Everything you always wanted to know about GM's "X" frames :

[Greg Myers]

All right here class, today's lesson, GM's famous "X" frame. http://www.curbsideclassic.com/automotive-histories/automotive-history-an-x-ray-look-at-gms-x-frame-1957-1970/

Take notes. There will be a quiz tomorrow.

Edited March 17, 2014 by Greg Myers

[Ace-Garageguy]

Great tech link, Greg. Thanks.

[Greg Myers]

Did you know these frames required special headers to connect with the stock exhaust ? and you wont find them in any kit.

Edited March 17, 2014 by Greg Myers

[TooOld]

Great link , thanks for sharing it !

And yes , I bought a set of Blackjack headers for my '60 that were similar to those , I copied them on my model .

Edited March 17, 2014 by TooOld

[Greg Myers]

So how'd you do that? I had a '60 El Camino 283, four speed, three twos, and those headers. plugged em into the stock exhaust first, then a set of side pipes. worked really well.

[Austin T]

Just out of curiosity how well did these frames fare in collisions? I want to say I remember Lotus had a similar type frame (A Y frame?) that was infamous for killing drivers in hard collisions.

[Art Anderson]

Just out of curiosity how well did these frames fare in collisions? I want to say I remember Lotus had a similar type frame (A Y frame?) that was infamous for killing drivers in hard collisions.

Head-on, or rear ended, they did as well (or as poorly) as anyone else's "ladder frames". There was a lot of concern back in the day as to side impacts, due to there being no frame rails outboard of the center of the frame--but then most other cars having full ladder frames suffered badly in side impacts, up to and including "wrapping around a utility pole or tree trunk).

From a torsional standpoint, the GM X-frames were noticeably stiffer against "twisting" than any other contemporary frame, due to the center spine acting as a "torque box"--that structure was incredibly stout.

Art

[62rebel]

triumph heralds/spitfires/gt6's have a scaled-down version of this frame.

I sense a lot of worry over how older cars fared in collisions.... no better or worse in their time than modern cars. certain design features that eventually became obviously dangerous were modified, like collapsible steering columns, fixed rear-view mirrors, plain steel dashes..... but it's ALWAYS been safer when buckled up properly and aware of your surroundings. people have always and will continue to drive well past their AND their car's limitations, and there is nothing that can be added to a car to negate the stupidity of the operator.

[Longbox55]

Just out of curiosity how well did these frames fare in collisions? I want to say I remember Lotus had a similar type frame (A Y frame?) that was infamous for killing drivers in hard collisions.

http://youtu.be/joMK1WZjP7g

[Ace-Garageguy]

Just out of curiosity how well did these frames fare in collisions? I want to say I remember Lotus had a similar type frame (A Y frame?) that was infamous for killing drivers in hard collisions.

It's prudent to remember that the Lotus Elan and Europa had very light fiberglass bodies, and NO appreciable structure other than the frames themselves. While the light bodies contributed significant rigidity when bolted on (much like an egg shell is rather stiff) they also contributed very little to occupant protection.

The large GM cars with steel bodies had considerably more crush-resistance and occupant protection than the Loti.

But I do SO WISH that more focus would be put on drivers actually being trained to be competent to AVOID COLLISIONS, rather than trying to make road vehicles idiot-proof and remove any thought of safe operating practices and personal responsibility from consumers' minds.

A Lotus NEVER killed a driver. A DRIVER'S INCOMPETENCE or CARELESSNESS was the killer.

Edited March 18, 2014 by Ace-Garageguy

[Greg Myers]

and this http://www.youtube.com/watch?v=w6jo6gVug48

Edited March 18, 2014 by Greg Myers

[Greg Myers]

http://youtu.be/joMK1WZjP7g

This was all covered in the original post.

The ’59 Chevy became famous in 2009 when it was crashed into a new Malibu, and (not surprisingly) fared rather poorly. The X frame probably played a relatively small part in that, given all the other aspects that were so different between these cars. And who knows how rusty the Chevy frame and/or body were. Speaking of, the X-frame is rather notorious for rusting, and there is a pretty brisk business in replacement frames, often reinforced. One wouldn’t want to start throwing a Chevy low-rider hydraulically four feet into the air with a rusty frame.

