• What is a Quick Drive, and how does it work?
A Quick Drive is a torque converter drive unit, which allows the use of several types of racing specific transmissions that were designed to be used with a clutch in an application where the racer desires to use a torque converter instead of a clutch. It contains a closed loop oil (ATF) circuit to fill and maintain fluid in the torque converter, a brake mechanism used to stop the transmission input shaft from turning (trans-brake), and a shaft to connect the driven member of the torque converter (the turbine) to the input of the transmission being used.
• What transmissions can I use with a Quick Drive?
The Quick Drive was designed to allow the use of most planetary type transmissions (B&J, Lenco, etc,). Additionally, adapters are available for other clutchless manual transmissions (Liberty Gears, etc.).
• Where can I get a torque converter for my Quick Drive?
Most racing / high performance torque converter manufacturers can build a torque converter for your Quick Drive. The converter builder will need to know what input shaft your Quick Drive has in it, as well as your combination of engine, flywheel (flexplate), and mid-plate thickness in order to build your converter to the correct height. We will happily work with any converter manufacturer to assist them in building your converter for you. Check our Links page for a partial list of torque converter manufacturers.
• Where do I get a bellhousing for my Quick Drive?
Bellhousings specifically for your Quick Drive or Quick Lock and meeting SFI specification 6.3 are available from most bellhousing manufacturers in a variety of materials (aluminum, titanium and steel). For those racers that are not required to use a bellhousing meeting the SFI 6.3 spec, we have an adapter available that allows the JW Performance Ultra-Bell Powerglide bellhousing meeting SFI specification 30.1 to be bolted to your Quick Drive or Quick Lock. These bellhousings are available through most high performance mail order houses (Jegs, Summit, etc.), as well as from JW Performance directly. Sportsman type (SFI 30.1) bellhousings specifically for the Quick Drive or Quick Lock are going to be available from at least one manufacturer in the not too distant future. Visit our Links page for a partial list of bellhousing manufacturers.
• I have a bellhousing or clutch can already. Can I use it with my Quick Drive?
In some cases, your existing clutch type bellhousing can be modified to be used with your Quick Drive. The standard depth of the bellhousing for a Quick Drive is 7 ½”, and for a Quick Lock lock-up drive unit the standard depth is 8 ½”. Check with both your bellhousing manufacturer as well as your torque converter manufacturer to determine whether modification of your existing bellhousing is a feasible alternative to purchasing a new bellhousing.
• How long is the Quick Drive?
The case of the Quick Drive is 7” long. This is the distance between the bellhousing and the transmission. You can find dimensional drawings of the Quick Drive in the Quick Drive Toolbox.
• How much does a Quick Drive weigh?
We have devoted much effort to building the Quick Drive as light as possible without sacrificing strength. A Quick Drive non lock-up unit weighs 49 lbs. without bellhousing, torque converter, transmission, or fluid. The Quick Lock lock-up unit weighs 51 lbs. without bellhousing, torque converter, transmission, or fluid.
• What is the difference between a Quick Drive and a Quick Lock?
The Quick Drive is designed to be used with a non lock-up torque converter. The Quick Lock incorporates all of the features of the Quick Drive, but is built to use a torque converter with an internal lock-up clutch.
• What is a lock-up torque converter, and what advantage does it offer?
A torque converter is a fluid drive coupling between the engine output at the flywheel and the input of your geartrain. As such, there is some inherent inefficiency in any non lock-up torque converter. A lock-up torque converter has, in addition to the three elements of any torque converter (the Impeller, the Turbine, and the Stator), a mechanical means (a lock-up clutch) of coupling the driven element (the Turbine) of the torque converter directly to the housing of the torque converter. This coupling or lock-up clutch, in effect, connects the engine output directly to the input of the transmission’s geartrain, thereby eliminating any potential inefficiency within the torque converter. It is essentially like having both a torque converter and a clutch in the same vehicle. The performance advantage depends on several factors, such as how efficient your torque converter is, how your “tune-up” works within your non lock-up converter combination, as well as the type of powerplant your vehicle employs (turbocharged, supercharged, nitrous assisted, naturally aspirated, etc.).
• Can I run a Quick Lock lock-up drive in my class?
It is your responsibility to check the rules governing the racing that you participate in. Currently, lock-up torque converters are prohibited in most classes of drag racing, with the exception of “Outlaw” type classes and some bracket / dial-in type racing. This is subject to change by the sanctioning bodies that make the rules. This responsibility extends to other forms of motorsports as well. Check your rules before deciding which type of converter drive to purchase.
