65-66 Mustang 5 & 6-Speed Conversions from Modern DriveLine
We offer the most complete line of five and six speed conversions for Mustangs.
Our line of products offer simple ways to upgrade your 3 or 4 speed to a Tremec five speed or a complete automatic to five or six speed overdrive, we have you covered.
Experience the MDL difference
- We extend the manufacturer’s warranty by an extra year… and that’s from date of install.
- We offer best in-the industry customer service.
- When you purchase a complete MDL Conversion Package you get, life-time technical support.
T-5 Five Speed Single Overdrive Conversion up to 450hp
Inline Six cylinder conversions
Starting in 1965, Ford built many of these pony cars with 170/200 inline six cylinders engines with manual shift three speed transmissions. The three speed transmission was budget minded and were OK in their day, Fast forward to today, these same transmissions are worn out are in the need of replacement. The answer is a Tremec T-5 five speed with an overdrive. This allows the Mustang to travel comfortably at highway speed at mid 2,000 rpm range. Installing a T-5 into a classic Mustang is easy. Using most of the three speed parts, like the bell-housing, flywheel and clutch linkage, all that is needed is a new conversion clutch, adapter plate, T-5, crossmember and a few other supporting parts. No tunnel modifications are needed and the shifter location is retained.
1965 to 66 Mustang used a 2.77 3 speed with a 8.5″ clutch set. These are easily identified by looking for three starter bolts. If there are 2 starter bolts this means the flywheel is a 136 tooth with a 9″ clutch. Which was not stock, and means that someone has transplanted a later driveline into the car. Regardless if which bellhousing you have, MDL offers several T-5 adapter plates to to make this conversion easy.
OK, your classic Mustang is equipped with an automatic. MDL has a compete conversion package to make this conversion easy. Our T-5 conversion kit includes hard to find items like new inline six cylinder flywheel, conversion clutch, we also offer a reproduction ‘easy to install’ clutch pedal and slip yoke or custom made driveshaft and everything in between.
Manual to Five Speed
Five Bolt Block 260/289
65 Mustangs were equipped with five-bolt 260 and 289ci blocks. If you are unsure if your block is a 5 bolt, look at the starter. On the bellhousing to engine flange, there is a bell locating dowel pin. Above the dowel, there should be no bolt indicating a 5 bolt block and bell. If there is a bolt above the dowel this is a 6 bolt block and bell. If you have a 6 bolt block, skip to the next section” Six Bolt Block”.
If your Mustang is a manual shift, this conversion will cost less than the automatic conversion. Using many of the OEM parts, like the bell housing with an adapter, the flywheel, clutch and mechanical clutch linkage. The U.S.A. made MDL narrow pattern adapter, MD-401-2101, locates the transmission into the correct position, and fits the tunnel without cutting the floor. Since the T-5 has the same input shaft spline and pilot tip, it will slip into place. MDL has a complete line of in-house handmade clutches, with the choice of Cast or Light Billet flywheels, should you need a replacement or plan to increase your HP the LBS may be a good choice.. For those who want an effortless pedal feel or are challenged by a heavy pedal, MDL offers you an internal hydraulic upgrade. If you are running a fair amount of power or run your Mustang in motor sporting events, the ‘QuickTime’ scatter shield is available and allows the T-5 or TKO to be installed without an adapter plate. The QuickTime bellhousing is built to use either the stock clutch linkage. clutch cable, internal T/O or external hydraulic release to provide the smoothest pedal feel and give you the most header clearance.
Six Bolt Block 289/302/5.0L
The mid-year 1966 Mustang was equipped with six-bolt blocks that carried through 302 and 5.0L HO of the ’90s. With this change comes the wide pattern “Top Loader” four-speed.
If your Mustang is a manual shift, this conversion will cost less than the automatic conversion. Using many of the OEM parts, like the bellhousing with an adapter, flywheel, clutch, and mechanical clutch linkage. The U.S.A. made MDL wide pattern adapter, MD-401-2102 for a T5z or the MD-401-2108 for the TKO “Low Profile” transmission, locates the transmission into the correct position, and fits the tunnel without cutting the floor. MDL has a complete line of in-house hand-assembled clutches for various HP ratings, cast, and Light Billet Steel flywheels should you need a replacement or plan to increase your HP. For those who want an effortless pedal feel or are challenged by a heavy pedal, MDL offers you an internal hydraulic upgrade for use with the top loader bell. If you are running a fair amount of power or run your Mustang in motor sporting events, the QuickTime scatter-shield is available that will allow the T-5 or TKO to be installed without an adapter plate. The Quick Time bell-housing is built to use either the stock clutch linkage, clutch cable, internal T/O or external hydraulic release to provide the smoothest pedal feel and give you the most header clearance.
