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1968 Camaro T-56 Magnum Transmission - Magnum ForceWe Show What's Involved In Swapping Out A T-56 For The New Magnum Six-Speed. From the October, 2009 issue of Camaro Performers By Steven Rupp Photography by Steven Rupp
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We love the "latest and greatest" as much as the next gearhead, so when Classic Motorsports asked for a volunteer to try swapping a T-56 Magnum in place of a standard T-56, we were on it like a fat kid on a free donut. Our '68 project car is regularly flogged around the track, and while we really liked the current T-56 in the car, the Fifth and Sixth gear ratios weren't optimal. We also liked the idea of the Magnum's purported silky-smooth shifting. Here's our starting point.... Here's our starting point. Under our '68 resided a standard T-56 transmission. Our main concern with the swap was how much the crossmember would have to move. We won't bore you with the removal details, but we simply dropped the exhaust and removed the transmission and clutch assembly. What showed up to our shop was one of the first Magnums to hit the street (PN TUET7477, serial number 77). At that time Classic Motorsports Group was putting their swap kit together and wanted to know what differences there were between the two generations of Tremec six-speeds. The T-56 is a hugely popular, aftermarket transmission, and knowing the differences would greatly help those looking to upgrade their T-56 to the Magnum, or those who were ready to buy a T-56, but are now considering the Magnum. It's nice to know that Classic Motorsports does their homework before shipping orders to customers. While we expected some drama, the overall swap went pretty smoothly and the tweaks required were well within the average gearhead's skill set. After getting the transmission in the car and hitting the road, we were immediately impressed with how smooth the Magnum shifted. It's great when the marketing hype actually pans out to be accurate. With a 0.63 Sixth gear ratio, we're now able to actually use Sixth gear on the freeway without bogging down the engine. Since the install, we've logged a few track events and the new Magnum hasn't missed a beat. Looks like Classic Motorsports and Tremec have hit one out of the park with this new-generation six-speed transmission. Technology In A Box
Since we were swapping out a T-56 for a Magnum, we were able to reuse many of our parts. But what if you're going from a TH350, Muncie, or some other trans, to the new Magnum? Well, Classic Motorsports has made the swap a far less painful event by bundling together complete swap kits. The Basic kit ($3,095) includes the trans, mechanical cable or VSS pigtail, electrical connectors for reverse lockout and light, 31-spline yoke, Hurst shift knob, Energy Suspension trans mount, pilot bearing, and hardware. The Deluxe kit ($3,745) adds a custom Inland Empire Driveline steel driveshaft, crossmember, console emblem, and an optional Hurst offset shifter. The Elite kit ($4,260) adds a nodular iron flywheel, performance clutch assembly, and aluminum bellhousing. They also offer a hydraulic kit ($545), and you can upgrade both the clutch and bellhousing to suit your application.  The T-56 (on the top) is...  The T-56 (on the top) is fairly close to the new Tremec Magnum in terms of dimensions, but there are enough changes to move it out of the "direct bolt-in" category. The new Magnum is longer, the shifter is farther forward by 2.5 inches, and several of the plugs have been changed and moved around.  We've had this QuickTime SFI-certified...  We've had this QuickTime SFI-certified bellhousing (PN RM8020) in the car for some time now and saw no reason to replace it. According to QuickTime, the new bellhousings (same part number) will come already designed to work with the Magnum transmissions, however ours needed a few modifications.  To figure out where we needed...  To figure out where we needed to cut, we loosely bolted the bell to the new Magnum and made some marks using a silver marker.  We're lucky enough to have...  We're lucky enough to have a Bridgeport mill at the shop, but the cuts were still challenging since the QuickTime bellhousing is made from stout H70-grade steel.  Here you can see our completed...  Here you can see our completed modifications to the QuickTime bell. We removed just enough material to clear the new protrusions on the Magnum six-speed.  Before installing the new...  Before installing the new transmission, we decided to upgrade our clutch to a Centerforce Dual-Friction Light Metal (LM) system. We attached the new 13-pound, lightweight flywheel (PN 900142) to the crank using OEM-style bolts and torqued them to spec. According to Centerforce, when combined with their LM pressure plate, the rotating mass is reduced by 16 pounds-and that's just the static weight.  Using a GM 26-spline installation...  Using a GM 26-spline installation tool, we then put the dual-friction disc in place (PN 017010). Centerforce's disc uses a stronger disc hub with their dual-friction disc and organic material on both sides. This drastically increases the PSI factor on the entire assembly and really increases holding strength.  With the disc in place, we...  With the disc in place, we could install the LM pressure plate (PN LM360010). Centerforce's Will Baty explained to Camaro Performers, "The Light Metal Assembly has many advantages over the OE pressure plate. The LM pressure plate is about 5 pounds lighter than the OE pressure version and has over double the clamp load/pressure. The release rate (amount of travel to release the disc) on the LM is faster than the OE as well. The stock hydraulics have enough issues already, so having a quicker release rate is a bonus."  We then transferred the throw-out...  We then transferred the throw-out bearing and slave cylinder from the old T-56 to the new Magnum. Since it had already been used, we didn't need to pre-bleed it.  Next, it was time for the...  Next, it was time for the moment of truth. It turned out that the drama we expected never materialized and the new Magnum simply slid in to place. We did need to enlarge the hole in the trans tunnel to accommodate the shifter now being farther forward. A curved Hurst shift handle from Classic Motorsports compensated for the change in location and actually gave us better positioning than we had before.  Everyone seemed to think the...  Everyone seemed to think the crossmember would have to move an inch-or-so, but that wasn't the case. The new magnum even used the same energy suspension poly mount as our old T-56. except for the minor change in shifter location, and the modification to the bellhousing, I think we can call this transmission a direct fit.  Everyone seemed to think the...  Everyone seemed to think the crossmember would have to move an inch-or-so, but that wasn't the case. The new magnum even used the same energy suspension poly mount as our old T-56. except for the minor change in shifter location, and the modification to the bellhousing, I think we can call this transmission a direct fit.  Although the new Magnum has...  Although the new Magnum has provisions for running a mechanical speedometer, we're using an electronic one. Still, we needed to plug off the hole in the trans for the mechanical parts. Classic Motorsports had this handy plug made just for doing this included in their Magnum VSS kit.  Besides the shifter location,...  Besides the shifter location, the other big dimensional change to the Magnum is that it's quite a bit longer than the older T-56. This meant we needed Inland Empire Driveline to shorten and rebalance our 3.5-inch aluminum driveshaft. To ensure accurate balance, we also gave them the 31-spline 1350 yoke (PN 2-3-6041X, $69) supplied by Classic Motorsports.
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