C3 Big-Block Engine Swap - Big-Block Party

Part 3: Prepping our '69 for the installation of a modern, EFI big-block

Paul Sisia Aug 21, 2011 0 Comment(s)
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It didn't make sense to reinstall old brake pads or shock absorbers, either. We chose to upgrade both the pads and rotors with new units from EBC Brakes. They're specifically designed to work with stock Corvette calipers, and their rotors are slotted and partially drilled to avoid cracking. We painted the calipers with caliper paint to complete the look.

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For shock absorbers we were back on the phone with Summit Racing, whose techs recommended QA1 adjustable gas units. We also replaced the stock rear multi-spring setup with a single composite spring from Volunteer Vette. It'll deliver better ride quality and reduce a fair amount of weight as well. (Volunteer provided our front big-block springs, too.)

One of the biggest and most noticeable upgrades we made was to eliminate all the stock pulleys and belts and install a Vintage Air Front Runner serpentine belt system, which came complete with a new and more efficient A/C compressor, power-steering pump, and 140-amp alternator.

The Front Runner system is truly a sight to behold. Everything is polished or chromed, the mounts are all one-piece 6061-T6 billet aluminum, and the fasteners and bolts are from ARP. It includes a high-volume aluminum water pump, and the installation is painless. Our only mistake was thinking the job was going to be difficult, which led us to read the install instructions. Vintage Air has simplified this procedure to the point that you can save a lot of time by simply following the picture diagrams.

Prior to lowering the engine between the framerails, we removed the lower pulley for clearance, installed a set of Prothane urethane motor mounts, and then laid our Hedman ceramic-coated headers in place.

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Once our big-block found its new home, it was apparent the lower pulley wasn't going to clear the front crossmember. We used a cutting wheel and notched a 1x4-inch section. Another necessary modification involved the power-steering pump. Since it's a universal pump, we needed to cut off the plastic return fitting and drill and tap the hole for a 90-degree fitting. This allowed it to clear the upper-control-arm cross-shaft.

Finally, it was time to bolt up the Gearstar 4L60E. But first, we needed to install the Denny's HD driveshaft into the rear-differential yoke. The front of the driveshaft slips into the back of the trans, and the trans is raised to finish the installation. Our new trans does have a slightly larger billet servo on the side, which initially made contact with the trans tunnel. Using a small Dremel attachment, we cut a 2x3-inch notch in the tunnel to accommodate it. We'll need to remove the carpet on the passenger side of the tunnel and re-glass this cut at some point, to keep road noise and heat from entering the interior.

With the engine, trans, and rear diff installations finished, we focused on all the little details necessary to make everything look neat, clean, and professional. We mounted the FAST computer on the inner fender well, and placed the transmission computer in the storage compartment behind the passenger seat. Both are now protected from road damage and rainwater, and still easily accessible if we need to plug in our laptop. The MSD 6 box and coil are mounted on a 1/4-inch aluminum plate and bolted to the firewall right behind the MSD distributor.

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Next, we routed our 1/2-inch fuel line and 3/8-inch return line on the outside of the framerail, behind the rocker cover. Here, they're protected from undercar heat and road scrapes, and are completely hidden from view.

For a little more "bling"—and way better cooling—we installed a Be Cool all-aluminum radiator with twin electric fans.

Once we had everything mounted in the engine compartment, we covered our wiring harness with new GM harness covers. They perfectly match the covers on the FAST E-Z EFI harness and give it a clean, modern look. Last but not least, we bled the brakes, had a four-wheel alignment done, checked for leaks, and reinstalled the original hood, which now boasts a reproduction 427 emblem from Volunteer Vette.


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