700-R4 Transmission Upgrades - Chevy Slushbox Performance Tricks

Automatic transmissions were nicknamed slushboxes for a reason. For the most part, automatics are designed to shift for maximum comfort with little or no performance considerations. This is great for the grocery getter, but leaves driving enthusiasts wanting more.

This is where the aftermarket has made a definite improvement. A number of companies have designed kits that improve the way automatics shift, allowing them to be shifted at a higher rpm for a firmer feel and better acceleration. The popular TH700-R4 has been used in thousands of vehicles (both from the manufacturer and in custom applications) and is a prime candidate for shift improvements.

Transpak Installation
Here's a shot of the parts included in the 700-R4 Transpak. Depending on your needs, the kit is actually two kits in one: one for Heavy Duty/towing (great for GM trucks with the 700-R4) and another for street performance. The instructions tell you which components are used to achieve the performance you need.

Transpak Installation Here's a shot of the parts included in the 700-R4 Transpak. Dependi

To improve the shifting characteristics of the 700-R4 gearbox on our third-generation Camaro, we called upon B&M Racing & Performance Products. B&M suggested a Transpak kit for the car. In addition, B&M touted the fact that its easily installed transmission oil coolers will greatly increase the life of the 700-R4. B&M is also famous for its line of bolt-in shifter upgrades. Because the factory Camaro shifter is fairly sloppy and lacks a gear indicator, we decided to completely revamp the shifts of the car from driver's hand to the pavement. Remember that all of these upgrades can be made to any vehicle equipped with a 700-R4, so your Tri-five, Nova, Monte Carlo, or Chevelle will see nearly the same improvements as we did on our F-body. Installing B&M's Transpak kit is fairly straightforward, but isn't quite as simple as, say, swapping an intake. The inner workings of an automatic gearbox are complex, with valves, springs, and check balls that require exact placement. What we're saying here is that the instructions should be fully read beforehand and then closely followed. Having seen the kit installed we'd also recommend double-checking everything before putting it all back together.

In the tools department, hand tools were about all that's required. B&M includes the necessary drill bits. One thing that will make the installation much easier is a lift. Without a lift, you will want to get the car on a level surface and raise it as high as your jackstands will go. This allows you room to work comfortably under the car.

When it came time to install the Megashifter and SuperCooler the process was much easier. In addition to the aforementioned basic hand tools, you will need a 9/32-inch drill bit for the Megashifter mounting screws. To see the entire process, follow along with the remainder of this story.

Transmission fluid can reach in excess of 200 degrees. Allow the transmission to cool sufficiently before beginning this project. Then unbolt and remove the pan...
Transmission fluid can reach in excess of 200 degrees. Allow the transmission to cool suff
...and filter.
Next unplug the electronics and begin unbolting the valve body.

Exercise caution when removing the valve body, as it contains more fluid.
Also remove the 1-2 accumulator housing.
All parts should be set aside and cleaned with a solvent. Dirt and debris can harm the transmission.
All parts should be set aside and cleaned with a solvent. Dirt and debris can harm the tra

A roll pin is used to retain the line bias valve.
The line bias valve spring is replaced with a solid blocker rod.
On the MTV upshift valve, the spring isn't replaced; it's simply removed and the valve is re-installed without it.
On the MTV upshift valve, the spring isn't replaced; it's simply removed and the valve is

Enlarging the holes in the valve body separator plate is easy, but be sure to follow the very detailed instructions and diagrams that are included. This allows increases in the line pressure and affects the shift characteristics.
Enlarging the holes in the valve body separator plate is easy, but be sure to follow the v
Per the instructions, the factory pressure regulator spring is set aside and the blue spring included in the kit was installed in its place.
Per the instructions, the factory pressure regulator spring is set aside and the blue spri
Before assembling the accumulator, the separator plate was prepared. Toy Shop uses transmission grease and spreads it on the gaskets to hold them to the plate. Then the grease is used to hold the check balls in place.
Before assembling the accumulator, the separator plate was prepared. Toy Shop uses transmi

The accumulator was assembled per the instructions included with the B&M kit and installed over the separator plate. Notice that two of the valve body bolts were installed through the plate to ensure everything was aligned properly.
The accumulator was assembled per the instructions included with the B&M kit and installed
With the accumulator holding the plate in place, the bolts were removed and the valve body was re-installed with its check balls installed per instructions.
With the accumulator holding the plate in place, the bolts were removed and the valve body
After reconnecting the wiring, the new B&M transmission filter was installed...

