DAYTONA Sports Car Upgrades/improvements

[Aussie Mike]

I've given this some thought and I think the main problem with power steering pumps and racing is that they are just spinning them too fast. A PS pump will last 100,000+ KM in a road car but it's running at the RPM it was designed for which is pretty similar to the crank RPM so about 1800-4000 RPM. In a race car it's running 7000 RPM + which are speeds they are just not designed to sustain.

Also think about how they operate, the pump makes enough pressure to overcome heavy steering loads at low speeds while parking. At this time the pump is probably only just above idle. That tells me that running at higher speeds means the bypass valve will be constantly shunting all that extra pressure away and generating lots of heat. Just wasted pressure

The answer is to severely under drive the pump. I settled on running a 25% under drive harmonic balancer which was the biggest under drive I could buy off the shelf. I've also machined up a larger PS pump pulley for a bit of extra under drive. Add to that a decent cooler and probably some synthetic fluid and I reckon the PS pump should survive extended abuse.



The advantage of the Electric PS pump is they produce a constant pressure with the pump only really bypassing pressure when there is no load on the steering.