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X-Frame vs Perimeter Framed Cadillacs

Started by 64\/54Cadillacking, January 30, 2016, 07:49:26 AM

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64\/54Cadillacking

I wanted to ask you all what are your thoughts regarding the differences of the 2 frames, and why did Cadillac claim that the X frame chassis is more rigid than the typical perimeter frame that was generally a standard way for manufacturers to build cars in that time?

Is the X-Frame a more  rigid, a more solid design? Because as wonderful as the late 50's and early 60's Caddies are, many people point out that if they had any weaknesses at all, it s was the X-Frame.

My other question to you guys,  is to the ones that have owned  X-Framed Cads and full-sized Cads that were were built after 64 up until 76, did you notice any differences in how the cars drove? Was one better than the other?

I know Cadillac changed the rear suspension design in 65 to placing the rear coil springs on the axle, instead of the lower rear trailing control arms. They also went from using a singular upper control arm right above center part of the differential with a ball joint type design, to actual separate upper control arms, thus making the Cadillacs a true "4 Link Rear Suspension".

Now if you look at the singular upper control arm with the ball joint, this allows for a much more rotational movement all around. And could be the cause of the serious tail wagger in the rear, but it  also allows the rear suspension to flex more, and to adjust to bad road conditions because the ball joint can move in a 360 degree direction which gives the rear end far greater control in overall movement than  a typical 4 link design.

I also believe this is what contributes to the Cadillac "Float" and that disconnected feeling. I do notice that my 64 feels more marshmallowy in the back compared to previously owned 72, and 68 Deville. Cadillac balanced ride and handling as time went on, maybe because it was getting harder for older folks that bought these cars new to handle them at their old age when your reflexes start to sharply decline.

Currently Rides:
1964 Sedan Deville
1954 Cadillac Fleetwood 60 Special
1979 Lincoln Mark V Cartier Designer Series
2007 Lexus LS 460L (extended wheelbase edition)

Previous Rides:
1987 Brougham D' Elegance
1994 Fleetwood Bro
1972 Sedan Deville
1968 Coupe Deville
1961 Lincoln Continental
1993 Lincoln Town Car Signature Series
1978 Lincoln Continental ( R.I.P.) 1978-2024 😞

66 Eldo

#1
It may be tough to get more than opinions and possibly inaccurate ones at that due to ours cars have suspensions in various states of conditions. They are all old cars too. Subjectivity, coupes vs. convertibles, driving habits and personal tastes also come into play.

I have owned both X-frame and perimeter frame Cadillacs and feel the the perimeter frame models do handle better and offer a more connected feel. I also feel the 69 and 70 models had most of this connectivity or "road feel" and handle the best offering a firm yet smooth ride but not "marshmallowy". I don't know what suspension changes GM made during the 70s Cadillacs but I feel they got progressively softer in slight increments from 71-76. I remember riding in my friends mother's 73 Sedan DeVille back in '82 and to this day I have not been in a smoother riding car.   

I read somewhere that GM promoted the X-frame for its rigidity and having better road isolation offering a quieter ride with less squeaks and rattles. This was a GM statement not Cadillac. The x-frame was also criticized by safety experts as unsafe in side impact collisions.

I have owned a 64 Buick Riviera since '81 and that car has the GM X-frame. It has a great ride but not quite as smooth as either of the Cadillacs frames in discussion. It handles well for a car of its size and better than any Cadillac I have owned. But the only reason I think I feel these differences is because the Riv is 500 lbs lighter and has a shorter wheelbase the the Cadillacs. Its not a better car but it is my favorite of the cars I own.

Speaking of frames. My Studebaker Avanti probably has one of the best for strength and safety. Its a boxed perimeter frame with a heavy x-member welded in the center.   


Scot Minesinger

As an engineer I think the X frame is subject to twisting distortions that the perimeter frame is less vulnerable to.  The side impact is also a factor:  My Grandmother's 1961 Cadillac was T boned when a lady ran the red light in a hurry to get to the eye doctor.  My Grandmothers passenger brake her ankle, and I was surprised when she told me the frame was not bent - now I know why.

