When it comes to blending the best of modern technology with the incomparable style of vintage sheet metal, it’s hard to beat a first-generation Camaro with a late-model powertrain – especially when the gear-changing duties are handled manually.

Sure, an LS-powered vintage Bowtie backed by a strong 4L60 or 4L85 automatic overdrive is a great way to soak up the miles without effort, but for those who prefer the more engaging experience and greater feeling of control that comes with shifting for themselves, there are plenty of options to the old-school Muncie four-speed.

The TREMEC Solution

Those options have a common denominator, however: TREMEC. The company’s venerable five- and six-speed internal-rail manual transmissions have been behind factory Camaro small-block engines since the mid-Eighties, delivering a great balance of performance and efficiency. In an early Camaro, those admirable qualities are enhanced immensely by the vast improvement in drivability.

Hey, we love crunching the gears on an old Rock Crusher as much as the next guy, but the smooth shifting action, quiet performance and low highway cruising speed for the engine makes an old, noisy and high-winding four-speed seem about as practical as ditching an HEI for a set of used points.

With a high-gear overdrive ratio of about 0.64, a five- or six-speed will lower the cruising rpm at 70 mph by about 1,200 rpm in a Camaro with a 3.73-geared rear axle compared to a typical M-22 Muncie four-speed. That means a reduction from about 3,300 rpm to about 2,100 rpm, which improves fuel economy, cuts interior noise and reduces engine wear.

While five- and six-speed conversions in first-generation Camaros – and other classic Chevys – are nothing new, they’re becoming increasingly popular, thanks to comprehensive conversion kits from companies such as Hurst Drivelines and American Powertrain. We’ll discuss those kits in a moment, as well as our own Camaro project that will match a TREMEC T-56 Magnum to a 700-hp LSX-based engine, for the ultimate in Pro Touring performance.

The “Red Devil” 1969 Camaro that Pro Touring pioneer Mark Stielow built and drove to win the OPTIMA Ultimate Street Car Challenge a couple of years ago exemplifies this growing trend.

Apart from its modern rubber and wheels, the blood-red classic Camaro looked stock on the outside, but packed a modified LS9 crate engine that was backed by a TREMEC six-speed. It out-hustled cars with greater power-to-weight ratios, while also delivering exemplary street manners.

“Any good vintage car that you want to use as a driver really needs an overdrive transmission for total enjoyment,” said Stielow. “It’s much more pleasurable on the road and you’ll really get the best of both worlds – a classic car with a modern driving experience.” Stielow settled on Tremec six-speeds after experimenting with other five- and six-speed transmissions over the years.

His latest project – a ’67 Camaro – will be powered by another LS/TREMEC combination. “I started using overdrive manuals in 1989, but used my first T-56 in 1999 and haven’t looked back,” Stielow tells us. “In my opinion, the TREMEC six-speed is the best all-around transmission.”

Review // Past & Present

Let’s take a moment to review the current state of six-speeds: The TREMEC TR6060 six-speed manual transmission that backs the 580-hp LSA engine in the Gen-5 Camaro ZL1 has its roots in the T-5 five-speed transmissions that debuted in, of all things, the 1980 AMC Spirit. It was developed by Borg-Warner Automotive and by 1983, it found its way into Mustangs and Camaros.

The prevalence of 5.0-liter Mustangs has forever linked the transmission to Ford’s pony car, but if you bought a V-8 Camaro with a manual from the mid-Eighties to early-Nineties, the T-5 was the trans du jour, as well.

The T-56 six-speed was introduced in the Dodge Viper in 1992 and the Camaro received a version in 1993, with the launch of the fourth generation Camaro (Corvettes used a ZF-sourced six-speed from 1989 to 1996). There were several production versions of the T-56 and they even differed between LT1-engine applications in four-generation F-bodies and the later LS1-powered cars.

The T-56 is no longer used in OEM applications, as it was supplanted by the TR6060, but its production carries on as the aftermarket-only T-56 Magnum. It is basically a T-56 case stuffed with the heavier-duty guts of the TR6060. Likewise, performance-oriented versions of the TREMEC five-speed, including the TKO transmission, are also in production for aftermarket applications.

In the late nineties, TREMEC purchased Borg-Warner’s manual transmission business, instantly making the Borg-Warner five- and six-speeds TREMEC transmissions.

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The Magnum transmission isn’t interchangeable with a used T-56 as a swap candidate. For one thing, the tail shaft (left) is about three inches longer than the T-56, although the shifter position is farther forward. That’s one of the reasons the more retro-fit-friendly Magnum was developed in the first place. The cases of the T-56 and TR6060/T-56 Magnum aftermarket transmission are similar at a glance, but the Magnum case (front) is stronger in key areas, both outside and inside. All are made from die-cast aluminum, but the thicker Magnum case and larger gear sets inside add approximately 20 pounds to an assembled transmission vs. a comparable T-56.

