Pro Street & Strip . . . Turbo 400

Maximum HP Rating: 550
Maximum Torque Rating 525
Standard Gear Ratio: 2.48/1.48/1.00
Optional Gear Ratio: 2.75/1.57/1.00 & (others available)


For hi-performance vehicles.
For proper operation all vacuum lines & kick-down components must be used.
Factory automatic type shift pattern & manual hold operation.
Complete unit comes with general installation instructions.


  • Significant Slippage Reduction
  • Higher Torque and Thrust Capacity
  • Improved Oil Circulation
  • Hi-Capacity Filter

Competition Components

  • Sprag - Cryo-treated 34 element
  • Hi-Perf. Auto/manual valve body and Pressure regulator
  • High Performance Clutch Packs


OptionDescriptionRacer NetList Price
-FMFull Manual - Forward shift pattern$232.30$273.70
-BK-MSFI Bellhousing adapter kit installed....Mopar (includes flexplate, crank pilot)$891.25$978.65
-SD-SCast Steel Direct Drum w/36 element sprag$1,345.50$1,583.55
-GSHD Low gear planetary set...(2.75/1.57/1.00)$1,070.65$1,259.25
-BLSFI Bellhousing- installed for GM$388.70$456.55
-DSDip Stick & Tube (cadmium plated w/ locking top - specify engine)$79.35$93.15
-AKCNC Adapter Ring - GM to Ford...w/flexplate & crank pilot (Specify engine size & balance)$652.05$767.05
-CK700R4 to Turbo 400 Conversion Kit - 4WD...(incl. Sp Output Shaft, Tailhousing Adapter block, Dip Stick/Tube)...Now available for C4 Corvettes (call for pricing)$0.00$0.00
-BKSFI Bellhousing Adapter Kit- Ford (includes flexplate and crank pilot)$807.30$949.90
-DPDeep (steel) Pan & Filter extension$196.65$232.30
-CSKCenter Support Kit (w/split bronze bushing)$185.15$217.35


Part Number Racer NetList Price
Pro S/S Turbo 400 Chevy
Core Charge: $218.00
Pro S/S Turbo 400 Buick-Olds-Pontiac
Core Charge: $136.25

Order Notes

Fill out the "Converter Application Form" to determine correct converter size & stall rpm. All transmissions with converters and related equipment will ship by Freight in a special container.


SizeConverter TypeStall RangeMax HorsepowerMax TorqueRacer NetList Price
12"Towing Heavy Duty - Low Stall1300 - 1600 RPMs375300$280.60$330.05
12"Stock1500 - 1800 RPMs375300$233.45$274.85
12"Street/Strip1800 - 2100 RPMs400350$299.00$351.90
12"Street/Strip2000 - 2500 RPMs400350$353.05$415.15
10"Street/Strip...low torque2800 - 3800 RPMs600425$589.95$693.45
10"Street/Strip...high torque2200 - 3500 RPMs650550$807.30$949.90

When should a Turbo 400 be considered over using the Turbo 350?

Generally a Turbo 400 is preferred when the motor is producing more than 500hp and greater bottom end torque. This is typical with stroker motors and big blocks.

What are the hp losses through a Turbo 400?

Many have tried to approximate the answer to this question. The solution lies in how fast the heavier internals of the transmission are forced to accelerate. For instance, the hp loss is greater when accelerating from idle to 4000rpm in 2 secs. than in 4 secs. So, for ordinary driving the losses are negligible when compared to other transmissions. In race cars which are asked to accelerate much faster the percentage of hp loss becomes more apparent. The acceleration rate of a small block versus a big block also varies because the bb develops more bottom end torque sooner. The hp loss would be more noticable with the sb if both engines were accerated at the same rate. To significantly reduce this loss in a Competition TH400, we offer (3) aftermarket Alum. drums which reduce the rotating mass.

What is the weakest link in the Turbo 400 in Hi-performance applications?

The most common hardpart failure in this trans is the "34-element" intermediate sprag. Each time the trans is shifted into 2nd gear the direct drum applies a load to the sprag elements. When these elements are unevenly loaded (due to uneven drum rotation) eventually these elements will fail. To correct this uneven drum rotation we've developed the "Center Support Kit". With the addition of this option the drum will provide a more evenly distributed load on the sprag elements and eliminate premature failure.

Is a Deep Pan availaible for the Street/Strip TH400?

Yes, there is an "optional" steel deep pan and filter extension available. This option is normally included with the Competition full manual TH400 units.

Why would I need or want to use a lower gearerd Turbo 400.

The "low-gear" (2.75) planetary gear set offers a 11% increase in 1st gear over the stock ratio. As an example, with a 3.73 rear the car would launch as if it had 4.10 gears. It generally improves the launch capability of all cars with a higher rear axle ratio. This has a real advantage for vehicles weighing more than 3500lbs. This option can also be used to reduce the rear axle ratio by 10% or more to lower engine rpm at highway speeds and improve gas mileage.

What kind of transmission fluid should I use?

For Street and Street/Strip applications we only recommend the use of Ford type "F" Transmission fluid. For Extreme Duty applications we only recommend the use of ULX-110 type fluid. Both of these fluids are natural Petrolium based. Both of these fluids contain zinc which is the primary additive for proper lubrication for high performance transmissions. We do not recomend synthetic transmission fluids.

How much transmission fluid does my transmission take?

The transmission and torque convertor can take anywhere from 9 to 13 quarts of fluid. Most of the fluid is contained in the torque convertor. After installation of the transmission and convertor is complete, pour (4-5) quarts of transmission fluid into the transmission. Then place transmission into neutral, start engine, and quickly add transmission fluid until it reaches the full mark (pan rail level on most applications) on the dipstick. Shift transmission into reverse and let run approximately (3) minutes. Running in reverse (3) minutes will give any contaminants in the transmission, converter, cooler or lines a chance to settle into the transmission pan and not be introduced to the automatic shift control part of the valve body or governor, causing the shift valves to stick. For more details follow link.

Why is the automatic transmission generally perfered over a stick shift transmission?

From a convenience stand point, most high performance automatic transmissions have the ability to be shifted manually or automatically. From an efficiency standpoint, today’s automatic transmissions incorporate a more efficient torque converter that is specifically built for each application. These torque converters have the ability to multiply the engines torque during the stall phase. A clutch on the other hand, simply is along for the ride by connecting the engines power to drive-line. All converters also have a built-in fluid dampening feature. For the higher horsepower applications the automatic transmission and converter combination is more often than not more durable and reliable than the clutch and standard gear box combination. We’ve found when doing conversions from stick to automatic in high performance vehicles that these cars generally drop from a half to three quarters of a second in elapsed time in the quarter mile.