For our type of collector car driving, probably either the X frame or perimeter frame are fine.

Likely GM did this partially for economic reasons, as it gets rid of the split drive shaft.  The X frame was re-designed for the 1957 Cadillac Chassis, then after seeing the Chrysler forward look in the fall of 1956, Cadillac had to lower their cars and in 1959 the split drive shaft emerged which allowed the chassis design to remain with minimal modifications.

A strong frame makes a huge difference in the way a car drives.  Here are some pictures of frame strengtheners I added to my four door convertible.  When jacked up right after I bought the car, neither door could be opened.  I replaced all body to frame bushings and then the front door would open but not back when jacked up.  Then I made these frame strengtheners.  They bolt on thru existing holes in the frame, so they can be removed for sake of a purist if they ever own the car.  Designed this on computer with all frame holes aligned with strengthening member.  It is made of 3/16" plate folded to an L.  The vertical section of the L frame goes up 7" between frame and body.  Made a cardboard model, fit it to be sure it was right, then sent the design over the internet to a steel company that laser cut and folded the members.  Drove over there and picked them up. 

After installation the car drove infinitely better.  Half considering installing them on my other two 1970 Cadillacs that already drive wonderful.  Now you can jack the 4 dr Convertible up under the seam between two doors and they both operate perfectly.  There is way less frame flex now.  This was one of L & P's last conversions, and in converting a two door to a four door convertible in late 1969 or early 1970, they did nothing to the frame, which was a mistake.  Although it did make it 104k miles before I got it.
Fairfax Station, VA  22039 (Washington DC Sub)
1970 Cadillac DeVille Convertible
1970 Cadillac Sedan DeVille
1970 four door Convertible w/Cadillac Warranty

64\/54Cadillacking

Interesting points guys. Cadillac actually strengthen up the rocker panels because of the lack of side railings on the X-Frames. I do get a sense of more road disconnection going from my 64, to my 94 Fleetwood, and also my 78 Lincoln Continental.

Now road disconnection doesn't necessarily mean that the car rides better, but that it takes away the effort of driving.

I do notice more squeaks in my 64, I believe the lack of pillars makes the car more prone to flexing. When I go over this certain pothole that is down the street near my house in my 64, the entire force of the impact is transmitted into the cabin pretty badly, almost as if the frame and body aren't doing their job. But going over the same pothole in my 94, and especially my 78 Lincoln, the same forces, aren't felt as strongly in the other cars, the bodies of the 94 and the 78 do a much better job at absorbing the vibration and road shock.

Even though the 64 has a very soft suspension, it doesn't absorb vibrations too well.

I wonder what are some ways to strengthening the X-frame? I might need to take a look at possible broken or missing body mounting bolts on my 64. I know some bushings look pretty squished and need replacing, so that is my next step at trying to make the car ride better.
Currently Rides:
1964 Sedan Deville
1954 Cadillac Fleetwood 60 Special
1979 Lincoln Mark V Cartier Designer Series
2007 Lexus LS 460L (extended wheelbase edition)

Previous Rides:
1987 Brougham D' Elegance
1994 Fleetwood Bro
1972 Sedan Deville
1968 Coupe Deville
1961 Lincoln Continental
1993 Lincoln Town Car Signature Series
1978 Lincoln Continental ( R.I.P.) 1978-2024 😞

Walter Youshock

#4
I have a '57  Coupe deville with the first year X frame and leaf springs.  The car is very easy to drive.  It is responsive yet gobbles up bumps unlike any perimeter framed cadillac I've owned.  Maybe it has something to do with the bias tires.

Like Hendry's book says, on concrete roads, it's a pain.  Every bump hit evenly by the front and rear tire is translated to the center of the X which is under the driver's seat.

My car is the only cadillac I've ever owned that doesn't squeeze or rattle.  I owe a lot of that to the body construction but the frame is also a factor.

Look at the human skeleton.  What is it really...  an X frame.  If you ran girders from your shoulders to your hips and traveled on all fours, do to you think there'd be any advantage?