Five-speed vs. Six-speed

Assuming you’re buying all-new components, the logical nod to your transmission investment would be the six-speed and, more specifically, the T-56 Magnum, but the TREMEC TKO five-speed offers a number of advantages:

 

• It is compatible with most OEM bell housings – including original-style four-speed housings – and fits with comparatively minor floor/chassis modifications
• Lower cost – the transmission is less expensive than the T-56 Magnum, although the installation kits are comparably priced
• The TKO 600 is rated for 600 lb.-ft. of torque in its stock configuration and can be enhanced to support more than 900 lb.-ft.
• It offers dual speedometer outputs (mechanical or electronic) for easy wiring and compatibility with most mechanical linkages

In its stock, bolt-in configuration, the TKO is a good, economical choice for vehicles with powertrains cranking out less than 650 lb.-ft. and anticipated shifting limits below about 6,500 rpm. We’re talking Gen I and Gen II small-blocks, here, for the most part.

When the performance in your project ratchets up to the heavy-breathing LS level, with high-rpm horsepower and shifting, it’s time to consider the T-56 Magnum six-speed. That’s when we contacted Nate Tovey of TREMEC for the inside scoop. It’s rated for 700 lb.-ft. of torque and a 7,000-rpm shift capability. Though the Magnum is rated for 700 ft-lbs of torque, Tovey says “Don’t really think in terms of ‘numbers.’ If you know how to treat your transmissions, these will support far greater torque than they are rated for.” He adds, though, that abuse is just dumb. “Think of the shock loads you put on the drivetrain with, say, clutchless shifting. Besides, when you do that, the synchros will wear out.” It also offers a pair of overdrive gears – 0.80 (fifth gear) and 0.63 (sixth gear) – vs. the TKO’s 0.64 fifth gear, which enhances the cruising speed options around town. Also, the gear ratio spread is better matched to a higher-power engine with the six-speed, for a greater overall feeling of performance.

If there’s a compromise with the selection of a T-56 Magnum-based swap, it’s a more complicated installation in an older vehicle, but not prohibitively so. We’re going with this transmission in our Camaro project, because the advantages far outweigh the extra fab time required to fit it in the car.

We should mention, that if you’re contemplating picking up a used T-56, do your research and know exactly where it came from, i.e. an LT1 Camaro, LS1 Trans Am, etc. The exact model will determine some of the conversion components required for the swap. This story focuses on the T-56 Magnum as the six-speed of choice.

Oh, and before you ask, we spoke to Matt Graves of American Powertrain about the TREMEC fitment issues. Graves stated,”By using a TREMEC aftermarket transmission such a Magnum or TKO it allows us to easily adapt the offset shifter to get the correct placement.” In short, the T-56 out of your buddy’s blown-up fourth-generation Z28 isn’t a direct fit for the Magnum-based conversion kits described below.

The production T-56’s tail shaft is about three inches shorter than the T-56 Magnum and the shifter position isn’t the same, either. Also, the T-56 simply isn’t as strong and it doesn’t offer some of the swap-friendly features of the aftermarket-intended Magnum. Sure, you could make the production T-56 work, but the project won’t be as easy, so our advice would be to spring for the T-56 Magnum. You’ll be better off in the long run.

Conversion Basics // What You Need To Know

Marrying a TKO or T-56 Magnum with a first-gen Camaro (or other older car) requires a few unique parts and likely some floor pan modifications. The swap kits, which we’ll detail shortly, typically include the unique parts, but it’s definitely up to the installer to trim the car’s sheet metal where necessary. Also, it’s easier and less costly to swap the trans into a car that was originally equipped with a manual transmission, but kits are available to convert previously automatic-equipped models.

Let’s start with the transmission itself. Whether it’s a TKO or T-56 Magnum, it’s going to be longer than the average Muncie four-speed. The TKO is a hair more than 24 inches long, while the T-56 Magnum stretches about 28 inches, stem to stern (bell housings not included). The average M-22 Muncie is roughly 21.5 inches long, without a bell house. Those differences in length vary with the bell house, but the bottom line is a longer transmission is going to require a shorter driveshaft (with a 26-spline slip yoke).

Also, using a TKO or T-56 Magnum will alter the position of the shifter. The conversion kits have the parts or complete shifter assemblies to accommodate this, keeping the shifter in the stock position in the console, but if you do it yourself you’ll have to modify a shifter handle to move the stick up a couple of inches.

One of the advantages of using a TKO transmission is that it will tuck up into the trans tunnel of a first-generation Camaro without tunnel or floor pan modifications, as long as you use an offset shifter, such as the Hurst Blackjack shifter that’s an option with Hurst Driveline’s kit. Otherwise, the stock TREMEC TKO shifter will cause a bit of interference and require a little sheet metal trimming.

