Will we soon need a commercial driver’s license to operate a Corvette? The seven-speed manual transmission in the ’14 C7 Corvette seems to beg the question. Are we shooting for a 13-speed manual transmission in supercars someday? Is a revival of the two-speed rear around the corner? A seven-speed transmission might make sense in certain industrial applications, but in the world of high-performance driving it smacks of one-upmanship to me.
Let’s go back to simpler times, the days of four-on-the-floor and steep gears. When some began to cry for better fuel economy, the five-speed was born. Back in the late ’60s, the hot setup for highway driving was a Hone Overdrive unit developed by Fred Hone. Today a similar solution is available with Gear Vendors’ durable overdrive units that enable the retention of most of the older four-speed transmissions. Cutting up tunnels to fit a huge aftermarket transmission is less appealing, as it loses a measure of the car’s authenticity.
GM began offering the BorgWarner T10 four-speed transmission in certain ’57 models. In the ’63 model year, GM introduced its new Muncie transmission, which was similar in design to the T10 but stronger. In muscle car land, three Muncie four-speeds are players: the M20 wide-ratio, the M21 close-ratio, and the M22 Rock Crusher close-ratio. The wide-ratio M20 is fitted with either a 2.52 or 2.56 First gear, while the close-ratio M21 and M22 come with a 2.20 First gear.
In comparison to the M21, the Rock Crusher M22 features stronger alloy gears that are straight cut for the least amount of end load. If you want to spend some time at the drag strip, the Rock Crusher is the transmission of choice. Though some might complain about the signature M22 gear whine, most consider that whine an announcement of a car that’s all business.
While plans for our MaliBeater ’67 Malibu project car include a number of drivetrain combinations, it was clear that the very first modification had to include an engine upgrade and the requisite conversion from a three-on-the-tree to a four-on-the-floor. MaliBeater’s owner, Brad Van Hemert, was in complete agreement and just happened to have a Muncie M22 sitting around. Parts were ordered from Summit Racing; Matt Renz at Midwest Muscle Cars in Lake Zurich, Illinois, was summoned; my car buddy Mark Webster received my urgent plea for help; and we got to work. The entire process turned into a great time getting the MaliBeater closer to ready for the Week on Woodward and the Dream Cruise on Woodward Avenue in August. If that M22 gear whine is loud enough, it might just make it to this year’s Street Machine Nationals when it returns to DuQuoin.
Bolting the mounting plate to the transmission is the first step in installing the Hurst Competition Plus shifter. Make it tight, but don’t go gorilla on it.
The shifter is bolted to the mounting plate. Do not remove the white plastic rod at the bottom of the shifter, as it retains neutral while rods are attached and adjusted for each gear.
The Hurst shifter arms are bolted to the transmission. The length of the linkage rod attachment points is adjusted and joined to the shifter via supplied clips.
Patience and precise adjustments for the linkage length will produce excellent shifter operation. If at all possible, do the shifter installation on your workbench, as it will make the job simpler and more exact. Once installed, the Hurst shifter felt solid and accurate.
The ’66 327/350 L79 motor that is going in the MaliBeater came stock with this 6-quart oil pan. Though the extra quart would have been a nice bit of engine insurance, it was too big for the Malibu chassis. The pan and stock oil pickup were removed, and all mating surfaces were scraped and cleaned.
With the pan off, my buddy, Chevy engine guru Mark Webster, noted that the pistons were GM PN 3866954. Webster was confident that these pistons were original and probably indicated that the engine had never received an overbore. Sure enough, a quick online search confirmed Webster’s hunch. Though this engine might have received new rings and bearings, it apparently has maintained its original 11:1 L79 pistons.
A new Melling oil pickup was pressed into the existing oil pump. Matt Renz then spotwelded the pickup to the pump. Welding the pickup tube to the pump is highly recommended. Though it might seem tight upon installation, the pickup can loosen up quickly when subjected to normal operating temperatures.
New Felpro oil pan gaskets were used for the oil pan installation, with gasket sealer applied liberally on the front and rear ends of the pan.
The flywheel should be resurfaced at the local machine shop. However, since the flywheel showed signs of a recent resurfacing, Webster decided that a DA with 40-grit paper would prepare the surface sufficiently.
Using a torque wrench, the flywheel is torqued to 60 lb-ft.
After the flywheel was properly torqued, a brake cleaner or similar product is applied to remove any grease and fingerprints left there from handling.
Hays Clutches offers high-quality 10½-inch Street Performance kits for a wide range of vehicles. They are made in the USA and were widely used back in muscle’s golden era. The supplied plastic pilot shaft installation tool enables correct placement of the clutch disc.
The Hays pressure plate is bolted to the flywheel with the fasteners provided in the kit. Note the plastic pilot shaft is still in place.
The Hays pressure plate is torqued to 35 lb-ft. The pilot shaft is then removed.
The stock bellhousing used on the 283 is perfectly fine for the 10½-inch clutch setup on the 327. Torque the bellhousing to 25 lb-ft.
Getting the transmission in place is a lot easier with an extra person to carefully work the trans input shaft into place. If the pilot shaft installation tool was used properly, the trans will line up perfectly.
Unbolt the Hurst shifter stick, leaving the shifter unit and linkage in place. Webster then lowered the engine, bellhousing, and transmission assembly into the engine compartment. I took pictures.
A floor jack was placed under the transmission to lift it up. Once the transmission was confirmed centered in the tunnel, the location of the shifter was marked on the tunnel. A big hammer and punch were used to create a guide hole. Renz first used a 2½-inch hole cutter to cut the tunnel, then opened up the hole using a pneumatic cutter and saw. Do a little at a time, checking how big the hole needs to be by lifting the transmission into place after each cut.
Renz did a great job opening up the hole without cutting away too much metal. The hole will be left open until the car is running. It will then be determined if more metal should be removed.
An Energy Suspension transmission mount is attached to the Muncie M22. The high-quality mount is especially helpful to absorb and manage high-rpm shifts.
The transmission crossmember is lined up with the mount and then bolted in place. There will be a time when this crossmember will be restored properly, but for now we are going for the as-found, muscle car beater look.
The Parts Place makes this excellent bench seat shifter hump for $109, well worth the expense. The hump will not be installed until we are completely happy with the clearance at the trans tunnel opening.
MaliBeater has not been on the ground for a few months. Those 15-inch Coker/Firestone tires look great. Present owner Brad Van Hemert said that the car is sporting big-block front springs installed by the previous owner, Allan Scafer. That nose-up look might work for the final stance, but some ride height tweaking could be employed as well. Next up for the MaliBeater: brakes and suspension.