Also want to add:  years ago, my car was parked next to a friend's '57 Chevy sedan.  As lithe as a '57 chevy looks to people, they couldn't believe the difference between the cars.  Naturally, my car was considerably longer but it was also several inches shorter because of the frame.  Even a '57 Cadillac sedan was lower than its Chevy counterpart.

Both chrysler and lincoln utilized unibody construction.  Cadillac never did (until 1985 anyway). 
CLC #11959 (Life)
1957 Coupe deVille
1991 Brougham

Scot Minesinger

64Caddylacky,

Likely the 64 body to frame bushings need to be replaced.  There should not be rattles.  Also, it is highly likely that the suspension bushings are not in as good of repair as the 1994 Cadillac or 78 Lincoln.

Further, my 1995 Cadillac Fleetwood RWD in 1997 did drive better than my 1970 Cadillac mainly because it was 25 years newer and more advanced.  The 1970 Cadillac (perimeter frame) drives very well, but the 1995 Fleetwood is a little better.

There are posts like this where someone will write that a 72 Cadillac does not drive as well as a 1969 Cadillac, and I think these are related to exclusively to mechanical condition.  I have never driven a Cadillac older than 1966 (assuming 65 is very similar), the 1965 thru 1976 all drive very nice.  Certainly better than my Dad's 2012 Ford Focus.  Also of course the 77 thru 96 RWD Cadillacs drove amazing as well.  Can't wait to drive a CT6 with a V-8!

The way to think about is as you drive your classic Cadillac over a bump or whatever and it was 6 months old would you have accepted the way it performs back in the day.  I think of my Grandmother driving her 64 Cadillac SDV, and rattles over a bump - she would have returned it back to the dealer.
Fairfax Station, VA  22039 (Washington DC Sub)
1970 Cadillac DeVille Convertible
1970 Cadillac Sedan DeVille
1970 four door Convertible w/Cadillac Warranty

Walter Youshock

I've driven low mile '59's and '60's and prefer my '57.  One of the best overall Cadillacs I've ever driven are '62's.  The 66 and 67's I've driven I found sloppy and wandering.  Again, it depends on the example. 

I certainly wouldn't want to be sideswiped in an X frame car.  Oddly, outside of the self starter, it's probably the only feature introduced on Cadillac first that eventually found its way to the rest of the GM line. 
CLC #11959 (Life)
1957 Coupe deVille
1991 Brougham

savemy67

Hello 64CaddieLacky,

If you have the second edition of Hendry's book, look at pages 305 and 310.  The technology available to test the X-frame differed from that available to test the perimeter frame.  Regardless of Cadillac's efforts at testing both types of frames, Cadillac had a reputation to uphold - that of a smooth ride. 

Cadillac was interested in selling a premium car at a premium price while maintaining profitability, so the company was not averse to using what it considered to be engineering innovations if it helped the company achieve its goals.  Many cars of the '30s, 40's, and 50's, both American and foreign, combined boxed perimeter frames with x-bracing.  This is either the best, or worst, of both worlds depending on how you like your car to ride and handle.  There are so many factors contributing to ride quality that I think it is difficult to attribute a qualitative difference to just the type of frame.

I have owned three GM x-framed cars (Impalas) and did a body-off of one, so I can appreciate the construction of the x-frame.  I have also owned four perimeter framed Cadillacs.  To the best of my memory, they all (x and perimeter) drove relatively smoothly.  My most recent comparison is my currently owned '95 Impala SS and my currently owned '67 Sedan DeVille - both with perimeter frames.  The Deville is far and away the smooth ride winner.

Respectfully submitted,
Christopher Winter

Christopher Winter
1967 Sedan DeVille hardtop

Scot Minesinger

Walter,

The chassis and suspensions of the 59-64 are quite similar.  I think you clarified your statement very well stating that it depends on the example, because a 1962 Cadillac really would drive similar to a 1960.  The 1966 and 67 drive great.  Understand that the main difference between a 57or 58 and the 59-64 is the split drive shaft.  Never heard a complaint form someone that owned and X frame Cadillac in good repair that it did not drive well.

