principal function however is to provide a constant supply of vacuum to the power brake booster. 

For this reason, the vacuum canister should hold enough vacuum to allow the brake pedal to have sufficient power to assist if your engine stalls. 

On vehicles that have a vacuum booster, the pedal of the brake when stepped on drives a rod into the master cylinder through the booster, activating the cylinder’s piston. 

The engine creates a partial vacuum in the vacuum booster on each side of the diaphragm. 

When you step on the brake pedal, this rod cracks open a valve, enabling air to enter the brake booster on one side of the diaphragm while simultaneously sealing off the vacuum. 

This increases the pressure on that side of the diaphragm, helping it push the rod, which will in turn push the piston in the master cylinder.

When you take your feet off the brake pedal, the external air supply is sealed off by the valve, and the vacuum valve is opened. 

This has the effect of restoring vacuum on the two sides of the diaphragm, letting everything return to its initial position.

If your vacuum canister wears out, you must replace it as soon as you can. 

When left ignored, it leaves your engine susceptible to damage. 

Why you require a vacuum canister to improve breaking

Vacuum canisters play an essential role in the car’s engine. 

It functions as a reservoir that assists in maintaining a steady vacuum supply to the HVAC system whenever the car accelerates. 

Its principal function is to give a steady supply of vacuum to the power brake booster.

Black Vacuum Canister Brake Booster for the Chevrolet Camaro

Most of the vacuum operated brake boosters need 18 inches of vacuum to function efficiently. 

The vacuum canister for the Camaro has an added reserve of vacuum for cars equipped with vacuum-assisted power brakes. 

Its vacuum reservoir holds up to the maximum vacuums possible from your vehicle’s specific engine; 

  • Perfect for vehicles equipped with big cams
  • Black painted steel coating
  • Connects inline with your vehicles existing engine-to-booster vacuum hose
  • Improves brake performance impressively

This Vacuum kit is comprised of 1 Brake Vacuum Can, the mounting bracket, other hardware and fittings.

Capacity’ 2 Liter.

Condition New. Haven’t been installed or used before.

Air Fittings size 1/4 NPS

Dimensions 127/5 x 165/6.5

Color Polished Chrome and Black

Made from sturdy lightweight aluminum, this vacuum canister is cleanable & reusable. 

There is a high volume drain tap for fast and easy draining. 

This makes it perfect for use all engine types – turbo engines, supercharged engines, and normally aspirated engines. 

While it can be used for the Camaro, its design is a universal fit to suit most cars. 

The canister is easy to clean, empty, and maintain and helps prolong your engine performance by removing carbon build-up.

Size and holding pressure

Vacuum canisters are available in various sizes with the sizes determining how long it’ll last. 

While you’ll feel it’s best to go for a really big one, you should be sure that there will be enough space to fit it into your car. 

The canister recommended above is of the perfect size for the Camaro and most muscle cars as it’s small enough to fit into the vehicle. 

No matter its space limitations, the canister is large enough to hold enough pressure for a lengthy use.


This Vacuum pump serves as a force multiplier, tripling, or even quadrupling the force of pedal pressure applied when you hit the brake pedal. 

The vacuum level should typically be around 15 inches of mercury (inHg). 

Usually, this amount of vacuum is not a problem if your car has stock camshafts with factory timing. 

However, when big cams are installed to boost performance, the quantity of vacuum produced becomes minimal. 

Big camshaft reduces volume due to the fact that it increases the time each valve is open while also raising the amount of overlap. 

This has the effect of optimizing cylinder filling at high speeds, however, it also reduces vacuum. 

Because of this, vacuum-assisted boosters, just like those found on the brake system of almost every modern vehicle, are not able to ‘assist.’ 

Consequently, the pedal effort required is significantly increased and the desired brake system pressure may never be achieved.

This is where the Vacuum Pump comes in; a Vacuum pump stores vacuum which is essential since cars with big cam do not have enough vacuum available. 

As explained above, without enough vacuum, you might hit the brakes and end up with a hard pedal with no assist.

 A Vacuum Pump is suitable for vehicles with big cams since it provides vacuum for the brake booster to function efficiently, doing so independently of any complex vacuum source.

Master Power Brakes offers a great electric vacuum pump Kit (PN AC9001K), also available on Amazon which fits your muscle car needs perfectly. 

This electric vacuum ‘pump’ is efficient yet small, being able to create the vacuum required to ‘boost’ a power brake system while letting the big cam have all the air it needs. 

