C3 Transmission Swap - Grabbin' New Gears, Part 2
As Promised, We Take Keisler Engineering's New T45-RS For A Test Drive
From the December, 2009 issue of Corvette Fever
By Alan L. Colvin
Photography by Alan L. Colvin, Keisler Engineering
Keisler Engineering, located...
Keisler Engineering, located outside of Knoxville, Tennessee, is the manufacturer of the T45-RS and was the location of the Corvette Fever test drive.
Last month I spoke about Keisler Engineering's new 5-speed transmission that had just been released for the C3 Corvette, the T45-RS, which is based on the Borg-Warner T-45 that was used from 1996-2001 in high performance passenger cars including the Cobra and 4.6L Mustangs. Keisler provides the new T45-RS in kit form and their proprietary and patent-pending designs for this tranny include a crossmember mount bracket, rubber transmission isolator, back-up wiring harness, forged quick release slip yoke, driveshaft, 5-speed shift pattern plate, template and tunnel cover, installation hardware kit, and an installation manual.
While I was on the 2-lane roads, I kept the car in 3rd and 4th gear most of the time and the car responded instantaneously to every shift with ease. There was absolutely no shifter vibration inside the car and I attribute that to the workmanship of the transmission, the newly designed shifter and the high quality of the rest of the assembly including the Keisler-built driveshaft. The transmission is a Double Cone transmission, with all forward gears and reverse fully synchronized, and it shifted up and down flawlessly. Even under very hard acceleration, the T45-RS easily found the next gear with absolutely no gear grinding or missed shifts.
In case you missed the last issue, Keisler buys the T-45 from reliable used transmission sources and then remanufactures each transmission in-house with a number of upgrades and custom features that greatly improves the reliability of the gearbox. The T45-RS rebuild includes new upgraded carbon fiber synchronizers, bearings, seals and gears (as required), a new high strength alloy front casting that allows the T45-RS to bolt up to the standard GM bellhousing bolt pattern, and a new super duty input shaft. As we mentioned last month, the transmission comes in two builds, 350HP and 425HP. The primary difference between the two is that the 425HP version uses the larger 26-spline input shaft while the 350HP version uses the 10-spline input. The same gear ratio is used for both versions and is as follows: 3.37 1st, 1.99 2nd, 1.33 3rd, 1.00 4th, .67 5th; 3.22 Reverse which equates to a 33% drop in engine RPM in 5th gear. Keisler also offers a choice of electronic or mechanical speedometer output for the T45-RS and uses a high strength 31-spline output shaft.
Keisler maintains around 100...
Keisler maintains around 100 cores that are carefully inspected prior and during teardown.
The T45-RS also uses a custom billet aluminum short throw shifter that has been custom designed to work in all 1968-82 Corvettes, and an optional C3 replica shift handle is also available that not only gives you an original look but also places the shifter at the correct height. On a final note, each T45-RS is 100% spin tested and leak checked prior to shipment and comes with a 6-month warranty (extended warranty available at extra cost).
As I said last month, Shafi Keisler invited me to fly up to the Keisler plant for the T45-RS install and to test drive the new transmission for myself. Our test drive consisted of some 2-lane back roads through the hills around Knoxville as well as some high speed expressway driving. When you are testing a transmission, you need to drive the car in a multitude of driving conditions to really get a feel for the car and how that particular transmission is performing in that car. Over the years, I have driven thousands of miles in Muncie 4-speed equipped cars but I had no idea what to expect since I had driven very few Mustang 5-speeds except for an '84 SVO Mustang I had bought new.
As we got out on the road, the first thing I noticed about the T45-RS was how similar the shift gate was to the original Muncie in contrast to the Tremec TKO. The T45-RS shares many internal components with the famous T-56 6-speed and because of that fact, I assumed that the gate would feel the same or similar to the TKO. But I was wrong. A TKO typically feels very "notchy" when you shift from one gear to the next where the T45-RS feels very much like a new Muncie transmission felt back when they were brand new. The T45-RS shifts very easily and can actually be shifted with one finger, even with the optional C3 replica shift handle that we used on this install. The original Muncie transmissions obviously had a much narrower (1-2) gear drop since it was a 4-speed so the gear ratio gap with the T45-RS 5-speed with the 350/350HP smallblock in this car seemed almost the perfect match.
Keisler stocks several thousand...
Keisler stocks several thousand individual components to build manual and automatic overdrive transmission systems for the aftermarket. Everything is barcoded and a wireless scanning system updates the server as to shipping and sales needs.
Out on the expressway, the T45-RS performed very well with no complaints. Whether at low or high speeds, I could hear absolutely no gear whine whatsoever. In fact, this transmission is one of the quietest transmissions I have driven in any vehicle...ever. Even at high speed at 75-80 MPH, there still was no indication of any vibration through the shifter and that fact truly surprised me. Most cars have some drivetrain vibration at some point in their power curve (especially manually-equipped cars) but I never found it with the T45-RS and I was truly amazed by that fact. I drove the car for about an hour and I enjoyed every minute of it. In fact, I may just use this transmission for one of our new project cars this coming year.
At the end of the day the bottom line was clear; If you are looking for a manual overdrive transmission that shifts great, can handle adequate power without breaking, is dependable, durable, has all the latest upgrades and features expected in today's transmissions, has a warranty and costs about $1000 less than a TKO package, then the new Keisler T45-RS should be a serious consideration for your next C3 Corvette project. One last thing: We videotaped the test drive and we now have the drive on corvettefever.com as well as the keislertv.com website. You can also see the two Keisler versions of the drive on youtube.com so check it out.