I wrote in early post about how important the mechanical condition of the Cadillac is to assess how well it drives.  In fact the reason the former owner sold me the red 1970 Cadillac when I asked "I don't like the way it drives".  With original suspension components, original vacuum hoses, and a carb begging for a rebuild, that is no surprise even after spending 35k on engine rebuild, trans overhaul, brakes, paint top and etc.  Mechanical condition (including body to frame bushings, weather stripping and all rubber parts) is everything on assessing the way a car drives.
Fairfax Station, VA  22039 (Washington DC Sub)
1970 Cadillac DeVille Convertible
1970 Cadillac Sedan DeVille
1970 four door Convertible w/Cadillac Warranty

64\/54Cadillacking

Quote from: savemy67 on January 30, 2016, 09:07:37 PM
Hello 64CaddieLacky,

If you have the second edition of Hendry's book, look at pages 305 and 310.  The technology available to test the X-frame differed from that available to test the perimeter frame.  Regardless of Cadillac's efforts at testing both types of frames, Cadillac had a reputation to uphold - that of a smooth ride. 

Cadillac was interested in selling a premium car at a premium price while maintaining profitability, so the company was not averse to using what it considered to be engineering innovations if it helped the company achieve its goals.  Many cars of the '30s, 40's, and 50's, both American and foreign, combined boxed perimeter frames with x-bracing.  This is either the best, or worst, of both worlds depending on how you like your car to ride and handle.  There are so many factors contributing to ride quality that I think it is difficult to attribute a qualitative difference to just the type of frame.

I have owned three GM x-framed cars (Impalas) and did a body-off of one, so I can appreciate the construction of the x-frame.  I have also owned four perimeter framed Cadillacs.  To the best of my memory, they all (x and perimeter) drove relatively smoothly.  My most recent comparison is my currently owned '95 Impala SS and my currently owned '67 Sedan DeVille - both with perimeter frames.  The Deville is far and away the smooth ride winner.

Respectfully submitted,
Christopher Winter

Hows it going Chris, no I haven't heard of the Hendry's book before. I'll look it up though and give it read!

I always found it strange that Ford fiercely used unit-body construction in the majority of it's cars in the 60's. I heard that the Wixom plant that built Lincolns was tooled for unit-body only, and that the plant didn't have the necessary equipment in order to carry massive frames around. GM far and away had all the resources, and suppliers to provide them the means of building superior cars in the 50's and 60's. By the 70's, Ford realized that the unit-body design wasn't the strongest way to build a car, and it was also very expensive, so they moved onto separate body on frame construction which made life a lot easier for them, and for the cars themselves.

I guess with any framed vehicle, body mounts and it's bushings conditions are crucially  important to how a car rides. I remember I read somewhere online on an old motor trend article that someone interviewed a former Cadillac engineer from the 60's and the interviewer asked the engineer why doesn't Cadillac used any sound deadening material in the trunk or on the underbody of it's cars, and the engineer said"We're not looking to absorb sound, but to isolate it" and by isolating it, it means the frame and body acts like the isolator. So Cadillac's bodies and frames were most likely a lot stronger and heavier duty than say a Chevy Impala. Going from a 3,500lb car to a 5,000lb Cadillac, is a massive difference. So Cadillac used weight, it's suspension layout, and it's frames as a way to isolate passengers from road intrusions that a unit-body car could not match.

So it is good to know some of you have had good experiences with X-Frame Cads and Chevs. I thought maybe my 64 is just poorly constructed or not as tight as it should be, but like I mentioned earlier, I am definitely going to go under there and check for missing body bolts, or anything that doesn't look right. I don't have any suspension squeaks or creaks which is great, but I know the upper control arm bushings need replacing just because of how old the car is.
Currently Rides:
1964 Sedan Deville
1954 Cadillac Fleetwood 60 Special
1979 Lincoln Mark V Cartier Designer Series
2007 Lexus LS 460L (extended wheelbase edition)

Previous Rides:
1987 Brougham D' Elegance
1994 Fleetwood Bro
1972 Sedan Deville
1968 Coupe Deville
1961 Lincoln Continental
1993 Lincoln Town Car Signature Series
1978 Lincoln Continental ( R.I.P.) 1978-2024 😞

Roger Zimmermann

#10
Quote from: Scot Minesinger on January 30, 2016, 09:08:01 PM
Understand that the main difference between a 57or 58 and the 59-64 is the split drive shaft.
Sorry Scot, 57 and 58 have also a split drive shaft. Without it, the rear suspension travel would be almost equal to zero.

