How to Mount an A/C Evaporator - 1967 Chevelle
Remember when this project started and I said it was intended to be a car for my wife to hop in and go? That’s still part of the plan. Even after a complete rear sheet metal do-over and a 500+ horse big block, my primary goal is for her to stop hating this car. I’m not sure if ice cold A/C will do that, but I know for sure that the absence of it will make her hate it more.
By now you know that I can’t just leave something alone to work as it was designed and intended to work. Yep, same thing here. Vintage Air builds these kits very specifically and precisely to fit your vehicle. They have a fairly complete set of questions you need to answer before you get to the specific products that will fit your project. They think of everything.
For instance, the engine side, sheet metal, heater box you’ll no longer need once you convert. They supply a black painted sheet metal patch that bolts in to cover the hole in the firewall. Same thing for the old blower fan and motor up in the fender well. That space is repurposed for routing hoses and ac lines. Ingenious. So naturally, I wanted to out-think them and take my own approach to fit up my Surefit system.
The first part of that is the firewall delete plate. Early on, I’d decided that I wanted that job to be done by a GM factory heater delete plate. These were used on vehicles that were ordered for competition use and were not equipped with any kind of heater.
To go one better, since this factory style panel also eliminated the blower motor hole, I decided that it could also take the place of the round, plastic bulkhead V/A supplies to route the A/C lines and heater hoses through. This helps eliminate another sealing surface and gives a clean factory appearance. It also kept me from having to hack a 6” diameter hole in the new delete panel.
I used a hole saw to replicate the size and pattern that best fit into the allotted space on the plate and where it engages with the hole in the firewall behind. I took the grommets intended for the plastic part and installed them in the steel panel instead.
If you see the folly in my thinking already, please hold your comments until everyone else sees it.
On the interior side of the firewall, I went ahead and used the panel that Vintage supplied as it was a firm, smooth mounting surface for the evaporator brackets. The instructions with the kit are very good and are detailed. Each portion of the project is broken out into a smaller subset of directions, hardware, and parts. They tell you what and where to install, regarding hardware. Which I patently ignored on this firewall bracketry. I wanted the black oxide button head bolts to be the only exposed hardware on the engine side of the firewall.
You can’t see them in the photo, but there are four bolts that mount a bracket on the front of the evaporator to the firewall. By design, these bolts are supposed to protrude through the firewall and have a nut installed on the engine side. That’s because the interior side is near impossible to gain access to start nuts on and tighten them. I said “Near Impossible”. I got it handled, thank you very much. The rest of the bracketry was to be sheet metal screwed into the well below the wiper linkage. Not a huge fan of making more holes in areas that will see moisture but they’re easy enough to seal up after installation.
You’ll notice that I’ve added a layer of Boom Mat sound deadening to the bottom side of the dash and kick panel areas. This will help keep vibrations and buzzes to a minimum as the speakers do their work. There will be coverage on that process and some of the steps leading to a finished under dash area.
As the rest of the front of the car comes together, I’ll be able to start connecting systems and components together. This is an exciting time. The more progress I make, the more room I have to work as boxes are emptied and disposed of. Which also makes my garage helper very happy. He likes empty boxes even more than I do!