I am building my first hot rod and bought a stock, mostly complete, '31 Ford Sedan as the platform. This build has to be INEXPENSIVE as possible. I've been gathering parts and so far I have an engine, tranny, drive shaft, rear end, bias-ply tires with rims, one cross member, and a dropped axle with drum brakes and suspension. With all of that being said, here's the question... if I box MY frame, will it be able to handle 300hp? The stock frame is in very good shape. Analyzing the cost, one option is Speedway. They sell a box tube frame you weld together yourself for $1000. The kit also included a bunch of other parts I will need to put this whole thing together. A second option is to box my frame by buying and using the pre-cut pieces for $200. Even with buying all of the other parts piecemeal, I believe it will be much cheaper than the first option. The third option is I buy 2x3 and build the frame from scratch, but I'm assuming that is way above my ability level. Any and all thoughts are welcome!! Thanks in advance!!
Depends on the intended use of your car, yes, generally you could just box the frame, install an x member to stiffen it. If you're gonna abuse it by heavy use like drag racing, spend some money. For a street car, pay attention to the details, make it strong as you can, lots of model A's running around with reinforced stock frames.
When I first started doing customer chassis, reproduction A rails were not available but good stock A frames were. I simply went to the butcher shop and got a length of paper and made a pattern of the inside edge of the stock frame and went to the local sheet metal shop and had them shear some 10 gauge plates to match my template. I welded them into the A frame keeping the front and rear cross members. Was cheap and worked for many years until I started using repro A perimeters.
me too. First thing to do is get the body off the frame and find out if it is bent. Some A's led a hard life on rural roads and can be bent down at the front of the firewall. Some have the front rails from firewall forward, bent off to one side. If that is addressed, then box it and it will be fine. An X center is best if it was a roadster, and is still a plus with a sedan if you want one. When boxing, don't grind off too much of the welds, or some builders set the boxing plates a bit into the rails to not have to grind and weaken the welds.
The last A frame I did was fully boxed and I used the X from Dagel’s. It worked out great. Your first post says you already have the engine, trans, and rear end, what do you have? Sent from my iPhone using The H.A.M.B. mobile app
I got another A frame cheap at a salvage yard and used it to box mine. Right rail slid into left rail and left rail slid into right rail. Easy pie cut on donor rails at taper and clamp it tight. Frame holes even lined up with each other
before you weld, check your frame for "sag" at the stock tranny mount / firewall area... it will pooch your hood to cowl and grill to hood gaps...
This car is built on a boxed T frame. Drives 200+ miles one way to race and is now running 10s. It handled 400+ ponies for at least 7 years and is now holding up under 600+. Maybe I got my head in the clouds but I have an idea that your A frame with boxed with handle 300 horses just fine.
As sloppy suggests, before you do any boxing, make sure the frame is level and true. I purchased my first Model A in 1970 and had several since. Model A frames are notorious for sagging especially the 20" from the driver side, rear motor mount to the middle crossmember. There is zero support in this area and it held the heavy battery and drivers weight. One frame I had had a 1/2" sag in this area. You also might consider welding the riveted in crossmembers. As others have suggested an X member with drop out rear trans mount will add considerable strength.
I bought my model A in 1998,from a buddy who had it for years before that,who bought it from somebody else. It had a SBC turbo 350 and an olds rear.It had been drag raced a little.When going in driveways the shifter would move alot.It was unboxed,tore it down last year to box it and changed it from a auto to a stick and install the QC.We made our own boxing plates,it was a buggy spring car front and rear,it will now be coil over in the rear.
A buddy of mine down the street is replacing his banger with a 8BA in his A 5 window. He bought his boxing plates from a guy on here with holes and dimples in them, laid his frame out flat on a couple of steel girders, clamped it down and boxed it up nice and tight. Excellent job in my opinion. I like the idea personally of the dimpled holes so you can access bolts and what have you but I would run them slightly inboard of the frame like someone mentioned above. I like the look and you won't be tempted to overgrind the welds. I'd leave enough room to run the fuel line and brake lines between the frame edge and boxing plates. Just an aesthetics thing.
I've boxed several original Model A frames and they have been able to stand up whatever was powering the cars. HRP
When I was a young man we always boxed them with the plates slightly inboard so that we would run fuel lines brake lines and ect. Maybe it was a regional thing. We never welded them up solid either we always skip welded them. I think that difference between us and the newer builders is that we came from an era that considered a boxed frame more then strong enough. The modern builder seems to want to over engineer things.
I know this isn't the forum for this type of hot rod, but it's a SBC from the 60's with 3 deuces on top and a cam, a turbo 350 (with shit kit).
Well the transmission may not be considered to be traditional but an early SBC with 3 deuces is traditional enough. Unless of course you buy into the whole belly button flathead deal. LOL
Assuming the original frame is in good shape to start with, I would trust a properly boxed original Model A frame over any Speedway kit frame or homemade box tubing frame.
My Swedish grandfather on building things for others: If you make it twice as strong as it needs to be, it might last half as long as it should.
Personally I'd box it and add a decent K or X member as it'll take the majority of the torsional flex out of frame and the body. It'll drive and handle better as well as providing a good solid foundation. Sent from my SM-G950F using The H.A.M.B. mobile app
The vehicle serial number is stamped on the top of the frame rail, I think just behind the firewall body mount/ You might want to locate that and take care to preserve it. If your car's titled currently, compare the ID number on the title with both the frame number and the engine number and see if any of them match. Step 1) If the number on the engine matches the title, before you make any mods or dispose of the engine, do what is necessary to legally change the title number to match the frame number. Step 2) If none of the three numbers match, see Step 1)...... Step 3) If the title and frame number match.....proceed as planned and consider yourself damn Lucky!
That is the same thinking that caused Harley Davidson to become so big and bulky. Anything that broke at 1" became 2". There is actually a very fine line that separates over engineered from under engineered, its not like walking a tight rope more like walking a slack rope. Balance is required to keep it all in perspective.
The body is off the frame. I've been putting in patch panels, some store bought, some home made. I want the get the chassis together so I can be ready to drive it then get the body back on, chop the roof, and channel it.
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