Inside, a cop 125 mph speedo replaced the stock 85 mph piece. A police oil-pressure gauge
Rounding out the chassis, my original plan was to salvage a set of 15x7-inch ventilated steel police wheels. Luck seems to runs in threes-besides finding the Fifth and the fresh re-manned 360, the boneyard gods were kind and a gleaming set of 15x7-inch forged aluminum road wheels were dangling from the hubs of an early '80s Dodge Mirada. SCORE! The wheels came complete with chrome center caps and lug nuts, the perfect stylish mags for the Fifth, at the scrap-metal price of $16 each. To plant the Fifth to the pavement, a set of high-performance tires would be a key part of the formula. No junkyard shopping for the sticky meats, here a new set of 245R60-15 BFGoodrich T/A Radials were wrapped around the road wheels at all four corners; a lot of tire to be sure, but an easy fit in the M-Body's large wheel wells. Did the suspension and wide rubber make a difference? There's no gray area here, it was like night and day. The Fifth originally wallowed down the road like a sow in mud. With the good wide rubber, KYB shocks, and the full police suspension, it sticks.
The cop cars also came with 125 mph police speedos, while the speedometers in all of the civilian M-Bodies of the era had the pitiful 85 mph units. So I bagged the speedo as well as the high-quality electronic oil-pressure gauge and sender, another police-only item. Police cruisers were equipped with an extended oil fill pipe for the valve cover-snagged that too. Other cool police stuff included the police tranny, engine, and power steering coolers, electric fuel booster pump (late M-Bodies only), and 100 amp alternators to name a few. Nice pieces all, but for now those will have to wait for another day.
Building the Fifth turned out to be a cheap, quick, and satisfying project. Because all of the parts were bolt-ins and there was no resto detailing, the car came together remarkably quickly. The entire drivetrain swap was done in a weekend, and the car was on the road. The rear suspension was done in an afternoon; ditto the front. Since the body and interior were cherry, the focus became upgrading the wimpy stock mechanicals with H/D or high-performance components. The sweetest part was that practically everything was scammed from the wrecker's at rock bottom prices. The exhaust system and tires meant opening the wallet, but a lot of the parts such as the ignition, radiator, air cleaner, carb, etc. were cast-off or pack-ratted items already taking up space in the garage.
Is it done? These are heavy cars and ours could use more brake. The stock 11-inch front discs are the same size used in the police package M-cars, but a set of late B- or R-Body 12-inch discs can be swapped up front by changing the caliper bracket and adding the big rotors. Out back, the Fifth has 10-inch drum brakes, the same as used in the last few years of M-Body police production, though earlier M-Body police vehicles used 11-inch units. Big brakes all around will eventually be added.
Stock, the Fifth Avenue was luxurious, but woefully underpowered and unstable around corners or at speed. Nearly everything under the skin that makes the car go has been replaced, and the entire character of the car has changed. Though it looks like stock, it hauls, hooks, and handles better than it has any right to, and is downright fun to drive. The hardest part of the build had to be handing the keys over to my better half when it was done.