An easy way to make any vehicle a whole lot of fun to drive, is to stick a manual transmission in it. Unfortunately, manual transmission options have been slowly phased out of the OEM market, but that doesn’t mean you can’t have a man pedal in your ride. In this article, we’re going to look at what goes into a six-speed transmission swap.
Our 1994 Volvo Project Swedish Meatball didn’t come with a manual transmission from the factory. After some research, we found that people have six-speed swapped these cars with an LS engine combo like we’re putting in the Meatball. We wanted to make this process as painless as possible, so we reached out to Silver Sport Transmissions to get everything we needed for a six-speed swap.
Silver Sport Transmissions made this swap much easier. Their staff helped us pick out the right parts and sent everything we needed on one pallet.
Planning Is Everything
Since you’re likely going to be putting a six-speed in something that never had one, you better have a plan. Jumping into a project like this without thinking it through is going to put you at risk for experiencing some serious problems. Even with a plan in place, you’ll need to be ready to make changes to said plan along the way because you are guaranteed to run into issues you didn’t think of.
The first step in the planning process should include taking plenty of measurements of the space the transmission and bellhousing are about to occupy. This may seem like common sense, however, just doing the old eyeball measurement isn’t going to be good enough.
The transmission tunnel needed to be convinced a TREMEC Magnum F would fit….
You need to really crawl around the car to measure what space is available, and think about the other parts that need to be accounted for during the swap. A few basic things you need to consider include will you have enough space for the bellhousing, where the shifter will land inside the vehicle, the transmission mount, and how you will mount the clutch pedal.
Now that you have an idea of how much real estate is available, you can think about how the transmission will fit in the car. There can actually be an “easy-button” for this part of the process —someone might actually have already designed a kit for your application. If there isn’t a kit available, you’ll have to rely on your fabrication skills to get the transmission to fit in the car.
There are plenty of mistakes you can make when trying to plan for a six-speed transmission swap. Jeff Kauffman from Silver Sport Transmissions reveals a big mistake people make when tackling this project.
“We see a lot of people who just don’t do enough research, or listen to the wrong people. Message boards and social media is full of misinformation. There are also plenty of mechanics out there who aren’t doing this every day and can lead you astray. Your best bet is to talk to the experts, like Silver Sport Transmissions, or have your mechanic call us to make sure they’ve considered every potential issue and the possible solutions. We have people tell us every day and say, ‘I wish I had called you guys before I cut the car, bought the wrong part’ and so on.”
Planning and research goes a long way when you're tackling a six-speed swap.
Another mistake people make when planning a six-speed swap is future-proofing the build. Unless you’ve got a nitro-burning engine under the hood of your project vehicle, there’s always the opportunity to add more horsepower. You need to keep the possibility of future engine upgrades in mind when you’re planning the swap and looking for parts. It will save you time and money buying stronger parts the first time.
Selecting The Right Parts
After you’ve got a plan in place, it’s time to start picking out some parts for your six-speed swap. Besides the obvious things like the transmission, clutch, shifter, and flywheel, there’s plenty of other parts you’ll need. The right pilot bearing, slip yoke, wiring and sensors for various vehicle functions like reverse lockout, clutch linkage, and the correct hardware are just a few of the items you’ll need.
You can see how easy it would be to forget something on a project like this. That’s why we decided to work with a company like Silver Sport Transmissions.
“We see people trying to reinvent the wheel when it comes to taking on a six-speed swap all the time. We have mechanical engineers on staff who design our kits. Even if we don’t have a kit for your vehicle, we might have some advice or parts that will work. For items you can purchase off the shelf, we have years of experience in knowing which parts work together well, and which ones cause fitment issues,” Kauffman says.
The TREMEC Magnum F is a fantastic transmission. It is strong enough to work in just about any street car application, and it has great packaging characteristics.
The star of our six-speed swap is a TREMEC Magnum F transmission. When we started doing our research, it turns out the fourth-gen F-body six-speed transmission configuration works the best in a Volvo 940. With that in mind, and knowing how much horsepower we were shooting for, the Magnum F made the most sense.
