De-butchering the firewall

[snailwagon]

This December, I get a couple of weeks of semi-free time, so I am going to dedicate it to getting one of my 55's in shape. The subject has been parked for 22 years and is rust free. However, the firewall has been butchered all to s*** for a 350 swap. I am going to go with an sbc because of cost, availablility, and ease of finding one with smog equipment (California, I'm going with legal smog). Also, it already has a new clutch, the AA adapters, sbc exhaust, starter, wiring, etc.. As much as I like F/2F's, they do not suffice for a 5500lb vehicle that will mostly be a street machine. They suit me much better for actual wheeling (for a trail rig, I'd prefer a 2F and gearing).

I assume the butcher job was for distributor clearance. however, I have never payed much attention to sbc swaps and don't know much about them. My question is can I move the firewall back to the near stock location, or should I keep it set back similar to its current position. This is my first step in this project and I will not have an engine for a month or two to check placement. I am fully ready to have to assemble the drivetrain and then cut the mounts and reweld them in the proper positions, if they are not already.

So in reconstructing the firewall, should I strive for near stock dimensions? It needs to go forward a little bit for all my heater/ AC stuff to line up properly.

 

[snailwagon]

I have to get a little closer to it and have it all dissasembled, but I am going to a) just use steel sheet and have a friend brake it and go with an angular firewall, b) combine the front hump/lower cowl from a 40 with some sheet metal, or c) talk the local junkyard nazi's into selling me the front cowl of a 55 (they don't let you pull parts off yourself and have a 55 and a couple of 40's pretty complete)

 

[usmcruiser]

You should send Ige (Nuclearlemon) a PM and ask her for pics. She has a 350 in her piggie. It isnt runnning but it is burned in.,

 

[inkpot]

Howdy! I dropped a 77 350 with the large distributor into my Piggy without any changes to the firewall. The dizzy would be up close to the heat control valve it the engine was positioned way, way back, for some reason. Your rig looks like someone planned on a Big Block. Several inches longer and wider, and much more complicated to fit in a Piggy. Mine is smog legal, with all the original stuff. Phoenix is just about as picky as California on smog. I assembled my entire driveline and used a big tranny jack and an engine picker to slide it into, and our of my rig to figure out placement, and then weld in mounts. I also have the original Saginaw PS system that was on the donor car. It is mounted behind the radiator, invisible from the outside. John

 

[Wayneraintree]

350 should fit without firewall modification

Here is a picture of the 350 in mine. Mine is a 93' TBI 350.

Let me know what pictures you would like to see and I can take them. I can also measure the mount's distance from some specified point on the 55. I run a saginaw box from an astro van and it mounts inside the frame behind the radiator. There are more pics here.

 

[snailwagon]

I really have no clue what the intention of the original owner was. In the back of the truck was the proper clutch, some vortec heads, and some more identical motor mounts. It has the sbc advanced adapter bellhousing and the tranny is in the same location as stock.

After staring at it awhile this afternoon, I am probably just going to repair the firewall to about the same dimensions it used to be and not worry about engine clearance.
I might just end up using a 302 I have. It is clean, great even compression and runs nicely. I have never driven it but it starts fine and has good compression numbers. Upon closer inspection today I pulled the numbers and it is one of these "mexican 302" blocks, I think from 1969. I think it has cleveland heads also. The previous owner of the cruiser that the 302 was in had the cruiser about 2 years before he wrecked it. He didn't know anything about the motor besides it was fast. Enough rambling on.

 

[cruiser88]

man thats a butch job

 

[snailwagon]

My favorite part is the 20 year old, pop-riveted tecate beer sign used for a firewall. At least this is a relative easy fix, especially with the drivetrain removed. Out of the whole mess, the hardest part will be cleaning up and cutting out all the old s***. I really hate lying on the floorboard when wrenching.
I'll post a pic up of the finished product in this thread once I'm done.