The initial question is almost like a comparison between apples to oranges. To compare both chassis types, the body should be of the same design to get some objective results. In the early fifties and before, the body had almost not structural rigidity. The whole assembly was allowed to flex, the idea behind it was to have a better confort. Some went too far like the 1953 Studebaker Starliner which frame was too flexible.
The X-frame (wich was not a GM invention) was a method to lower the cars because with the usual frames, a flat floor was installed on top of it. Another method to lower the body was the Continental Mark II frame which was only suitable for a luxury car: for example, to remove the transmission, the engine had to go out.
The perimeter frame introduced in 1965 was not very strong with open side channels but the way the body was designed did a compensation: windhield and back window were glued to the body, contributing to the rigidity. The body could be lowered because the frame was no more in the way.

Technically a unit-body is more rigid than a body on frame and is lighter. Ford did that for the '58 Lincoln; unfortunately for them, the end result was a very heavy body (and the styling was questionable). Another inconvenient from the unit-body: body changes can only be minor, otherwise the whole structure must be developped again. At a time when frequent body changes was common place, this was a major disadvantage. Some years after, they came back with body on frame...
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Scot Minesinger

Roger,

Very enlightening!  Sorry about mistake on 57 and 58 Cadillac drive shafts.  That even makes it more logical that the 57-64 would drive similarly.  Never thought about how a uni-body made changes to the car more difficult.  That explains the similarity between Thunderbirds 58-60, 61-63, and 64-66 until they went to body on frame in 1967.  I had a 65 and 68 Thunderbird at the same time, both in good repair, growing up in the 1970's and the body on frame 68 drove better than the 65.  That might also be due to suspension improvements.

64Caddylacky,

The condition is everything, and so if your replace all of your body to frame mounts that are not in good repair (if original they need to be replaced) and make sure your suspension is all in good repair, you should love the way your 1964 Cadillac drives.  Some things these cars accomplish are unmatched today, for example the climate control is better in my 1970 than a modern car, because it is quieter and more comfortable.  Further a 129" wheel base cannot be substituted and the ride is also unmatched by a modern car too.  Replacing these bushings is a different operation than the 65 and newer Cadillacs.
Fairfax Station, VA  22039 (Washington DC Sub)
1970 Cadillac DeVille Convertible
1970 Cadillac Sedan DeVille
1970 four door Convertible w/Cadillac Warranty

64\/54Cadillacking

Quote from: Scot Minesinger on January 31, 2016, 08:56:39 AM
Roger,

Very enlightening!  Sorry about mistake on 57 and 58 Cadillac drive shafts.  That even makes it more logical that the 57-64 would drive similarly.  Never thought about how a uni-body made changes to the car more difficult.  That explains the similarity between Thunderbirds 58-60, 61-63, and 64-66 until they went to body on frame in 1967.  I had a 65 and 68 Thunderbird at the same time, both in good repair, growing up in the 1970's and the body on frame 68 drove better than the 65.  That might also be due to suspension improvements.

64Caddylacky,

The condition is everything, and so if your replace all of your body to frame mounts that are not in good repair (if original they need to be replaced) and make sure your suspension is all in good repair, you should love the way your 1964 Cadillac drives.  Some things these cars accomplish are unmatched today, for example the climate control is better in my 1970 than a modern car, because it is quieter and more comfortable.  Further a 129" wheel base cannot be substituted and the ride is also unmatched by a modern car too.  Replacing these bushings is a different operation than the 65 and newer Cadillacs.

