You’ve most likely heard the colloquialism “big things come in small packages.” That, however, is not typically the case when it comes to all things automotive. In true musclecar fashion, bigger is almost always better—unless you’re a Mustang owner, in which case we pity you (unless it’s LS swapped). One exception to this rule, however, is typically in the transmission department. While the 4L80-E is the larger, and more often than not, stronger transmission when compared to the 4L60-E, the physical restrictions of fitting it where it wasn’t originally intended to be can be a real challenge, since most transmission tunnels with have to be modified to fit. 

Enter Chevrolet Performance’s new SuperMatic 4L75-E transmission. This four-speed box features the compact housing of the 4L60 and 70 with the rugged power handling capabilities of the 4L80-E. In other words, its a lot like an LSX 454; big-block cubes in a small-block package.

Chevrolet invited us out to their newly revamped Global Propulsion Systems center in Pontiac, Michigan to steal a quick sneak peak at the latest transmission before it hit the show room floor at SEMA this week. And, not wanting to be impolite (as well as peeing ourselves a little at the opportunity), we politely obliged.

What we found when we arrived in Michigan was a feat in modern engineering and packaging. We sat down with Development Engineer for Chevrolet Performance’s Powertrain Performance Division, Rusty Sampsel to ask him a few questions about just what exactly was updated in the new transmission.

“This is still the ‘old school’ four-speed but it’s still really popular and for good reason,” Sampsel said. “You get the best of both worlds; it retains the overdrive—which everyone wants—but keeps it in a relatively compact package that can still fit easily in most vehicles without serious floorpan modifications.”

He continued, “Hot rodders over the years have really exposed any of the original 4L60’s weak links, so we deicide to try to build a bullet-proof version that could handle a lot more but retain its compact packaging—this is what we came up with.”

The tranmission comes with a 650 lb-ft torque capacity, making it just as capable as its big brother, if not more so in some cases. It features five-pinion gear sets, heat-treated stator shaft splines, induction hardened turbine shaft, an 8-friction-plate 3-4 clutch, and specially calibrated valve body. It also comes with a high-strength input housing, higher-capacity servo, and larger 2-4 band.

The 4L75 has undergone rigorous testing to ensure that it will hold up in even the harshest driving conditions. To validate that it would be robust enough for even the most insatiable speed junky, the tranmission was placed in a fourth-gen Camaro behind a LSX 454 making 627 horsepower. Two transmission were built for the car and sent along to the track in the off chance that the first prototype didn’t make it through the entire process.

“We went through nine sets of tires and two complete sets of brakes while validating this transmission,” Sampsel said. “We did over 2,000 cycles over six months at Milford consisting of accelerating from a dead stop with out spinning and running it all the way up until it shifted into fourth, then get on the brakes and slow it down to where you could go wide open and get it to make a fourth to second down shift then wind it back out through third, let it shift into fourth and then manually down shift it all the way down through first to bring it to a stop.”

The next step in the process was to run the car down a quarter mile more than 200 times over the course of two days—in other words, they put the transmission through hell, again. In order to complete the necessary amount of requisite passes, the team had to complete a run once every three minutes; basically hot lapping the car for two days straight.

In order to collect the necessary data, the car couldn’t be allowed to spin the tires to ensure that each pass was repeatable and put the exact same strain on the tranmission during each outing. The rear of the F-body was packed with about 500 pounds of ballast bringing the car’s total weight to around 4,200 pounds.

Even with the extra weight the car pull consistent 10.XXs and the prototype lasted through not only the 2,000 passes at Milford, but the 200 passes at the track without so much as a fluid change. The second tranmission they built ended up going into one of Chevrolet Performance’s SEMA cars that we will have a story on soon. Needless to say, the new transmission proved itself in real world testing and then some. If you’re looking for a stout tranmission, but don’t want to modify your floorpan, Chevrolet Performance has your answer.

Stay tuned to LSXmag.com for more SEMA updates!