Hughes Performance has taken torque converter tune-ability to a new level. This is thanks to the Pro Series Dump Valve System. The first stage dumps converter charge oil, effectively reducing the amount of oil in the converter, thereby affecting stall speed and other attributes. The second stage exhausts cooler discharge oil — oil that’s being discharged from the converter out into the cooling system. 

“This is a two-stage system — one that works by taking oil from the converter feed circuit and is completely internal,” Hughes’ Tony Kane explains. “This is the most effective, giving you anywhere from 200-800 rpm. An external stage then interferes with the cooler flow, restricting flow back to a jet orifice and into the pan. This is good for anywhere from 200-400 rpm, depending on the circumstance. It varies depending on the car, the efficiency, and how tight the converter is, but between the two of them, you have flexibility from about 200-800 rpm. They can be run in series, and they’re adjustable from that range with the different orifices that come with them.”

“Generally, if you have too tight of a converter, it will loosen it up,” continued Kane. “If you have a turbo converter and trouble with the stall, we’ve had racers knock off 1-2.5 seconds off their stall time to get right up on the converter right where it needs to be. And on the street, where the road is marginal, they can take some of the aggressiveness out of the converter by releasing the fluid. It also softens the hit without having to adjust engine timing or some other parameters. It’s like being able to tune your converter without actually taking the converter out of the car and opening it up.”

The system is relatively basic for the mechanically-inclined. The dump valves can generally be installed by the end-user. Hughes’ Dump Valve Systems can:

• Aid in reducing engine thrust bearing wear and tear.
• Increase stall speed while staging, in addition to faster engine response upon staging.
• Engage faster boost response with turbos and centrifugal superchargers.
• Reduce engine load in nitrous cars.
• Exhibit less RPM drop on gear changes.
• Used to manage wheel speed.
• Be fully tuned using a variety of jetting sizes.

Hughes’ Pete Nichols has produced in-depth technical looks at the Dump Valve System that explains their operation in great detail, which you can view below.