Dry Building: Why It Makes Life Easier

10. With our engine, we found the factory seven-quart oil pan on our Chevrolet Performance 572 wasn’t clearing the crossmember of the AME chassis. We didn’t learn this until our first test-fitting of the engine and trans.

10. With our engine, we found the factory seven-quart oil pan on our Chevrolet Performanc

Test-Fitting
"Sure, test fitting sounds like twice the work. But in today's world of reproduction parts, if all of the manufacturers are to the edge of their tolerances, without dry building before paint, you may find yoruself shimming, cutting, grinding, and even slotting holes to get the proper fit," Jim says as a note of caution.

There are several aspects to this one, from checking fitment on a new chassis going underneath your car to making sure you're A/C unit fits correctly underneath the dash. In the case of the '70 convertible, the Vintage Air climate unit requires two tabs be secured to the firewall for proper mounting. To make sure the unit would be nice and secure, the shop went ahead and welded them to the firewall—something that wouldn't have been possible if the body had already been painted. Then there were the modifications to the firewall for running the A/C and heater lines, requiring further mods to the firewall.

10b. The area circled in the middle photo is where the problem was, and placed next to the solution, an aftermarket Milodon oil pan, shows the difference between the two.

10b. The area circled in the middle photo is where the problem was, and placed next to th

Both of our project cars have had full aftermarket chassis installed in place of the factory originals. For the Chevelle, we had the prototype Art Morrison Enterprises '68-72 A-body chassis. One of the newest pieces out there, the AME unit bolted to the body a bit differently from the factory frame, require some test-fitting and tweaking to get everything just right. Our Fatman Fabrications chassis underneath the '55 has been in production for a few years, so the necessary mods for fitment are listed in the instructions. It still required some small mods for an exact, proper fit, but they were a known quantity.

10c. The Milodon pan cleared with no problems. You could notch the factory pan to clear, but going with the aftermarket part was easier and cheaper in the long run.

10c. The Milodon pan cleared with no problems. You could notch the factory pan to clear,

Checking drivetrain fitment during the dry-build process requires the engine/trans to be installed and removed several times on a custom build. On a painted car, you only want to be installing the engine once, because each time it comes out increases the odds the paint will get nicked. This process also lets you check firewall clearance with the engine. Even though the Chevelle came with a big-block from the factory in '70, throw in our aftermarket chassis that tucks the body in closer to the frame, and you could have issues that require cutting and welding on the firewall.