Thanks Scot! Yeah I'm sure if I replaced the frame mounts, or most of them for that matter, it will make a huge improvement in how the car rides. I read on another forum that someone that owns a 63 Cadillac jacked up the car on the body instead of the frame rail, and broke off one of the body mount bolts. After losing that bolt, he said that the car rode terrible, and lost it's rigidity. But once he replaced it, it rode great again. So it's pretty clear how important frame mounts are, and how they can make or break a cars solidarity. And yes the huge wheelbase on our cars gives the feeling like the car is gliding down the freeway with Aladin underneath it. ;D Shoot, not even the extended wheelbase S-Class or 7-Series has a 130 inch wheelbase

The X-Frame Cads also seem to ride lower to the ground than the later Cads. It's really odd because when driving my 64, although it's low to the ground, you feel as if you are off the ground while sitting inside the car because how steep the front seats recline.

They simply don't make luxury cars like these anymore unfortunately. All the luxury cars today are all about rode feel, and increased handling. Automakers will never be able to achieve that same kind of total isolation from the ground below you in a way like our old Cadillacs do. The feeling going from a newer unit-body luxury car, to an old body on frame Cad feels very different. I personally like the old feel of the Cadillacs and the ease of operation. Screw the CTS, SRX, and the likes for their sporty nature (No offense). Luxury cars should be all about comfort, silence, and the total elimination of any effort to drive the car. Let the car do the work for you. 8)
Currently Rides:
1964 Sedan Deville
1954 Cadillac Fleetwood 60 Special
1979 Lincoln Mark V Cartier Designer Series
2007 Lexus LS 460L (extended wheelbase edition)

Previous Rides:
1987 Brougham D' Elegance
1994 Fleetwood Bro
1972 Sedan Deville
1968 Coupe Deville
1961 Lincoln Continental
1993 Lincoln Town Car Signature Series
1978 Lincoln Continental ( R.I.P.) 1978-2024 😞

savemy67

Hello 64CaddieLacky,

"Cadillac Standard of the World The Complete History"
Maurice D. Hendry
second edition published by Princeton Publishing, Princeton NJ
copyright 1977, 1973
ISBN 0-915038-08-0 (Princeton Publishing), ISBN 0-525-07299-3 (E.P. Dutton, distributors)

Hello Roger,

In a previous post to this thread you mentioned that "...The perimeter frame introduced in 1965 was not very strong with open side channels but the way the body was designed did a compensation: windhield and back window were glued to the body, contributing to the rigidity. The body could be lowered because the frame was no more in the way."

I happened to be underneath my '67 today, and verified that the frame is fully boxed - there are no open side channels.  I checked the '65 Data Book from the GM Heritage Center and it appears that the newly introduced (in '65) perimeter frame was also fully boxed.  Additionally, within the boxed section of the perimeter frame, bulkheads were welded in giving the frame section enormous torsional rigidity.

Rocker/sill step-over height was lowered about one inch with the perimeter frame design.

Respectfully submitted,
Christopher Winter
Christopher Winter
1967 Sedan DeVille hardtop

Roger Zimmermann

Oups Christopher, you are right! Sure, I mixed something...The book from Roy Schneider, Cadillacs of the sixties, has a nice picture and description; the frame is boxed...
A study/testing with 2 new frames, a X-frame and a perimeter one could tell which one is more robust.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

bill06447

In my younger days, I would bring cars to the demolition derby. One time I brought a 64 Chevrolet and the first hit from the side was a sobering reminder of why X-frame cars were few and far between in these events. It's a wonder I made it out in one piece; the first hit pushed the passenger door and floor clear over to the center of the car. Never had that experience with perimeter framed cars.

Bill

64\/54Cadillacking

Quote from: bill06447 on February 01, 2016, 10:02:50 PM
In my younger days, I would bring cars to the demolition derby. One time I brought a 64 Chevrolet and the first hit from the side was a sobering reminder of why X-frame cars were few and far between in these events. It's a wonder I made it out in one piece; the first hit pushed the passenger door and floor clear over to the center of the car. Never had that experience with perimeter framed cars.

Bill

Most of the demo derby guys preferred full-size GM makes of the 70's, same goes for 70 Fords. In the 60's, it was the big 60's Imperials up unto 65 I believe, and just about any 60's Lincoln Continental because of their heavy curb weight combined with their extremely solid body construction, and bank vault like doors to help in side protection. I should know because I owned a 61 Lincoln, and those things are TANKS ON WHEELS. Probably the only car I have ever owned that literally felt like the car was meant to be bulletproof because of how heavy and solid the doors felt. It took effort opening up the doors, especially the rears. I will say the Lincoln definitely felt more solid and tightly constructed than my 64 Cadillac.

