Re: 1970-1972 Chevelle frame...what will get me bounced?
 

secret :0

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

secret :0

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

you better get ahold of NHRA and ask them FIRST---I see your point but after checking NO HD frame was offered this is the breakdown
Same frame part # for 68-72 --2 dr HT or conv
Tempest
F-85
Chevelle
Skylark--Not Grand Sport or 455 engine

however there are additional braces and mounting points for Conv vs. a HT
I doubt if NHRA checks frames but "if" there are mods you might be in trouble--See if ya can find a Conv from one of the above cars and see if the frame is boxed or a C that will tell ya right off the bat

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

secret :0

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

What does it matter? You can box a "C" frame and whatever else you want to do to your hearts desire. It's no different than running an extra mile of roll bar tubbing. If that's what you think will help, it's OK.
Now lightening the frame would be another matter all together.

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

Now, that's what I need to hear! Thanks Jeff.

I assumed I could do pretty much anything but, until I hear from Travis I won't know...

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

I have a pair of boxed frame sections taken from an El Camino.
Pm me if your interested.
Greg

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

Sorry, but why is it everybody has to get an opinion direct from tech on every issue? NHRA makes a rulebook and it's free. You have to read it, learn it, and follow it. Every little detail can not be put into print. It's a guide that has the most important elements and from there you make the decisions.

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

the convertible frame merely added V shaped boxing sections to the open C channels between the torque boxes. Up through 67, the open C behind the rear wheels was also boxed part way. All body mount areas are on the main frame, nothing added there by the boxing sections. All A body frames were boxed at the front bumper back to the front torque box, and from the rear torque box over the wheels to the body mount area behind the rear wheels, so nothing was added there either by the convertible frame modification. a shorter transmission cross member was used with convertibles because they didn't go into a c section. Up through 67, there were "ears" welded to the inside verticals of the box, and 68-72 the boxing section included a formed perch for the cross member.

Re: 1970-1972 Chevelle frame...what will get me bounced?
 

El Caminos had the convertible frame, but after about 1967 they had a longer wheelbase than the 112" used by 2 door cars. Olds Vista Cruisers had boxed frames, but longer wheelbase. I have heard that the Buick GS's had boxed frames, but haven't checked. That could be why the list above separated them from other cars. Olds offered F35 through 1970. I don't know about other divisions; should be a list of options in the chassis section of the parts manual, at the front.