Shotgun Performance Transmissions
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Power-Glides with a after market deep pan the total amount of fluid, measured in quarts, That it will take to fill the transmission will approximately be the same number of inches and your Torque Converter.

For Example:

  • 8 Inch Converter it will take Approximately 9 Quarts (8.5 Litres) of Fluid
  • 10 Inch Converter it will Take Approximately 10 Quarts (9.5 Litres).

On a Th400 the total amount of fluid, measured in quarts, that it would take to fill the Transmission will approximately be 2 quarts more than the number of inches of your Torque Converter.

For Example:

  • 8 Inch Converter  it will take Approximately 10 Quarts of Fluid (9.5 Litres.
  • 10 Inch Converter it will Take Approximately 12 Quarts (11.35 Litres).

These are Approximate-starting fill depending on the Depth of the transmission Sumps (please make sure that you check the fill with a dipstick to confirm fill).

Danger: Never Spool Engine in Park, Doing so will cause serious damage to Engine and Transmission

First pull the car into the water, with a 3 speed transmission, put the car in 2nd gear, get the tires spinning then shift into high gear, this is preferred, but you can start in 1st shift to 2nd then to high gear, get into high gear as soon as possible. Pull away from the water fairly aggressively for a few feet, and then lift quickly off the throttle.

Place transmission back into 1st gear and pre-stage. When you are ready, stage the car into your racing position. Then immediately press the trans brake button, remember do not take your foot off the brake pedal wait a split second to give the trans brake time to engage.

If you are racing off the top bulb with a delay box, use the following procedure. After the car is staged and the brake is engaged – Concentrate on the top bulb only When you see the top bulb flash let go of the brake button, and then hit the accelerator. By pushing the accelerator after you let go of the brake button you will save a lot of wear and tear on your torque converter, and make the transmission run a lot cooler.

Note: When you leave on the top bulb I also recommend that you put your helmet against the head rest as soon as you stage your car and leave it there until after the car leaves the starting line, this is a lot easier on your neck.

If you are going to leave on the bottom bulb, after the car is staged and the brake is engaged – Concentrate on the last yellow bulb you will see the top bulb flash with your peripheral vision, when the first light flashes, hit the accelerator and then on the last yellow let go of the brake button.

Note: Always use a 2 or 3 step RPM rev limiter, most cars like RPM between 3,000 to 5,800. Find your car’s sweet spot. In most application higher is not faster.

Special safety note:
Never throw any 3-speed transmission into neutral when you cross the finish line. Leave the transmission in high gear as you slow down. The internal parts will spin 2 to 2 ½ times faster then the trap RPM and can cause internal parts to explode and exit the transmission, this may cause injury and or death, the exit of the transmission fluid may cause fire or loss of control of the car. Always run a shield and all safety equipment mandated by IHRA/Andra – Safety is no place to cheap out!

Check your shifter cable in each gear! Not all “shifter to bracket to transmission” installs will line up perfectly in EVERY gear. This will cause burnt clutch packs in the gear that is not fully seated!

Yes. The information your racecar shares with you is highly dependent upon the gauges you install. Two commonly overlooked, but very informative gauges, are transmission temperature and transmission pressure.

Transmission temperature is important in determining that sufficient heat has been built to send the car to the starting line. Over time, a range of average operating temperatures can be established for “before run” and “after run” readings. Transmission temperature can be an important factor in your search for ultimate performance and/or consistency. Any excessive high or low temperature condition should be noted, and might help to indicate a present or future problem.

The addition of a transmission pressure gauge can not only reinforce what the temperature gauge is telling you, but also provides information about instant damage, and normal operating wear occurring in the transmission.

For a transmission temperature gauge, look for one offering a high range of about 225-250 degrees. Ideally, the sending unit should be located in the pan to provide the most stable source of temperature. If a dedicated transmission pressure gauge is not available, an engine oil pressure gauge offering about 200PSI will work well. Most popular transmission used in drag racing, both late and early, have pressure sources that are ideally suited for this purpose. While originally provided for temporary dealer diagnostics, it can also be plumbed to provide a permanent information source. Your ATI technician can supply you with further details.

