It was finally time for an initial test drive where we tuned the carburetor on a chassis dyno. We learned several things after warming up the car and running it on the rollers. We found the used rear differential to be worn out and the gears and housing were rusty. The posi unit chattered like crazy and the clutches were gone, so we installed a new set of gears and a Detroit True Track differential to remedy that problem.
Changing the rear gear also required the installation of a new Speedometer drive gear.
The dyno showed us some lean areas in the fuel curve, so we tuned the 750 carb but were not happy with the result, so we switched the carburetor for a Holley Street Avenger 870 CFM unit to better supply the thirsty 454. This tuneup process was verified on the chassis dyno with a wideband oxygen sensor installed in the exhaust for optimum air fuel ratio.
We didn't do full power pulls on the dyno yet, as the car is super-fresh and is still not broken in. After a 4-500 miles we'll change the fluids again and see what it does. We'll be running Royal Purple synthetics to reduce friction as well as keep the moisture at bay.
We put some miles on the car and are quite happy with the result. The car is stunning in any light, turn heads everywhere does, and the performance is excellent. It feels new and tight, the steering is crisp, and that 454 makes tons of tire frying torque!