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If you have any questions feel free to give us a call 570-578-5686

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These Converters feature hand brazed impellers, heavy duty stators, Torrington bearings (not washers), a specially machined surface for additional cooling.

Performance Extreme-Duty sprag assemblies, special high heat, high friction carbon composite converter lockup clutch lining, and a 4140 chrome molly steel hub.

These units are built tough and to your custom needs.

In addition, these converters feature a Billet Steel cover which allows for a larger converter lockup clutch area.

They are also available with an optional mechanical diode instead of the one-way sprag for use with very large NOS shots and/or very heavy performance vehicles such as large trucks.

These are not off the shelf units!

Our 9.5 inch Pro Race Series converters are available in 1.69, 2.1 and 2.5 STR in stalls from 2800 to 4000 RPM stall.

To help you choose, here is some additional information about stall torque ratio. Stall torque ratio is the multiplier for torque for a short time when the car is launching. Higher STR will give a much higher torque multiplication for a very short time right at launch, but with an overall cost in efficiency at the top end. In other words, higher STR will increase your 60 ft times, but it may be at the expense of MPH at the top end. Lower STR, while it will not deliver the punch at the bottom like a higher STR, will give torque multiplication for a longer period of time and may allow you to place more power to the ground with less spinning. Additionally, the over all efficiency is much better. Where a 2.5 STR might be only 90 percent efficient above rated stall, a 1.69 would be 96 percent efficient above rated stall (both these numbers based on converter not locked). This means you put more power to the ground throughout the run down the track.

Each person has different needs and goals, which is why we offer multiple STR.

These are, hands down, the strongest, best torque converters on the market today.

All our converters are warranted for 1 year.

All prices include shipping inside mainland United States. No core is required!

The more we know about your needs, the better we can match you with the right converter. You must CONTACT US so we can make sure your converter is properly built for you.

The information we need is:
Engines size
Dyno (or estimated) horse power
Actual torque
Vehicle weight
Rear end ratio.

Each customer has different needs and goals, which is why we offer multiple STR options. All our converters are warranted for 1 year from date of receipt of the converter at your home. Warranty and liabilities are limited to what is stated on our warranty page.

These converters come in 2800 to 5000 stall.

You can get any stall inside this range (within 100 rpm) depending on the parts combination necessary to get the requested STR and stall speed.

Prices include shipping to anywhere in the mainland USA. Please call us at 570-578-5686.

All Pro Race Plus and Pro Race Magnum Converters have a Billet Cover and Large Lockup Clutch

Call to order these converters at

  Converter Only With Transmission
700R4, 4L60E & 200 4R
Pro Race Plus $945 $850
Pro Race Magnum (w/diode) $1195 $1100
4L65E LS-1
Pro Race Plus $945 $850
Pro Race Magnum (w/diode) $1245 $1150
Pro Race Plus $995 $900
Pro Race Magnum (w/diode) $1295 $1200
Pro Race Plus $995 $900
Pro Race Magnum (w/diode) $1295 $1200