• Can my Quick Drive be converted to a Quick Lock lock-up unit?
Only the most recent versions of the Quick Drive can be converted to a lock-up Quick Lock unit. If you already have a Quick Drive whose serial number (located on the rear of the Quick Drive case, just above the oil pan rail) begins with U52XX or higher, it can be updated to a Quick Lock. All other versions of Quick Drive are not able to be converted. Please contact us for more information.
• What kind of fluid does the Quick Drive require, and how much does it hold?
The Quick Drive works well with most any quality automatic transmission fluid, as well as some hydraulic fluids. Most performance oil companies offer high performance automatic transmission fluids in both conventional and synthetic formulations. We have found that a quality brand of Dextron 6, which is a full synthetic automatic transmission fluid that General Motors designed to replace all previous versions of Dextron, works very well in most applications, and is reasonably priced. The system capacity varies with the size and type of torque converter you are using, as well as whether or not you are using a cooler. Typical capacity for a Quick Drive non lock-up is approximately 8 quarts, and the Quick Lock lock-up units generally hold around 9 quarts. Higher capacity oil pan options are coming soon.
• Do I need to run a transmission cooler?
While it is not mandatory, we recommend the use of a cooler with either the Quick Drive or the Quick Lock. We have found that many types of race vehicles have very limited air flow under or within the body of the race car, and that the use of a transmission cooler may not reduce the operating temperature of the drive unit fluid. In those applications, we recommend the use of a transmission cooler incorporating a cooling fan. For those racers / applications where a transmission cooler is not feasible or desired, the cooler fittings on the right hand side of the Quick Drive or Quick Lock must be looped together with a -6 AN or larger hose.
• How hot should my Quick Drive or Quick Lock get?
The temperature of the fluid in the sump (oil pan) will not be as high as the fluid temperature inside of the torque converter. How hot the sump temperature gets depends on many factors, such as the efficiency (or lack thereof) of your torque converter, whether or not you are using a cooler, air flow across the cooler, etc. Generally speaking, in most drag racing applications, the sump temperature should not exceed 220 degrees Fahrenheit during a run. Once shut down at the end of a run, it is normal for heat soak to raise the sump temperature. Turbocharged applications generally tend to create more heat due to the longer period of time that the engine / converter spend at stall speed. It is not uncommon to see the shell temperature of the torque converter to exceed 300 degrees Fahrenheit after heat soak after a run.
• Should I cool my Quick Drive or Quick Lock between rounds?
Again, while it is not mandatory, we do recommend cooling the fluid in the Quick Drive or Quick Lock as soon after a run as possible. The greater the amount of time that any fluid spends at elevated temperatures, the more rapidly that fluid will begin to break down, resulting in diminished fluid properties, such as its shear property, ability to lubricate and inhibit corrosion, etc.
• How do I cool my Quick Drive or Quick Lock?
The proper method of between round cooling is to use an external pump / cooling system to draw fluid from the oil pan (sump), circulate it through a cooling medium, and then pump it into the “CONV” port of the Quick Drive or Quick Lock. This method will circulate cooled fluid through the torque converter and vehicle mounted cooler (if so equipped) as well as cooling the sump fluid. A properly designed cooling system can reduce the fluid temperature below 150 degrees Fahrenheit in as little as 10 – 15 minutes. There are many quality machines available designed specifically for this task. Visit our Links page for a partial list of manufacturers. Many racers have built budget devices to accomplish this as well.
• What is the Safety Sprag, and should I have my Quick Drive or Quick Lock built with one?
The Safety Sprag feature incorporates a one way clutch mechanism (sprag) within the drive unit. This one way clutch allows for torque transfer from the torque converter driven element (the Turbine) to the transmission input in the direction of engine rotation only. In other words, whenever the engine RPM would be less than the transmission input shaft speed (i.e. when lifting off the throttle at higher speeds such as after crossing the finish line), the Safety Sprag freewheels, or overruns, thereby allowing the engine RPM to fall to idle speed instead of staying at high RPM. While this feature can reduce stress on the rotating assembly of your engine, it also prevents any “engine braking” effect (having the engine help to slow the vehicle). The Safety Sprag has limitations (see features and specifications on the Quick Drive page) and is therefore not recommended for high horsepower (over 1600 HP) race vehicles, or those race vehicles prone to tire shake.