TREMEC used the TR-6060/Magnum architecture to create the Magnum F. This transmission uses 4616 chromoly gears that have an increased face-width, triple cone synchronizers, and a stronger case. The transmission comes with a close-ratio gearset, featuring a 2.66:1 first gear,1.78:1 second gear, 1.30:1 third gear, 1:1 fourth gear, 0.80:1 fifth gear and .63 sixth gear . These transmissions are stout and can handle up to 700 pound-feet. of torque and 1,000 horsepower. So, the Magnum F shouldn’t have any problem handling the horsepower we’re going to throw at it.
We needed a clutch and flywheel to link our Magnum F and LS engine together. The team at Silver Sport Transmissions asked us a few questions about the vehicle, our engine, the horsepower goals, and how we planned on using the car. They decided a McLeod Racing RTX Street Twin clutch kit would work the best with our application.
We needed a clutch that could hold upwards of 800 horsepower, but didn't want something that would wear us out driving around town. The McLeod RXT Street twin clutch that was recommended by Silver Sport Transmissions is the perfect balance between the two requirements we had.
The McLeod RXT Street Twin clutch is going to provide a light pedal feel with smooth engagement and great release qualities. This is exactly what we wanted, a clutch that could hold upwards of 800 horsepower, but not kill our leg when we’re driving the car in traffic. McLeod achieved this balance by using discs that use ceramic facings. The other part of this kit that makes it street friendly, yet strong is the billet-steel flywheel it comes with. This flywheel allows for plenty of acceleration at stop lights, but it won’t have any problems launching the Volvo at the track.
One of the best things about using a six-speed swap kit from Silver Sport Transmissions is how complete it is. Everything you need to complete the swap can be shipped to your door. We were able to get our shifter, all the sensors and wiring, the correct pilot bearing, the hydraulic slave cylinder kit, and even the bellhousing all at the same time. It’s nice to have that piece of mind that all of the parts you need are coming and you don’t have to hunt around online to collect everything.
The Mangum F looks right at home under the Volvo.
Our Six-Speed Swap
For most popular vehicles there’s a good chance that a six-speed swap kit exists that includes all the mounts and hardware you’ll need. You might even get lucky and not even have to really beat on your vehicle’s floorboards or firewall to get the six-speed to fit. If you’re really lucky, the pedal box has provisions for a clutch pedal so you don’t have to become an engineer to make something fit. Well, for the Volvo 940 platform, these luxuries aren’t an option, so the team at Big 3 Racing had to do some work.
The first problem that needed to be addressed was creating some space for the bellhousing and transmission. Things were just tight enough the McLeod bellhousing wouldn’t fit behind the engine. To remedy this issue, the firewall and floorboards got a nice massage from the four-pound sledgehammer. With the bellhousing in place, it was time to bolt up the transmission, and some more clearance issues were discovered. Once again, the sledgehammer was called upon to make things fit.
Big 3 Racing did an awesome job creating the perfect transmission crossmember.
Remember how we said nobody made a six-speed swap kit for the Volvo 940? Well, that meant there is no direct-fit transmission crossmember available for this application. The team at Big 3 Racing looked at where the transmission landed after it was bolted to the engine and determined the OEM transmission mounting points would work. A custom crossmember was created out of some round tube to connect the transmission and the chassis. The final product is a one-off part that fits perfectly, and looks like it belongs on a full-blown race car.
After the brake pedal is shaved down, it will look like our Volvo came with a manual transmission from the factory.
The Volvo 940 wasn’t available in the United States with a manual transmission option. That meant finding a pedal box with the provisions for a clutch pedal was going to be nearly impossible. To overcome this issue, Big 3 Racing decided using a Wilwood reverse swing-style clutch pedal assembly with a remote reservoir would be ideal. The reverse swing pedal allows the clutch master cylinder to be mounted inside the car, therefore, there’s nothing mounted on the firewall in the engine bay. This required the custom fabrication of a mount for the pedal assembly under the dash of the car. The plan worked perfectly, and the pedal assembly looks like it came on the car from the factory.
Adding a six-speed transmission to a vehicle that never had one can be done, you just need to do your research and come up with a plan. Thankfully, companies like Silver Sport Transmissions and McLeod Racing can supply you with all the parts required to complete the swap. You can follow Project Swedish Meatball right here to see how well the swap works out in our Volvo.
