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ATK Performance Transmissions

Need a transmission that is powerful enough to support your new High Performance Engine? Look no further than the below selection of our HP Transmissions. Give us a call and we can recommend the perfect fit for your ride!

All of our transmissions are built for your application. In order to best serve you we will need the following information: year, make, model, gear ratio, tire size, vehicle weight and engine/cam specs. By getting this information we can calibrate the transmission to shift where it should and make sure your speedometer is accurate.
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ATK HP400HD Heavy Duty TH400 Transmission
Our Price (USD): $1,445.00

Our heavy duty 400 features heavy duty clutches and bands, valve body and lube modifications to provide a durable transmission ideal for light trucks and passenger cars. Comes with our heavy duty 1500-1700 stall converter. This unit is rated to 400HP/450 lbs of TQ and is available in both Chevy and Buick, Olds, Pontiac and Cadillac applications.
Heavy Duty TH-350 Transmission
ATK HP350HD Heavy Duty TH-350 Transmission
Our Price (USD): $1,450.00

Our heavy duty 350 is a perfect replacement trans for those seeking a stronger and better performing trans but don't need nor want a street/strip type trans. This is a great transmission for engine applications up to 325hp. Trans is built with heavy duty clutch packs, shift improvement, and durability modifications. Includes our heavy duty torque converter with 1600-1800 stall speed. A lot of trans for a little money.
ATK HP400SS Street/Strip TH400 Transmission
Our Price (USD): $1,590.00

Our heavy duty 400 with higher capacity clutch packs, Kevlar band, high capacity 34 element sprag race and semi-automatic valve body, which allows you to select gears manually, or leave it in drive for full automatic shifting. This trans includes our 2000-2200 stall converter and is a great choice for the weekend warrior with up to 600 horsepower and a heavy foot.
ATK HP350SS Street/Strip TH350 Transmission
Our Price (USD): $1,615.00

Our heavy duty trans with a lot more performance built in, including semi-automatic shifting which allows you to manually upshift or downshift or let the trans shift automatically. This transmission is rated for engines with up to 450hp. The trans also features a special intermediate sprag race and high rpm governor. A great trans for hot rodding around and occasional racing. Includes our 2000-2200 stall converter.
ATK HPC6HD Heavy Duty C6 Transmission
Our Price (USD): $1,630.00

This is our Heavy Duty C-6 transmission built for light trucks and passenger cars requiring a stronger than stock transmission for light towing or everyday driving requirements. Clutch pack capacity is increased and valve body is modified for improved shifts and lube transfer. Transmission includes our Torque Max torque converter in stall speeds up to 1800 rpm. Available for most Ford engines and applications.

4x4 option is an additional $150.00 / Small block option is an additional $125.00
ATK HPC6SS Street/Strip C6 Transmission
Our Price (USD): $1,765.00

This is our Street/Strip version of the C-6 built for higher output applications up to 450HP. This trans features improved servo design, modified valve body, increased clutch capacity and lube mods to insure trouble free high performance fun . Includes our Torque Max torque converter in stall speeds up to 2400 rpm. Available for most Ford engines and applications.

4x4 option add $150.00 / Small block option add $125.00
ATK HP350SX Extreme Duty TH350 Transmission
Our Price (USD): $1,895.00

This is our strongest 350 capable of horsepower and torque in excess of 600Lbs If you want the ratios and size of the 350 but the strength and capacity of a 400 then this is the perfect choice for you. This transmission features a custom machined High clutch drum with 36 element intermediate sprag, 5 high performance clutches in both the forward and direct clutch pack, extra wide hi performance low reverse sprag with wider outer race, and the choice of either a semi automatic or full manual hi performance valve body. In addition to these features this model includes our "Torque Max" torque converter with stall speed up to 2500 rpm, a hardened drive hub with anti balloon plate and hardened turbine hub.
ATK HP700R4HD Heavy Duty 700R4 Transmission
Our Price (USD): $1,905.00

Our heavy duty replacement model for vehicles originally equipped with the 700 or those wanting to upgrade to an overdrive with a maximum of 325 horsepower. This model features over 25 upgrades and modification to improve durability and performance and comes with our heavy duty lock-up torque converter with stall speed up to 1800 rpm.
ATK HP400SX Extreme Duty TH400 Transmission
Our Price (USD): $1,945.00

This is the trans of choice for high output engines up to 850HP. The 400Sx has a modified pump for higher operating pressure, 300M input shaft and re-broached forward clutch drum with larger spline contact area, 300M input clutch hub, semi metallic frictions, Kevlar lined front band with reinforced anchor points, extra direct clutch, 34 element intermediate sprag, improved design low reverse sprag, upgraded center support and customized valve body and governor with both automatic or semi automatic shift selection. The transmission is performance clearanced during the build including clutch packs and gear train as well as final endplay. Low drum is machined and a wider band used, low/second accumulator is modified for quicker band release. All external hardware is cad plated and the pan is a new, heavy steel part to resist leakage.
ATK HP700RDHD4X4 700R4 Transmission
Our Price (USD): $2,045.00

Our heavy duty replacement trans for 4 wheel drive pick-ups and Blazers is packed with additional upgrades to handle up to 450 horsepower and the additional strain of oversized tires and off-road use. This trans also includes our 4x4 torque converter with stall speed modified for off-road and towing use. This transmission features the factory ”K” case with provision for bolt on aluminum dust cover and block supports and is designed as a direct replacement for GM four wheel drive trucks originally equipped with a 700R4 transmission.