Using the T-56 Magnum – or other T-56 models – will require tunnel surgery to make room for the shifter. Even if you use an offset shifter and/or slide the center console rearward, clearance for the shifter mechanism itself must be made about four inches rearward of the original shifter hole in a manual-trans first-gen car. And by clearance, we mean you have to cut a hole in the floor.

Additional components of the swap include:

• A rear crossmember to support the tail of the transmission
• A speedometer converter, either mechanical or electronic, depending on the transmission
• Reverse light adapter
• Pilot bearing

You’ll have to address issues regarding the flywheel and the possible need of an adapter plate between the bell housing and the transmission. You can also upgrade to a hydraulic clutch, for a lighter, more modern feel and you’ll also need a 26-spline clutch disc.

Removing your Camaro’s existing transmission and swapping in the new trans is entirely possible with the engine still in the car, but it makes the job harder and there’s not as much room to maneuver when bolting up the transmission. If you can do it, remove the engine or, at the very least, tilt the engine rearward for greater clearance. This will likely require removing the distributor cap or the distributor itself to prevent it from hitting the firewall. Then again, if you’re going to the trouble of tilting the engine and removing the distributor, you might as well simply pull the engine – if you have the capability in your garage.

Swap Kits // Availability Is Just Around The Corner

Among the transmission swap kits on the market, Hurst Drivelines and American Powertain both offer systems for TKO and T-56 Magnum transmissions that are tailored for first-generation Camaros. Both companies’ kits are comprehensive and include detailed instructions. Hurst Drivelines offers three conversion kits – essentially; basic, more complete, and everything-but-the-kitchen-sink levels of equipment.

Hurst’s basic kit includes the transmission, a speedometer cable/converter – or VSS speed sensor and related electrical connectors with the T-56 Magnum – pilot bearing, reverse light switch connector, slip yoke and transmission mount, meaning you’ll have to fabricate the crossmember and scrounge a new driveshaft. If you select their mid-level “Deluxe” kit, the crossmember and driveshaft are included, along with an appropriately delineated shift knob and console shift pattern graphic.

The “Elite” kit from Hurst includes all the items in the Deluxe kit and adds a bell housing, clutch kit, clutch fork, flywheel and shifter stick. It’s the kit for those converting an automatic car to a manual, or for the builder who wants all-new parts from stem to stern. And if you feel that the swap is somewhere above your comfort and/or skill level, Hurst’s website has a list of authorized installation centers in the United States and Canada.

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Here’s a look inside Mark Stielow’s ’67 Camaro, showing the six-speed shifter rising out of the trans tunnel, basically in the position of the old four-speed. The trans swaps for these cars have never been easier and the results greatly enhance drivability. Several swap kits on the market are designed for Camaros originally equipped with an automatic transmission. There’s a bit more to the conversion, but again, the kits make it mostly a straightforward bolt-in – including putting the shifter in stock position in the console.

Over at American Powertrain, we again touched based with Matt Graves. Their installation kits are comparable to Hurt’s Deluxe kit, with the crossmember and driveshaft, along with a shifter mechanism, shift handle and knob. Graves revealed, “Our X-Factor crossmember is low profile and lightweight. It has adequate clearance for dual, 3-inch exhaust as well.”

Also, at a price of around $900, the kit doesn’t include the transmission, but American Powertrain will add either a wide-ratio or close-ratio T-56 to your shipping box for about another $2,900. That puts the six-speed transmission and the parts required to install it in your driveway for about $3,800. You can expect to make a similar investment for a Hurst kit or other conversion systems. Generally speaking, going with a TKO 600 five-speed transmission will lop about $500 off the initial investment, although it will require comparable installation time.

If it was us – and for our Camaro project, it is – we’d spend the few extra dollars for the six-speed setup. The T-56 Magnum is rated for more torque, the gearing delivers a greater performance feel and, without a doubt, there’s a more technologically advanced vibe with a vintage car that packs a six-speed. With the kits from Hurst Driveline and American Powertrain, such a swap has never been easier or more cost effective.

Leave the rock crushing to the guys at the quarry and hit the highway with a modern manual transmission!

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Here at Chevy Hardcore, we’re getting ready for our own six-speed swap in our ’69 Camaro project car (originally an automatic car). Our complete kit from American Powertrain (PN, PFGM-30001) included a race balanced driveshaft with solid U-joints, X-factor crossmember, transmission mount, pilot bearing and reverse light harness. It also features a speedometer conversion, shifter knob, console shift pattern plate, and modular reverse lock-out with the light harness. Of course, all of the necessary hardware instructions, warranty and 24-hour support are also thrown in to make this one very appealing kit. We’ll be hooking it to a powerful LS engine to turn our vintage F-Car into a contemporary cruiser. Stayed tuned for more on this exciting project.