...and the cover re-installed.
Megashifter Installation
The Megashifter from B&M is available for some application-specific installations or it is available in a universal kit.
Megashifter Installation The Megashifter from B&M is available for some application-speci
For our '86 Z28, B&M offers PN 80692, which is designed to fit '82-92 Camaros with little modification.
For our '86 Z28, B&M offers PN 80692, which is designed to fit '82-92 Camaros with little

Since Toy Shop Transmissions had just finished up with the internal transmission modifications, the car was still in the air on the lift. This made it easy to begin with the cable and shift arm installation. The old linkage was removed and the new control lever was installed.
Since Toy Shop Transmissions had just finished up with the internal transmission modificat
A bracket is included to hold the new shifter cable in place. Special care should be paid to the instructions, which call for spacers between the bracket and the transmission. These spacers allow the bracket to fit without modification to the transmission pan.
A bracket is included to hold the new shifter cable in place. Special care should be paid
Moving to the inside of the car, the shifter ball was removed...

...and the cover plate unfastened and set aside.
With the shifter exposed, the cable was disconnected and pulled through the floor.
Another cable is attached to the shifter mechanism. It controls the steering wheel lock and only allows the lock to engage when the selector is in the "Park" position and the key is in the "Lock" position. It must also be removed from the shifter before continuing. More instructions on this later.
Another cable is attached to the shifter mechanism. It controls the steering wheel lock an

The last thing to remove before unbolting the shifter is the neutral safety and reverse switch. This unit can be unplugged, and after unbolting the shifter the entire assembly can be pulled from the vehicle.
The last thing to remove before unbolting the shifter is the neutral safety and reverse sw
The new neutral safety and reverse switches are included with the B&M shifter. These must be installed on the shifter before installation and will require a slight modification to the wiring. For our 700-R4, which features an additional gear as opposed to a non-overdrive transmission, a restrictor bolt must be removed to allow the selector to move into overdrive.
The new neutral safety and reverse switches are included with the B&M shifter. These must
There are detailed instructions for proper mounting of the shifter. Our Camaro required using two existing mounting holes and drilling two new holes. Once ready, the shifter was set in and firmly secured in place.
There are detailed instructions for proper mounting of the shifter. Our Camaro required us

After the shifter was in place, the steering wheel lock cable was secured and stashed out of the way. To keep the cable in the park position we used a small zip tie and wrapped it around the cable, then used a large zip tie and threaded it through the small tie and the end of the cable. This worked well to hold the cable all the way in. B&M includes a warning that due to the fact that the cable is now always in the "Park" position, the steering wheel can be locked whenever the key is turned to lock (this means that if you turn the key to lock while moving, the steering wheel will lock up).
After the shifter was in place, the steering wheel lock cable was secured and stashed out
The top end installation was finished up by installing the shifter cable...
...and wiring the switches (follow the instructions carefully).

A template is included to modify the factory trim plate.
After marking the pattern, an air cut-off was used to cut the opening.
Before installing the shifter trim plate, the proper gear indicator window (three- or four-speed) was installed. The trim plate bolts to the factory trim cover and everything uses the existing holes.
Before installing the shifter trim plate, the proper gear indicator window (three- or four

A rubber boot is included to keep debris from falling into the center console.
After finishing the topside installation, we returned to the underside of the car and routed the cable and attached it to the bracket. Then the cable was adjusted per instructions and secured to the shift arm.
After finishing the topside installation, we returned to the underside of the car and rout
Supercooler Install
The B&M SuperCooler is a really simple installation, though most applications will probably be a little easier than on our Camaro due to the radiator and air conditioning configuration. That said, it still only took about half an hour to install.
Supercooler Install The B&M SuperCooler is a really simple installation, though most appl

To install the SuperCooler it was necessary to loosen the radiator and tip it towards the engine. This allowed the SuperCooler to be slipped in between the front-end supports and the radiator. We installed the hoses before setting the cooler in place because the tight space would have made it very hard to attach the hoses and clamps once installed.
To install the SuperCooler it was necessary to loosen the radiator and tip it towards the
Once in place, the hoses were routed to the passenger side of the engine compartment. This photo shows the supports that required our radiator to be moved (the cooler almost fit between the braces, but didn't quite make it).
Once in place, the hoses were routed to the passenger side of the engine compartment. This
The hose connections are simple. The SuperCooler works in addition to (not in place of) the factory transmission cooling system.
The hose connections are simple. The SuperCooler works in addition to (not in place of) th

We finished off the project by filling the transmission with B&M's Trick Shift automatic transmission fluid.
We finished off the project by filling the transmission with B&M's Trick Shift automatic t