Edited March 18, 2014 by Greg Myers

[Greg Myers]

[slusher]

http://youtu.be/joMK1WZjP7g

Did you see the rust fly out in this video on impact.

[Chas SCR]

Did you also know that the X frame was in the pontiacs before it was in the Chevy line. Chevy in the 40s was using the box or squar frame up to 58 and then came back in 65. But it was Pontiac that had it in there line.

[Art Anderson]

Did you also know that the X frame was in the pontiacs before it was in the Chevy line. Chevy in the 40s was using the box or squar frame up to 58 and then came back in 65. But it was Pontiac that had it in there line.

"X" as in the "hourglass" shaped frame, which was pioneered at Cadillac in 1957, or "X" as in an X-shaped crossmember? If the latter, that was first used on the 1929 Cord L-29 front drive chassis, to eliminate chassis "twisting".

Art

[Danno]

Is this what is referred to as an X-rated topic?

[Greg Myers]

X-actly

[Lovefordgalaxie]

Did you see the rust fly out in this video on impact.

Saw that video lot's of times, and I can say the 1959 Chevrolet was sabotaged. The way the car behaved compared to some actual road crashes with similar cars lend to the conclusion that the car had no engine, just the absolute minimum fender bolts to keep the parts on the car, and the frame was weakened by carefully done cuts.

In other hands, the video is fake, just made to promote the new Malibu, and paid for.

Who has doubts about that, it was done before.

Volvo did the same on a TV commercial years ago. They reinforced a Volvo SW so it would survive being run over by a Big Foot truck.

The difference is that Volvo was caught, and it was all over the magazines and the news.

[Art Anderson]

Saw that video lot's of times, and I can say the 1959 Chevrolet was sabotaged. The way the car behaved compared to some actual road crashes with similar cars lend to the conclusion that the car had no engine, just the absolute minimum fender bolts to keep the parts on the car, and the frame was weakened by carefully done cuts.

In other hands, the video is fake, just made to promote the new Malibu, and paid for.

Who has doubts about that, it was done before.

Volvo did the same on a TV commercial years ago. They reinforced a Volvo SW so it would survive being run over by a Big Foot truck.

The difference is that Volvo was caught, and it was all over the magazines and the news.

Having grown up in the 1950's, taking Driver's Education in a '59 Chevy Biscayne 4dr sedan, AND owning a real '59 Biscayne 4dr from 1994-2005, those cars were NOT heavily built--they just looked that way. In short, they were large sheet-metal "boxes" with not much in behind them to stop an impact.

A long-time next-door neighbor when I was a teenager owned the largest tow-truck operation in my city--I got to see more than my share of wrecked cars, including '59-'60 full sized cars that were as badly crushed and crumpled as the '59 Chevy in that video. As for the engine, most generally that got punched way back into the interior, many times in a severe head-on collistion, the engine block would wind up where the front seat cushion was supposed to be. In addtion, little was known back then about how to "engineer" the crumpling of the front of the chassis, front-end sheet metal, even the body shell itself.

Art

[Modelmartin]

Modern cars are in every way superior to older cars except for the nostalgia. Older cars are quite superior in nostalgic qualities.

[Harry P.]

Modern cars are in every way superior to older cars except for the nostalgia. Older cars are quite superior in nostalgic qualities.

Exactly.

Old cars can't even come close to today's cars in terms of reliability, performance, and safety.

[Greg Myers]

Great memory Art. Wish I could remember things that far in the past as well as you seem to.

[Longbox55]

Should also be noted, all the so-called "rust" that most folks like to point out in that video, is actually dirt. Those late '50s cars were known for collecting dirt in the fenders, especially over the headlamps (that's one of reasons you see that area rusted out so often).

For those who believe that modern video was faked, here's one that was filmed back when these cars were new.

http://youtu.be/-MGKBD4BA6E WARNING, this video is rather graphic, with actual accident scenes and victims.

[Greg Myers]

so-called "rust" = (that's one of reasons you see that area rusted out so often)