The Stovebolt Site Forums The Shop Area The HiPo Shop boxing the frame

I need some input, I have a 1951 chevy 3100. I plan on running a 388 SBC with a 700r4 transmission. I will also have a TCI front suspension on the front. I have been considering boxing in the frame, is this neccessary, the frame appears to be somewhat weak. I have the material to box in the frome from front to rear. Anyone have any input on this? thanks

Considering you're running a 388 I assume you might be "getting it on" so to speak. Also considering you have the steel and the welder and the ability to weld, I would say, it you have the time, go for it. Besides it sure looks good.

AS stated, if you plan on getting it on, you absolutely have to strengthen the frame. It won't break, but you will twist it with the torque you'll be putting down. p.s. how did you get 388 c.i.? I thought the stroker 350 was a 383 ?

Didn't Rambler make a 388?

Tim K, 350 block bored 60 with a 400 crankshaft is a 388, bored 30, 383

Just posted this on another topic. I just bought "How to Build Hot Rod Chassis" by Tex Smith, $23.

Chevy truck frames are basically same deal (in fact he covers putting a front clip on one) as rest of the stuff he covers. See that for more info.

The stock 3100 frame is 10 gauge. contact your local sheet metal guy, and have him sheer off a few strips. The fire up the welder.......a few hours later, fire up the grinder.......a few hours later add paint.

I am in the same boat with a BB Olds.

That TCI frontend should have some metal to box in the frame where IT mounts. Boxing the frame can be a bear you have to mount all your tubing on the outside of IT.

I have the frame on my 40 ford boxed. IT does look nice when finished.

R

I would think you could run tubing inside the box if you planned it out in advance and left an opening where needed.

G'Day Tony,
It is law here to box ALL of our chassis rails as part of registration.
The hardest part is making sure that you plan well ahead to ensure that you have all your fuel/brake lines, electrical wiring and captive bolts in place BEFORE boxing the chassis rails.
It's really hard to get all this sorted once the rails are boxed.
Once that is done, the boxing is quite a straight forward process.
A real handy tip is to use strips of cardboard cut out to the exact shape of the frame rail, trace them onto your sheet steel and then cut out the boxing plates to the right shape.

Good luck....Doc.

Because of the weight of the motor and the power. It WILL twist the frame the first time you punch it. If you box YOU MUST bod From the front of the arm Mounting point to the rear leaf Mounts. You will also, want a cross over bracing. Like an X frame.

Depending when the book was made. The tecnologies today require the X Frame support. It is by far safer. I do not recomend installing any wires or tubing like brake lines inside your future inclosed frame as stated in another post. If there is leaks or a short in the wires. You will have a hard time. Plus if they are installed before you box the frame. YOU may very well have issues with the heat doing damage to the wires etc.

Good luck

Building a solid box just adds more weight than is necessary. The same strengthening effect can be had by cutting large ovals into the plates you add before they are welded in, leaving an inch or so on the top and bottom to add the necessary stiffening. it's a trick I learned long ago when beefing up dirt tracker frames. The box section adds the strength, and the cutouts allow weight to be concentrated where it's needed instead of just making the thing a lead sled. To make the cutouts uniform, use a large hole saw to form the ends of the slot, and join them with a straight cut with a sawzall.

The cutouts also solve the problem of making the channel area inaccessible for tubes, etc.
Jerry

Jerry has just the same thought i have. box it w/ holes as the mid section is from the factory. in other words keep the structural integrity of the box but have the steel company or you plasma cut holes triangles or ovals in the box before you weld it all up. you would have access inside the box for wiring, fuel and brake lines. some steel shops can do this work for you as in small job production.
my fairly local one does big and small jobs. and in this economy many more may also job it for you.
http://www.sk-steel.com/

Because of the weight of the motor

The small block weighs less than the original L6.