About a year ago I tried to clean up the 30 or so holes on my ’59 Chevy Apache. I say tried because I was never was really happy with what I accomplished at the time. I was planning to clean up and fix the uneven, wavy texture I created on my firewall but was not sure how or what to do about it. I could have gone the “shove a bunch of body filler” route, but then I stumbled across a similar truck that had a 3-inch recessed firewall. I had asked the owner how difficult the install was and he said, “If you can halfway use a MIG welder then just about anyone can do it. Have you ever put a puzzle together? It’s something like that, but you have to make some pieces.”
So I started my research on how I could make a recessed firewall out of sheetmetal by visiting my local metal supply house: Industrial Metal Supply (IMS). I then called John Meadows from Deuces Wild Hot Rods & Customs in Fillmore, CA, to get his advice on what size material to get. Since my truck was at John’s shop 100 miles away he could easily measure how big and thick the piece of sheetmetal needed to be. We came to the conclusion that a 16 gauge, 4x5-foot piece of cold rolled sheet of steel would be more that enough material to work with. At the same time John recommended I think about how far I wanted to recess the firewall and how much legroom I was willing to sacrifice by moving the motor back some. We agreed 3 inches back would work just fine.
Besides cleaning up the firewall for looks there are other advantages to pushing your motor back, the big one being shifting the weight of the motor from the front end towards the back. Moving a motor and transmission back 3 inches and down 1 to 3 inches can reduce the weightload the front suspension carries depending on the weight of the motor and moves the mass more towards the rear and center of the vehicle. By moving the motor back and down you will be able to tune some of the understeer out of the front end when hitting corners. This is especially true with trucks that have been converted to big-blocks. With big-block trucks you can have little to no room for the radiator fan. I have seen a lot of cars and trucks that have less than 1⁄8-inch between the radiator and fan. This is not good because all it takes is for you to break a motor mount and the fan will tear up the radiator in a heartbeat.