This vacuum pump kit comes with everything required to complete its installation, with connectors and all components

Comp Cams Vacuum Canister

Part Number: AC9001K

 Electric Vacuum Pump Kit

 Included in Kit:

  • Electric vacuum pump with Silent Technology
  • Steel mounting bracket with shock absorbers
  • 10-feet of premium hose
  • OEM fuse and wiring harness
  • Wiring Diagram
  • Mounting template


Electric Vacuum Pump

The electric vacuum pump is utilized when the vacuum that is required for the brake booster is not sufficient or cannot be provided by the car’s propulsion engine. 

This particularly applies to hybrid, gasoline, electric, and diesel direct injection cars. 

Electric vacuum pumps ensure the efficient operation of the brake booster. 

Modern engine technologies like those found in hybrid or electric cars especially those with big cam installed are unable to build up sufficient vacuum pressure for all its needs. 

Therefore, an electric vacuum pump is required to produce an alternative or supplementary vacuum for these vehicles.

This extra vacuum pump further ensures your vehicle complies with the latest safety standards while supporting the reliable operation of the vehicle’s brake system.


· The electric vacuum pump supports all engine types

· Decrease in energy requirements due to on-demand pump operation

· Supports CO2 emissions reduction

· Independent of combustion vehicle engine technology

· Maintenance-free (self-lubrication, dry running, requires no connection to the vehicle’s oil circuit)

· Electric vacuum pumps support a flexible cars platform concept

Silent drive Vacuum pump

The disadvantage of a vacuum pump has always been the bothersome noise. 

You can now remove this noise from the equation with the Silent Drive Vacuum Pump. 

It provides the necessary vacuum required to properly run a vacuum brake booster. 

Using OEM quality rotary-style motor, irksome noise is a thing of the past. 

An additional benefit of the silent drive vacuum pump is the amount of time it takes to recharge. 

While most types of vacuum pumps may take a while to recharge, the silent drive vacuum pump has the fastest refresh rate amongst vacuum pumps, ensuring that you are not stuck with a soft pedal. 

Another great advantage of the Silent drive pump is its installation. Most units on the market require mounting of the relay and switch, but the silent drive pump’s design incorporates them in a contained module system.

Rotary Claw vacuum pumps

Rotary Claw vacuum pumps produce contact-free vacuum economically and efficiently. 

This is made possible due to the principle of internal compression used in the rotary claw design. 

This vacuum pump is based on a static compression system. Compression happens – in contrast to rotary lobes – internally by volume contraction. 

The claw pump consists of two rotors. 

These rotors turn in opposite directions in the compressor housing without contact yet observing very compact clearances. 

They are synchronized using a high precision gear. 

As these claws move over the axial suction and the suction connection inlet gas is dragged into the compression chamber. 

The gas is then discharged after being pre-compressed within the compressing chamber.

Rotary screw pumps

The ‘screw vacuum’ pump is comprised of two screw-shaped rotors, with a left-hand thread and right-hand thread. 

These screws turn in the compressor housing at very tight clearance without friction, synchronized via a high precision gear. 

It’s compression housing and the unique shape of the screws constitute the compression chambers. 

Due to the opposing rotation of both screws, the chamber connected is enlarged and the gas is conveyed into the compression chamber. 

The chamber then moves axially to the pressure side from the suction side. 

In a variable pitch model, gas is compressed at each pitch change and then cooled before the next pitch change, leading to greater efficiency.

As a result, the gas volume is reduced until the screw’s front surface opens the pressure channel and the pre-compressed gas finds its way through the pressure connection. 

This all occurs on the axial housing wall chamber on the pressure side.


One of the most relevant components in any vehicle’s engine is the camshaft. 

The camshaft – whether in an overhead or pushrod engine – controls the closing and opening of the valves. 

This, in turn, regulates the flow of fuel and air in and out of the engine, hence determining the engine performance, emissions, and fuel economy.

The top 2 most trusted Camshaft manufacturing brands are COMP Cams and Crower

Both brands received a rating greater than 90% positive perception from muscle car enthusiasts. 

More than 16 different camshaft brands were included in this survey and voters were allowed to select more than one brand. 

Consumers were asked to rank the camshaft brands based on the following criteria: 

 • Effective

 • Cool & Trendy

 • Easy to install

 • Economy product

 • Good customer service

 • Innovative/cutting edge technology

 • Great price

 • High Quality

 • Reliability

 • Trustworthiness

Both brands ranked 1st and 2nd respectively and therefore come highly recommended. 

  2. Crower Camshaft for Chevrolet

Signing off

This is what the big cam is and why brake problems occur.

We offered solutions and explained the physics of how these problems manifest.

If you are interested in learning more about other muscle car issues, here are some of the best batteries you can purchase for your Dodge Charger. 

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