Why Upgrading Your Pump for Hydroboost Is a Smart Idea
Hydroboost braking systems are becoming a more popular upgrade option for many older vehicles on the road today. This includes hot rods, street rods, muscle cars, and even some performance race cars.
Most brake systems provide assist through vacuum pressure created by the engine, but with hydroboost, the job of braking assist is placed on the power steering pump. The pump now has two jobs: provide steering assist AND provide braking assist. This puts additional strain and demand on the power steering pump, especially when the vehicle is braking and turning at the same time.
Very few OEM vehicles had hydroboost brakes from the factory, and therefore very few OEM pumps were upgraded to handle hydroboost. This means that the vast majority of pumps don’t have enough “muscle” to handle this added responsibility. What happens when a pump doesn’t have enough muscle? Let’s explore a few common issues that are a result of adding hydroboost.
Common Hydroboost Issues
1. Pump whine from a poorly designed reservoir. Pump noise is probably the most common complaint we hear after someone has added hydroboost. The noise can actually be caused from a few separate issues, but a bad reservoir is typically the most common. Poor reservoir designs allow the fluid in the reservoir to cavitate, which is when air bubbles get into the fluid. When air reaches the pump, it will create noise. It will also cause a lot of premature wear and tear on the pump, so cavitation should be avoided at all cost! The only fix for a bad reservoir is to change it to a good reservoir design.
2. Pump whine from a lack of pressure capacity in the pump. You may first want to read our article on How Pressure Capacity works. Pressure Capacity dictates how much “muscle” the pump has, and adding pressure capacity does not hurt the system, as is often misrepresented all over the internet. When a pump is is reaching it’s maximum pressure capacity, it can emit noises or whining. The fix for this is to up-tune the pump to have added pressure capacity. This ensures the pump can handle the extra workload of braking assist AND steering assist, and provides reassurance that you will never lose assist in a hard braking or corning maneuver.
3. Intermittent or complete loss of steering or braking assist. This happens because the pump doesn’t have enough muscle to power both systems when they are under load. This may not happen under casual driving conditions, but it is very likely happen if you have to slam on the brakes hard and turn the vehicle. The power steering pump is maxing out it’s pressure capacity and physically cannot push fluid down the hose (this is called pressure relief mode). The result of losing steering and braking assist could have severe consequences for driver reaction and vehicle control. This is NOT when you want your pump to fail you, and this is the reason we always recommend upgrading the pump to a higher tuning specification for hydroboost applications.
The Solution
Turn One’s line of Hydroboost-ready power steering pumps are built and tuned to handle the additional demands of braking assist. We overbuild our pumps so that they will never experience pressure relief under hard braking and turning, meaning that the pump will not fail you when you need assist the most.
We offer multiple configuration options, both standard and custom, to make sure you have the correct pump and tuning for your exact vehicle.