Photo courtesy: Evan Azzo Photography

Just like an ice cold beer on a hot summer night, there are certain things in life that go together perfectly when paired. Take for example, Robert Karagovski and his ROUSH Performance supercharged 2015 Mustang GT. Boasting nearly 700 horsepower at the rear feet, Robert knew his factory clutch assembly and 6-speed manual transmission were not long for this world at that level of power.

Sure, the instant torque of the ROUSH 2.3-liter TVS roots style supercharger wasn’t going to grenade his drivetrain with a flick of the throttle, or the occasional wide-open pull. But like many Mustang enthusiasts, Robert knew it was time to upgrade to a stronger, more robust drivetrain setup if he ever wanted to race the car properly.

When it comes to manual transmission solutions for the Mustang community, two of the industry leading suppliers Tremec Transmission and McLeod Racing, have quickly become some of the most well-regarded drivetrain syndicates in the biz. Robert tells us in his own words why swapping to a Tremec Magnum XL 6-speed manual transmission and a McLeod Racing RXT twin disc clutch (paired with its lightweight flywheel) was the biggest step he could have taken towards a reliable drivetrain setup.

The new Tremec Magnum XL 6-speed manual transmission, supplied from Neighborhood Auto & Performance.

“My buddy Ken Fournier at Neighbourhood Auto & Performance really helped me out here,” Robert told us, when we asked him how difficult the swap from the Getrag MT-82 to the Tremec Magnum XL was.

“He was the one that did all of the modifications to make it work properly, and came up with some neat ways on how to do it. There were some issues initially with clearance in the tunnel for the reverse lockout, so he decided to cut some of the firewall away and modify the tunnel slightly to give it some room.

Ken decided to reconnect my reverse lockout in a permanent fashion, so that I wouldn’t have to use any springs or a button to make it go in reverse.”

“It goes in with no effort at all,” Robert continued. “Ken ended up dry-fitting the the transmission and doing all the measurements needed to allow another company, Precision Shaft Technologies, to make us a custom aluminum driveshaft.”

What Robert ended up with was a one-piece aluminum driveshaft which was outfitted with a billet yoke, and utilized 1350-grade joints.

“They made a custom piece to fit on the super 8.8-inch rear end. We ended up using the Tremec shifter, but used a dust boot from a ’11-’14 Mustang to close up the hole, and keep the heat from the exhaust and the drivetrain away from entering the cabin. This is a must if you plan on driving it around town, and not only on the track,” Robert said.

The re-splined McLeod clutch assembly, ready for action.

At nearly 700 rear-wheel horsepower, it’s easy to see why Robert was sweatin’ the reliability of the factory drivetrain assembly. “I wasn’t happy at all with the MT-82 transmission,” Robert said in regards to shifting the stock transmission with all of the newfound power.

Robert boasts nearly the entire ROUSH Performance catalog available for the ’15+ Mustang on his car.

“There were always issues with power shifting into 3rd gear. Once you were in gear it was fine, but it just didn’t have that solid muscle car feel to it. It seemed to be fine with the stock engine’s power levels; but once some power was added, it just seemed to get worse.”

It’s understandable why the stock transmission would slowly begin to fade away at that power level, but the factory clutch assembly was in even worse shape.

“In my opinion, McLeod makes some of the best racing clutches out on the market,” Robert entailed. “The RXT is very grabby, and it just hooks like no other. The clutch feels like butter to be honest, and is probably the easiest on the leg. Between using the RXT and the supplied lightened flywheel, everything just feels right.”

He continued, “Great engagement with no slipping at all was something that was very important to me when deciding which clutch to go with. I originally used the RXT in conjunction with my factory MT-82 transmission first, but I was able to send my clutch discs back to McLeod to get the hub re-splined. This was seriously amazing, as I didn’t have to buy a new clutch! The high release point on the pedal with the RXT really makes shifting fast and easy when racing,”

“We all know that the MT82 isnt the strongest transmission to begin with. After modifying my Coyote powered Mustang, the factory transmission was not holding up so well. With my Roush 2.3-liter TVS supercharger paired with a 79mm pulley, and a custom tune by Chris Jones at Blow By-Racing, I’m making nearly 700 rear-wheel horsepower.

I am a huge ROUSH fan, so I decided to use as many of their parts as I could to create my own. As the power increased, the factory MT-82 kind of went kaboom. It seamed very sloppy to begin with, and the shifts were very long due to the remote style shifter. I ended up losing third and fourth gear while racing one day, if you can imagine that. I knew it would happen, but I was just waiting on it.

After doing some research, I decided to go with the Tremec Magnum XL because of the direct-shift 6-speed and getting away from the remote style shifter. What I like about this combination most, is that I can continue to use my McLeod Racing clutch assembly. I just felt that this was better for my application and would give me better shifts.”

We asked Robert what the biggest takeaway from his newfound setup was, and what enthusiasts can expect if they own a high horsepower Coyote powered Mustang.

“Tremec Transmission and McLeod Racing did an amazing job designing these two components, and I couldn’t be happier with their ability to handle my ROUSH Performance supercharged Mustang GT. I would highly recommend them both to anyone thinking of doing this swap. They will not be disappointed!”

We couldn’t have said it better ourselves, Robert.

Robert told us that shifting the whole shebang really doesn’t compare between the two setups, and that the Magnum XL is hands down better in all aspects.