Special fixtures are used...
Special fixtures are used to disassemble and assemble the T45-RS. The mainshaft is built up, and then assembled to the transmission along with the shifter rail, forks and shims.
At the rebuild stations, assembly...
At the rebuild stations, assembly parts are set to the rebuild area by job. Each unit's information is barcoded and stored on the server, including builder, day, quality check associate, and sales order.
One of Keisler's key ingredients...
One of Keisler's key ingredients to their transmission kits is their driveshaft program. Keisler builds all their driveshafts in-house on their Hines driveshaft cell from lightweight, high strength steel that is automatically welded and computer balanced with premium solid sealed U-joints. Here Shafi explains the first step of their in-house Hines driveshaft manufacturing cell. At this process a specially prepared lathe cuts the driveshaft tubing, chamfers it both inner and outer for a deep penetration weld.
Next, these precision yoke...
Next, these precision yoke chucks hold the parts so they don't galled up or bind during the pressing stage. Keisler invested more than $150,000 in this Hines Driveshaft manufacturing cell. The cell builds OEM grade driveshafts for the highway, which is a requirement for many road going commercial vehicles.
C3 Corvette components shown,...
C3 Corvette components shown, in preassembled form. L-R: Keisler's forged slip yoke with 4140 billet caps; Neapco HD sealed permanently lubed high performance u-joints assembled to Spicer weld flanges.
Michael is doing the first...
Michael is doing the first stage of assembling the driveshaft. Here the individual components are set to the Hines driveshaft press. A hydraulic ram presses all of the components together with precision alignment.
Here Michael is building a...
Here Michael is building a Corvette driveshaft on a Hines Spicer driveshaft machine. Runout is measured at each end of the shaft and the middle-3 places in total. Runout in the middle is corrected by the hydraulic ram with linear scale (lifted up). Next, the driveshaft is automatically welded. Next, the dynamic balance is checked, and balance weights are welded at the correct rotation angle, as needed. The d/s then goes on to masking, paint, then serialized with a sticker of certification.
In the fabrication and welding...
In the fabrication and welding shop, we can see Keisler's C2-C3 Corvette replacement crossmember and frame brackets. The crossmembers are box construction to minimize driveline flex, mig or tig welded, then powder coated. In the background are A-41 automatic transmission extension housings and Camaro crossmembers.
Kit components including clutches,...
Kit components including clutches, bellhousings, speedo-cables, shifters and numerous other parts are picked and scanned at the pack-out lines, where they are married up with the boxed transmission from the assembly lines. In 2006, Keisler went to a Lean Production System, with the help of the University of Tennessee's Industrial Engineering department. This dramatically reduced inventory and lead time, customer satisfaction went up and less floor space was used to get the job done.
Dick McCord, the principle...
Dick McCord, the principle design engineer of the Borg Warner T-56 and now Keisler's chief engineer, demonstrated shifting of the T45-RS on the Test Stand machine. The Test Stand is one of the original machines from Muncie Transmission plant used in the '90s. It has a large servo motor that runs the transmission as high as 6000 rpm. Notice the safety shield. The Test Stand also has a full computer control and data collection system, and the machine is designed to run 24/7 and record the shift quality and transmission performance.
T45-RS as it is packed up....
T45-RS as it is packed up. Special dunnage was developed to support the transmission. Each unit is painted either argent silver (GM) or electric blue (Ford shown), or left natural for the customer to paint or polish.
Now we were ready for the...
Now we were ready for the test drive in the C3.
When you are testing a transmission,...
When you are testing a transmission, you need to drive the car in a multitude of driving conditions to really get a feel for the car and how that transmission is performing.
As we got out on the road,...
As we got out on the road, the first thing I noticed about the T45-RS was how similar the shift gate feel was to the original Muncie in contrast to the Tremec TKO.
While I was on the 2-lane...
While I was on the 2-lane roads, I kept the car in 3rd and 4th gear most of the time and the car responded instantaneously to every shift with ease.
A TKO typically feels somwhat...
A TKO typically feels somwhat "notchy" when you shift from one gear to the next where the T45-RS feels very much like a new Muncie transmission felt back when they were brand new.
Out on the expressway, the...
Out on the expressway, the T45-RS performed very well with no complaints. Whether at low or high speeds, I could hear absolutely no gear whine whatsoever.
The T45-RS shifts very easily...
The T45-RS shifts very easily and can actually be shifted with one finger if you like, even with the optional C3 replica shift handle that we used on this install.
Even at high speed at 75-80...
Even at high speed at 75-80 MPH, there still was no indication of any vibration through the shifter. Most cars have some drivetrain vibration at some point in their power curve (especially manually-equipped cars) but I never found it with the T45-RS.
This transmission is one of...
This transmission is one of the quietest transmissions I have ever driven in any vehicle...ever. I drove the car for about an hour and I enjoyed every minute of it.
|Various T45-RS Videos
|Test Drive Short Version
|Test Drive Long Version
|T45-RS Install Part 1
|T45-RS Install Part 2
|T45-RS Install Part 3
|T45-RS Install Part 4
|Rebuild And Testing Video
|Compare Video Of T45-RS And Muncie, Includes TKO PF
|Dick McCord On T45-RS Design Process
|Wes Morgan Driving