TKO Five Speed Single Overdrive Conversion up to 750hp
If you are making big power or just drive your Mustang really hard, the TKO series five-speed is a great choice. Our low profile top covers allow for the TKO to be bolted in without enlarging the tunnel. In order to install the TKO five-speed at the correct drive angle, the floor support has to be moved back over the narrow section tail shaft housing to retain the stock drive angle. This can be done by removing the factory spot welds and relocate the support back and welding in back stronger then it was. With the floor support relocated, the stock 65-66 crossmember is reused. We are asked all the time why we don’t sell a 65-66 Mustang TKO crossmember? The reason is we would have to lower the tail shaft housing so much that the drive angle would be all wrong. When you are making big power, you don’t want that.
T-56/Magnum Double overdrive Six Speed Conversion
Are you considering a six-speed in your classic Mustang?
Are you willing to enlarge the transmission tunnel? If so, we can help you with a very complete six-speed Magnum package and advice to make it happen.
Our Magnum six-speed package comes with a new tunnel extension and crossmember that connects to the subframe. This cross member is important because the floor support is no longer used to hang the Magnum from.
The Magnum is a perfect choice when only the best will do. From daily commuting to pro-touring, the Magnum has the right gear ratio and strength to handle up to 1,000hp.
Give us a call, we will be glad to discuss the detail of the project and make a suggestion on which gear ratio is best the motor type that is being installed.
Automatic or full conversion packages
Modern Driveline has perfected the auto to five-speed conversion. When you contact us we will ask you a shortlist of questions to better understand your needs and wants. Using our complete line of products, we can offer you everything you need to remove an automatic and completely replace the stock 3 or 4-speed gearbox. If you project demands everything from scratch, MDL has you covered.
When removing an automatic, nothing remains. Our automatic kit provides everything from the block to the second u-joint. It is important to know which balance crank is installed in your motor. 289/302 up to 1980 from the factory were 28 oz imbalanced. All 5.0L from 81-95 are 50 oz imbalanced unless the crank as been changed. Today there are many that are building zero balanced SBF like Ford Racing. Let us know what you are you planning to run. We will suggest the right clutch to run based on your horsepower and driving style. In most cases, we can have a detailed quote prepared for you in under 15-20 minutes.
All Conversions have clutch release options and are as follows;
Mechanical linkage – Mechanical linkage may be retained if your car is a manual now. The MDL Muscle Z-bar kit can be used as an upgrade and requires the use of the OEM springs. If a 1979-1993 T-5 or TKO aluminum bell-housing (all designed for cable release) is used in a vehicle that is equipped with mechanical Z-bar, These bells require a conversion fulcrum adapter kit for use with a mechanical fork. The fulcrum adapter kit has a spacer/pivot block and places the fork in the correct location. MDL can pre-drill the mounting holes for you with our fixture to ensure mounting hole location is correct. Quick Time bell-housings are equipped for use with either cable or mechanical clutch release.
Cable clutch release – Since T-5, TKO, and Quick Time bell-housings are designed for a cable release, a matching fork is required. It is important to know the 3 or 4-speed mechanical release “clutch” can no longer be used as it will be too tall.
MDL offers a cable release clutches for 10″ long pattern as well as the 10.4″ Metric bolt patterns. The pressure plate lever height is lower and the release is faster.
To use the stock clutch pedal, MDL has engineered a cable kit that mates with the stock 65-66 Mustang pedal and come complete with a firewall plate, custom double adjustable cable the is routed round exhaust system.
Hydraulic release – MDL developed a complete line of hydraulic clutch release systems we call our LF (Light Foot) Series.
The master cylinder mounts on the firewall using our mechanical linkage that connects to the stock clutch pedal. The linkage provide proper leverage and control while providing design flexibility. Using the T-5 and cable fork, our external slave cylinder mounts to the back of the bell-housing fork opening, pushing the fork forward. Our hydraulic system gives you the most exhaust clearance while provide the softest pedal effort.
If you are undecided as to which clutch release system is right for you, we can help you through the process of what right for you.
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