In the mid 60's convertible frames were boxed fully along the side rail to provide more strength, due to no car roof missing to provide body support, I agree with jim ss409 on the additional
weight, probably more than 30# were added. The frames being boxed were not only for convertibles, but taxi and police service as well the boxing went all the way from the front end to the
rear


bill in red deer

HonestDave wrote:

---

50torpedo wrote:

---

In the mid 60's convertible frames were boxed fully along the side rail to provide more strength, due to no car roof missing to provide body support, I agree with jim ss409 on the additional
weight, probably more than 30# were added. The frames being boxed were not only for convertibles, but taxi and police service as well the boxing went all the way from the front end to the
rear


bill in red deer

---

 I'm thinking of the X-frames-1961 to 1964. I'm not sure what they would box that isn't already boxed. I'll look over the next few days and check.

---

          They are talking 61-64  they know their stuff       nothing to check  

looks the same as my 61 hardtop frame

427carl wrote:

---

HonestDave wrote:

---

 I'm thinking of the X-frames-1961 to 1964. I'm not sure what they would box that isn't already boxed. I'll look over the next few days and check.

---

          They are talking 61-64  they know their stuff       nothing to check  

---

 I went under the 2 door hardtop and the convertible this afternoon. Had to give the ragtop some hammering to make sure I'm not fixing up a soft frame. I don't see any difference between the two frames. They are both heavily plated in the central section underneath. I know the differences in the 65 and up full size frames, as I've had lots of them, but most of my 64 and under have been non-converts.

It's hard to describe the difference without seeing the two frames side by side.
The convertible frame is almost identical to a regular frame except that it has extra plates added to the top and bottom in a few places. It also has two extra outriggers for the extra body mounts. Another difference is that the bottom plate in the center of the "X" where the center driveshaft pedestal mounts, is much thicker on a convertible frame.

You could use a regular frame on a convertible but it would flex more, and of course, you could use a convertible frame on a regular hardtop.
The stiffer, convertible frames were really popular with the lowrider crowd.

It seems it's hard to tell the difference from underneath unless you know exactly what you're looking for. Most of the strengthening is on top. You've all been a great help, thanks.

Here's a picture of a regular passenger car frame.

 

 Here's one of the pictures that Greaser posted. If you look closely, you can see an extra piece of metal has been added to the top of the frame rail where it goes over the hump.




 There's a similar section of bracing added below the frame up forward of the X and some of the metal in the X portion of the frame is made from heavier gage steel.
My first guess was that the convertible frame might be about 30 lbs heavier. It might not be quite that much but it's somewhere in that ballpark.

-- Edited by jim_ss409 on Thursday 23rd of January 2014 09:43:44 AM