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1973 Chevy Camaro - Transmission Swap - 5 Deep
Modern-Day Fun In An Old-School Package
Henry De Los Santos
Oct 1, 2008
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1973 Chevy Camaro - Transmission Swap - 5 Deep
Use only GM Synchromesh (PN 12345349) or Pennzoil Synchromesh. It takes 5.28 pints of synchromesh to fill up the transmissionEvery trans includes the wiring for a neutral safety switchAll kits come with a special pigtail connector that clips directly onto the reverse-light switch connectorAll kits come with a custom-built mechanical speedometer cable with integrated adapter and gearElectronic VSS kits are also available for aftermarket gaugesThe Tremec TKO-600 is rated to handle up to 600 lb-ft
Prior to disassembly, Jim Goodlad, known as "GM Jim" throughout the Internet, is responsible for R&D and new product design. He started by checking out the driveshaft angle with the suspension unloaded, which showed 20 degrees. To check the pinion angle, he then rotated the driveshaft 90 degrees and found it at 16.5 degrees, giving a total of 3.5 degrees working angle. While this isn't necessary, it's a good practice to follow because it provides a baseline to ensure that the new setup will drive smoothly with no vibration.
Using a trans jack for support, we disconnected the exhaust and removed the starter. Since our transmission lines were pretty beat up, rather than trying to salvage them, we went ahead and cut them. Just make sure to have a pan handy underneath or else you're in for a mess. From there, it was only a matter of removing the bellhousing bolts from the motor (three on each side) and the tranny was out. The passenger side can be a little more challenging due to header and cooler line clearance. The scary part-every bolt was only finger-tight.
With the flywheel removed, Goodlad used an abrasive wheel to clean up the back of the block. Then, using a file, he checked the block for any imperfections that could prevent the new bellhousing from sitting flush. Once everything checked out, he installed the needle roller pilot bearing with a flat drift. He emphasized the importance of using a flush tool rather than the end of a socket; any bearing distortion could make it hard to install the transmission and even cause premature bearing failure.
The Elite kit comes with a nodular iron flywheel and hardware, but we opted for the SFI-approved billet steel upgrade for an additional $150. If you're using the supplied ARP moly lube, you'll want to torque the flywheel bolts to 70 ft-lb; otherwise it's 90 ft-lb with conventional oil.
The Elite kit also comes with a heavy-duty clutch kit rated at 425 hp and includes a disc, a pressure plate, a throwout bearing, an alignment tool, and hardware. Since we upgraded to the billet flywheel and have a motor making a significant amount of power waiting to be dropped in, we went with the Strip Comp rated at 700 hp for $345 more. Once it was secured in place, Goodlad torqued the 3/8-inch bolts to 35 ft-lb.
You can skip this step if you're using the mechanical linkage. Because we were using a hydraulic throwout bearing setup, prior to placing the hydraulic bearing the antirotation stud was installed onto the input shaft retainer collar.
Included in the kit is an aluminum reproduction version of GM's 621 bellhousing. It is precision-built for a perfect fit, machined within 0.005 runout, and comes with the ball stud, a factory inspection cover, and hardware.
The self-adjusting hydraulic throwout bearing assembly comes complete as one unit with custom braided lines and slides right over the input shaft. The two braided lines that attach to the bearing are a bleeder line up top and a lower line that connects to the compact master cylinder.
If you don't have a factory console (or are converting a factory automatic to stick), the stock Tremec shifter mechanism centered in your floorboard is more than adequate. If you're looking for a true bolt-on shifter from a four-speed conversion that'll position the shifter stub in the factory location without cutting or modifying the trans tunnel, then the optional offset shifter is the way to go. It'll cost an additional $295, but that's a bargain if you don't want to cut or are planning to eventually install the factory console.
Because we were starting with an automatic car, the tranny had to be mocked up from underneath to see where the shifter hole needed to be cut. Once it was positioned, it was only a matter of hitting it with a punch, then using a jigsaw.
The CMG crossmember is mandrel-bent, 0.120-inch-wall, 1020 carbon-steel tubing with CNC-cut flanges, and features precision TIG welding. Translation: It offers a perfect fit with serious rigidity. All kits come with an Energy Suspension polyurethane mount for longevity. If your body mounts are crushed or if you have floor sag, you will have to play with it a little to get the crossmember to fit properly. We had both issues, but it still went together with minimal effort.
Each Deluxe and Elite package comes with a driveshaft. For first- and second-gen Camaros, CMG offers complete bolt-in pieces with Spicer U-joints and a C6 slip-yoke, rated up to 500 hp. If you're generating more power (or whenever the application requires a driveshaft that's 50 inches or longer), CMG recommends stepping up to the 3.5-inch-diameter steel or an aluminum driveshaft. Larger 1350 U-joints are also available for higher horsepower applications.
Shown here is the hydraulic throwout bearing's master cylinder and linkage, which slides through the CMG billet aluminum firewall mount bracket (arrow). The bracket alone is a vital custom-made CMG piece that provides support for the thin firewall as well as proper geometry for the pushrod and the way it's angled; it is designed to clear boosters.
For the remote mount reservoir kit, CMG provides an ample amount of line for placement wherever it works best for your particular application. During our installation, we made a custom mount from a 31/4-inch strip of 1/8-inch-thick metal to place it next to the brake master cylinder.
Whether you need a clutch pedal for the hydraulic bearing or the complete linkage for a mechanical setup with the Z-bar, CMG offers a total package deal as an upgrade.
Our carpet is pretty ragged, and until we replace it, we're waiting to mount the shifter boot and trim. Nevertheless, the shifter has that classic appeal, and the ball on top of the retro handle says it all.
There you have it, from start to finish. The CMG Elite kit is a complete, turnkey package that's constucted from a serious amount of R&D. Then again, when you have a bunch of gearheads who wrench on their own cars as test vehicles, it really shouldn't come as a surprise when their system delivers what they promise.
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