VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Firewall Holes

Anyone have any pictures of their 1937-1941 engine side firewall that they could post or email me? Just want to make sure I know which hole is for what as there seem to be a lot of holes now the car is stripped bare.

Holes that are pre-punched for things like the heater are complete open holes backed by the inside insulator pad. Pad is original and virgin so I'm surprised the accessory holes penetrate the firewall completely with only the insulator pad keeping the wind out. Is this normal for US models or just a Canadian thing?

Here are some pictures of my 41 firewall. Like you I had numerous extra holes that needed plugging to return it to its original condition. I used patches from a doner firewall to accomplish my repairs. A friend welded in my patches and I and the body shop spent a lot of time making things right.

Good luck, MIke

It was normal for the metal heater hose holes to be punched out of the metal but not the firewall pad for common accessories such as the heater.

Thanks guys. I marked them all pretty well and it looks like there are only a few that I need to patch. There are a lot of holes due to the Chevy/Pontiac thing as I have factory holes and captured nuts for both the Chevy front end parts and the Pontiac front end parts and they don't seem to share any penetrations.

You did a great job cleaning yours up Mike!

Hope this helps. Took it while the engine was out being rebuilt.

MIKE BULLER, excellent save / repair of the firewall. !!!!!!!

mike lynch

Interesting. I have way more holes than Tiny's dash. Thanks Tiny. I thought my unused factory holes were Chevy but GM Canada must have used the same firewall for several model lines. Will have to post some pictures of mine.

There are a number of holes that are there from the factory for accessories that don't really show up will in the photo. I don't really have a good photo showing them. When I added the heater all the holes were already there as well as when I added the radio.

Hi Tim,

I just emailed you 5 pictures from my '37 Master Coupe. I was concerned that the original file sizes were too large to post here. If I compressed them to post here then you could not zoom them to see details.

Picture from my RHD 1940er

Tim, I believe GM Canada took the Chev bodies and modified them for the Pontiac assembly line by adding the holes and threads to mount Pontiac parts. My 39 CDN Pontiac has the Chev firewall with additional holes to mount the Alligator hood support, dual horns, horn relay and eBrake cable. You can see in my photo it has the unused Chev core support rod holes, hood latch and plugged eBrake rod hole. All of the holes for hoses and cables are standard Chev


Mike

Thanks for the pictures guys. Good idea labeling like that Mike - mine are marked with paint pen but think I should do a sketch as it's easy to forget.

I have a lot more holes than every firewall I've seen and most are factory (my under dash pad is in good shape and the holes don't penetrate the pad). There are the holes for the Chevy front end as most people posting have shown me. There are the Canadian Pontiac holes plus there are some others - mostly with weld nuts in the center at the very top so appear to be for a center hood hinge support for something other than Chevy or Pontiac.

Maybe they carried over some firewall detail from previous years? This body is small so can't see them using it for any Buick, Mclaughlin Buick or Oldsmobile models but maybe they just used the same firewall panel across the smaller models so they only had to stamp one. It's interesting to consider.

Tim
Marking the holes as you dismantle everything is good but what happens to the markings when the panel is repaired and repainted?????
Mikes idea with the large markings then the photo is probably the best except with me forgetting the camera and then losing the pic afterwards when I do remember the camera.
Tony

Keep in mind that there are factory holes in the firewall that are intended for options that the owner may or may not install. When I put my radio in I found factory holes where it mounts. I have a Delco with the speaker in the tube box so I didn't have a remote speaker to mount although there are holes to mount one. My point being that unidentified holes are not necessarily not supposed to be there.

LOL - Ya, I took pictures of my markings on the firewall but would like to make a decent physical sketch in case another decade goes by. I have already lost some disassembly pictures due to a failed memory card so I've started taking tons of pics and backing them up. Near the end I figure I'll end up on a plane to Kansas and crawl around Tiny's car with a video camera...

Thanks Tiny, I did forget about the remote speaker but with all the pictures I've seen I think I've got a decent handle on where most options go.
The eye opener for me was having the sun shine through the holes when I was inside the dark car in a dark garage - there are a LOT of holes!

The good thing is I only have about 4 non stock ones to weld up but one looks like they used a chisel rather than a drill....

If it would help I can highlight the various holes in the pictures I sent you while I am looking at the car. It would pretty easy to estimate the size at the same time.

And if you head to Kansas consider routing yourself through Iowa.