I am sure  an X-Frame Cadillac would hold up a lot better than a X-Frame Chevy in a derby like that. A 64 Impala weighed only 3,500lbs, while a 64 Cadillac weighed around 5,000lbs. That's a huge difference in weight which matters in a demo derby. Having an extremely long hood and trunk like the 70's Cadillac in derbies allows for more damage to occur until the body is no more. Smaller cars simply don't have enough metal to sustain the impacts like the big ones do.

But I hear you on the X-Frame part, the side impact protection is a problem. GM sorta went backwards in 58 going from the perimeter frame in 57, to the X-Frame in 58 on the Chebbys and Caddies.
Currently Rides:
1964 Sedan Deville
1954 Cadillac Fleetwood 60 Special
1979 Lincoln Mark V Cartier Designer Series
2007 Lexus LS 460L (extended wheelbase edition)

Previous Rides:
1987 Brougham D' Elegance
1994 Fleetwood Bro
1972 Sedan Deville
1968 Coupe Deville
1961 Lincoln Continental
1993 Lincoln Town Car Signature Series
1978 Lincoln Continental ( R.I.P.) 1978-2024 😞

66 Eldo

Quote from: 64CaddieLacky on February 01, 2016, 10:33:36 PM
Most of the demo derby guys preferred full-size GM makes of the 70's, same goes for 70 Fords. In the 60's, it was the big 60's Imperials up unto 65 I believe, and just about any 60's Lincoln Continental because of their heavy curb weight combined with their extremely solid body construction, and bank vault like doors to help in side protection. I should know because I owned a 61 Lincoln, and those things are TANKS ON WHEELS. Probably the only car I have ever owned that literally felt like the car was meant to be bulletproof because of how heavy and solid the doors felt. It took effort opening up the doors, especially the rears. I will say the Lincoln definitely felt more solid and tightly constructed than my 64 Cadillac.

The 60s Lincolns were unibody construction which provides better road isolation and even on a car that big a more solid feel than a body on frame vehicle. I have owned at least 6 of them and know what you are saying.

I am sure  an X-Frame Cadillac would hold up a lot better than a X-Frame Chevy in a derby like that. A 64 Impala weighed only 3,500lbs, while a 64 Cadillac weighed around 5,000lbs. That's a huge difference in weight which matters in a demo derby. Having an extremely long hood and trunk like the 70's Cadillac in derbies allows for more damage to occur until the body is no more. Smaller cars simply don't have enough metal to sustain the impacts like the big ones do.

But I hear you on the X-Frame part, the side impact protection is a problem. GM sorta went backwards in 58 going from the perimeter frame in 57, to the X-Frame in 58 on the Chebbys and Caddies.

J. Skelly

Scot,

"A strong frame makes a huge difference in the way a car drives.  Here are some pictures of frame strengtheners I added to my four door convertible.  When jacked up right after I bought the car, neither door could be opened.  I replaced all body to frame bushings and then the front door would open but not back when jacked up.  Then I made these frame strengtheners.  They bolt on thru existing holes in the frame, so they can be removed for sake of a purist if they ever own the car.  Designed this on computer with all frame holes aligned with strengthening member.  It is made of 3/16" plate folded to an L.  The vertical section of the L frame goes up 7" between frame and body.  Made a cardboard model, fit it to be sure it was right, then sent the design over the internet to a steel company that laser cut and folded the members.  Drove over there and picked them up."

If you don't mind, who made the laser cuts for you?  I'm thinking of doing that to replace the cheap plastic center armrest hinges used on my '68 Eldorado front seat.

Thanks.
Jim
 
Jim Skelly, CLC #15958
1968 Eldorado
1977 Eldorado Biarritz
1971 Eldorado (RIP)

Ratfink11

Hi all,
is there anyone selling the frame reinforcement plates?  or do they need to be made?

Thanks