Always check your transmission fluid level after thoroughly warming up the vehicle. Levels will read much higher when warmed than when cold. With your car on jack stands, run it through each gear and reverse. Then put in neutral and check at idle. Right in the middle of L and F is perfect.

There are five things that could keep your transmission from moving in any direction

  1. Pressure regulator valve in the valve body is stuck open
  2. Broken front pump gear
  3. Broken Input Shaft
  4. Sheered splines in the torque converter turbine
  5. Pin on the linkage that moves the manual valve in the valve body is out of the slot on the valve, and not moving the valve to direct pressure to the band or clutches.

To verify pressure, remove a cooler line and start the motor and see if the pump is pumping fluid. If it is, pull the pan and check that the manual valve is moving with the shift linkage.

Always look for a converter to be full (generally about a quart +/-) before installing on the trans. Likewise, always fill the transmission with approximately 4 quarts of fluid +/-.

And don’t forget the engine, rear, etc. It’s easy to do after a new build or rebuild when everything is reinstalled and ready to go.

When doing a burnout, try to avoid dry hops, tire hop and wheel shake – a major factor in broken driveline components. Although it is not always possible, avoiding this behaviour will extend the life of many parts in your vehicle, alas it may not preferred when spinning the tyres with mates at the track

First, spin tires slowly in water in order to get them wet while avoiding soaking the wheel wells.

Second, pull to the front edge of the water using Low to High for Powerglide, Low to 2nd to high for Turbo 400, Ford C-4 and C-6, and 2nd to High only for Torqueflite and Turbo 350.

Thirdly, when the tires are hot enough, release the line lock and power the car out of the water 5 to 10 feet and lift. Avoid hook up that will scuff tires.

Finally – Stage immediately! Dry burnouts reduce traction and consistency. If you do not believe this, pay attention to your first dry leave behind the line. It will hook solid every time. Small amounts of water left on the tires will dry completely from the tire heat long before the green comes on.

No!! Shotgun Performance strongly recommends that you do not conduct stall tests. Stall tests break parts, and not just converter and transmission parts. Remember, you are at Wide-Open Throttle (full power) and maximum load. The pistons, pins, rods, and crank will really take a beating.

Many racers ask why it is okay to leave the line at Wide-Open throttle, but not okay to do stall tests. The difference is this – when at the starting line at wide-open throttle, you release the brake and the RPMs accelerate from that point. In the converter, the stator is locked via the clutch assembly (sprag) and goes from maximum load in a controlled constant reduction in force to zero load (free wheel) as the car accelerates. The hydraulic forces in the converter are directed in a smooth and efficient manner for maximum torque multiplication and flow for adequate cooling. When performing a stall test at wide-open throttle (or even with a rev limiter such as the MSD Two-Step), you lift off the throttle and the RPMs, now at 5,000 or 6,000, get jerked down to idle. The stator and clutch assembly goes from maximum load and torque multiplication to zero load in an instant. The clutch is unloaded rapidly and the hydraulic forces are instantly disrupted into unknown flow paths due to the rapid reduction in torque.

We have seen many converters damaged by this rapid unloading when a ring and pinion, planetary gear set, or input shaft fail. The rampant hydraulic pressure actually breaks the pump blades (fins) completely off the converter pump.

It is for this reason that converter manufacturers have for years warned against “snagging the slicks” coming out of the water as RPMs can go from 5,000 or 6,000 to an idle as the tires catch. Once again, damage can be done to the sprag assembly. Also remember that the converter builds up a tremendous amount of heat in a short period of time. By not running an engine after a stall test, all that heated fluid lays in the converter without having a chance to go through the cooler. Excessive heat eventually “fatigues” the metals in the converter.

So, just say no to stall tests. They damage parts. Use the transbrake ON THE STARTING LINE ONLY – not in the pits, not in the driveway, not for your burnouts – AT THE STARTING LINE ONLY! Your cost per run will diminish significantly.