66 Impala Super Sport Chassis/Frame - Impala Tech
Convertibles Convertible Q&A's

  • 1 Post By jayoldschool
  • 2 Post By Big Dave
  • 1 Post By RMC1218
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post #1 of 7 (permalink) Old 09-11-2020, 10:24 PM Thread Starter
Join Date: Aug 2017
Location: Outside Chicago
Posts: 36
66 Impala Super Sport Chassis/Frame

Hey All,
I have a 1966 Impala SS convertible, 396CID, Automatic (from a 68 truck). I suspect the frame was changed because
1. There were clutch pedal brackets bolted to the frame below the master cyl.
2. While installing the Body mounts the frame did not have the mounting holes under the center of the doors. (I had to drill them).
3. While driving it feels like it flexes allot. Or this maybe the way they were back then?

The floors have been replaced so I cannot tell by the shifter access location.

I'm afraid it has a coupe or 4 door frame. How can I tell if it has the correct frame?

I also would love to know what engine & trans it came with.

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post #2 of 7 (permalink) Old 09-12-2020, 10:29 AM
Join Date: Jul 2009
Location: Canada
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The convertible frame has extra boxing and supports. Check the Chassis Service Manual, there are likely specs and photos for the differences. Probably found on Google Images as well.
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Two doors, four doors, wagons, and ragtops.
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post #3 of 7 (permalink) Old 09-12-2020, 10:31 AM
Join Date: Jan 2006
Posts: 13,019
Convertible got it's own frame that was stamped from a heavier gauge of metal and drawn deeper for a additional strength. this was used not because GM liked spending money on materials but because with the doors open the only thing keeping the car from breaking in half is the frame (a hard top is a big architectural arch connecting the the front and the back to add strength).

If your frame is original you can read the "hidden" VIN stamped on top of the frame behind the passenger side rear wheel. You will need an inspection mirror to do this while lying upside dow and getting all of the sand and road grime off the top of the frame in your face as you look for the numbers. Please wear safety goggles as a friend of mine went blind doing this (it was how I inherited his 1958 Corvette project).

Big Dave
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post #4 of 7 (permalink) Old 09-13-2020, 11:10 PM
Join Date: Jan 2014
Location: CenTex
Posts: 37
according to my Hollander's 39th edition, the '66 convertible had a frame that was shared with no other vehicle or year. as Big Dave pointed out, it will be a boxed frame.

when I had to replace the tranny cross-member on my '67 convertible in the early '90s (x-member was rusting out), it dropped into pockets that had been welded on the frame. however I had to use a x-member from a hardtop which was wider. I know this because I actually pulled mine from an open frame in the junkyard with no body shell on it. My recollection is that that frame was not boxed and simply had holes drilled in the frame for bolting the x-member down. All the curves in the x-member were in the correct place, the x-member was simply an inch or two wider on each end. I clamped it flat in a vise, trimmed the ends, drilled new holes in the x-member ends and dropped it in.

I mention all this as to give you a reference point. Unfortunately, as Dave pointed out, the only real way to be sure is to look for the hidden VIN stamped on the frame. according to a thread I found on chevytalk forum (chevytalk.org/fusionbb/showtopic.php?tid/343316), my hidden VIN is located on the driverside frame top. some people even said they did body off inspection and found no stamping whatsoever. take it for what it's worth,let us know if you find the VIN frame stamp.

if you need some visual references, try searching on Google for the following string "1966 chevrolet passenger vehicle hidden vin" and click on the images category after getting search results

Last edited by 65_&_67_Impala; 09-14-2020 at 02:25 PM.
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post #5 of 7 (permalink) Old 09-14-2020, 07:28 AM
Join Date: Aug 2020
Location: Tampa, FL
Posts: 47
"1966 chevrolet passenger vehicle hidden vin"
It generated many results, but you were right. It is indeed a boxed frame.
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post #6 of 7 (permalink) Old 09-16-2020, 11:08 PM
Join Date: Aug 2008
Location: Miamisburg, Oh.
Posts: 3,342
Blog Entries: 15
if you need pics of a 66 vert frame I can take some for you.

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post #7 of 7 (permalink) Old Today, 04:58 PM Thread Starter
Join Date: Aug 2017
Location: Outside Chicago
Posts: 36
FYI - third response!!

Yes PICS would be appreciated
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chassis, frame

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