Mustang Restomod Guide: Drivetrain
Modernize Your Drivetrain With Crate Engines, Strokers, And Overdrive Transmissions
For the past 10 years or so, the PerTronix Ignitor and Ignitor II electronic ignition modules have been a popular replacement for the archaic points and condenser in vintage distributors. Now PerTronix offers the electronic upgrade in a new billet distributor.
The complete, ready-to-drop-in distributor is loaded with features, including the Ignitor II module already installed in the CNC-machined aluminum housing. The bottom half contains a self-lubricating, oil-impregnated, copper-powder bushing to reduce friction and high-rpm vibration. Available from Mustangs Plus, the PerTronix billet distributor fits 221, 260, 289, and 302 small-blocks. Cleveland and FE versions are expected in the near future.
We Be Stroking
Replacing a 289 or 302 with a stroker small-block is an outstanding way to gain performance in an early Mustang without detracting from its vintage appearance. With a 347 version of the late-model 5.0L, you get 58 more cubic inches thanks to a 0.040-inch overbore and longer stroke crankshaft. The external dimensions are the same as a 289 or 302. Other displacements are available, and most come with the newer-style roller camshafts. The newer block bolts right up to bellhousings for either a late-model AOD or five-speed, or a vintage C4 automatic or four-speed. You'll have to locate an adaptor for a vintage-style clutch linkage because late-model blocks don't have the threaded boss for the linkage stud.
The 5.0L is based on the same engine family as vintage 289s and 302s, so valve covers, intake manifolds, and accessories are typically easy bolt-ons.
Small-block Ford stroker engines are available, either as short-block or long-block crate engines, from a number of sources, including Ford Racing, Smeding Performance, Coast High Performance, and Roush Performance.
Stainless Works has introduced a larger version of the popular Try-Y headers for small-block Ford engines in '65-'73 Mustangs. Featuring 151/48-inch primary tubes for improved flow, the headers are manufactured from 304 stainless with 11/44-inch thick, CNC laser-cut flanges. The tubes transition into 2-inch intermediate tubes before dumping into 3-inch collectors with either a three-bolt flange or a patent-pending slip-fit design, allowing the exhaust system to slip over the collector for securing with a T-bolt clamp. Dyno tested, the Stainless Works 151/48-inch Tri-Ys made 36 more horsepower at the rear wheels compared to traditional 111/42-inch Try-Y headers.
It's the big daddy of Mustang bolt-ons. Originally a rare option for '66-'67 Shelby GT350s, the Paxton supercharger is back for carbureted, vintage Mustangs with a modern Paxton Novi 1200 supercharger. Designed to fit '65-'66 Mustangs, the Novi blower generates 6 to 7 pounds of boost and works with stock four-barrel engines or--better yet--modified engines. With the carburetor housing, brackets, and all other components needed to install the system, it's fairly complicated for a bolt-on. And it's not cheap. But once you feel the boost, it's worth it.
For more than a decade, installing an AOD transmission into a vintage Mustang has been a popular upgrade compared to original C4, C6, and FMX three-speeds. With a modern AOD, you get reduced engine rpms at highway speeds, better fuel mileage, less engine wear, quieter cruising, and improved off-the-line acceleration when used with lower (numerically higher) rearend gears. These days, it's practically a bolt-in swap because much of the research has been done.
Used AODs are available from many sources, but if you're going through the trouble of making the swap, it's best to choose one that has been rebuilt to performance specifications by companies such as Performance Automatic, Lentech Automatic, and B&M Automotive.
In addition to the actual transmission, you'll also need an aftermarket crossmember, a flexplate, a shift linkage to connect the AOD to your vintage-style shifter, a kick-down linkage, and a throttle-valve cable to adapt to the carburetor. The cable acts as the equivalent of the older vacuum modulator. In most cases, the driveshaft will need to be shortened by about 1 inch.
Several companies, including Performance Automatic and Ron Morris Performance, offer adaptor kits for installing an AOD in early Mustangs.