1959-1960 Buick question

[X-Frame]

Outside of the fact that the 1959-1960 "Delta" winged Buicks were different than other years, why did Buick decide to change the chassis from an X braced design that ran between 1932-1958, change it to a K frame in 1959-1960, then back to an X between 1961-1964? Was there a reasoning behind the radical change just those 2 years?

[Pete Phillips]

I don't know all of the reasoning, but I do know that GM was trying to lower the height of its cars. GM was chasing the styling leadership of Chrysler Corporation in 1957, when the '59 and '60 Buicks were being designed. Chrylser had just come up with fabulously long and low styling in 1957, and the old X frame on GM cars had a huge amount of wasted space. If you crawl under one, you are amazed at all of the unused space between the frame, because the floors are relatively flat and do not extend below the top of the X frame prior to 1959. In 1959 and especially in 1961, the GM cars have deep footwells in their floors, essentially lowering the interior floor to the bottom of the K frame or X frame from 1961 onward.

Pete Phillips

[WQ59B]

^ To clarify, the GM '59-60s still have the flat, 'above-frame' floor in the front seat... but the seat bottoms were pretty dang low there, too.

Only the rear had dropped floor pans in '59-60; X-frame or K-frame.

'X-Frame' : good question.

[NTX5467]

One side issue with the front floor level not being recessed, when the rear footwells were, would be to make the transmission "hump" seem much less tall. This would make the front seat seem much more spacious in nature. In the rear seat, the issue was more related to the distance between the front of the rear seat cushion and the back of the front seat.

Seems like Buick advertised that they'd moved the engine a few inches forward in the chassis, starting in a particular model year, which allowed for a less tall transmission floor hump . . . as a marketing advantage?

With the seats being closer to the floor, it compensated for the somewhat lower rooflnes. Might have only been 1/2 inch, but that could mean the difference between wearing a hat while driving or having to take it off.

Just some thoughts,

NTX5467

[X-Frame]

Thanks guys, maybe we can come up with something a little more on this.

One thing I do find annoying when building or collecting model cars of 1:1 vehicles is that being a stickler for accuracy, I judge quality by the chassis they represent.

While looking at a 1:18 scale diecast model by Sun Star of a 1958 Buick Riviera coupe, I noticed that the frame they used is totally incorrect and it is of a 1959-1960 Buick K frame! The 1958 still used a perimeter frame with center X bracing. Why don't these people do a little "real car" research first before making these model cars?

I should have known that even if their overall looks are good that they overlook details like chassis. Years ago I purchased one of their first offerings, a 1955 Ford convertible in 1:25 scale. It had a closed body frame on it minus the convertible X brace. I see this mistake often especially on resin kits.

Edited January 17, 2012 by X-Frame (see edit history)

[X-Frame]

So far the only thing I can find out is similar to what has been said above. That Buick broke away from tradition to be able to lower the floors but the K frame still limited front leg room. In 1961 they went over to the tubular center X frame like the other GM cars had which allowed the front floor to also be dropped further.

Can anyone else elaborate or make corrections?

Does anyone have a body-off frame picture of a 1959-1960 Buick (non brochure)?

[X-Frame]

Wanted to also add a little-known fact is the slight frame difference between the two years that allowed the front floor to be lowered for 1960, even though both years share the same wheelbase. It is just slight reinforcement bracing changes in the K area.

[NTX5467]

Considering the price point many model makers generally try to hit, not changing things "under the skin" as they change things highly visible is one way for them to help contain their tooling costs, I suspect, just as the full-size vehicle manufacturers do. It could also be that they presumed the frames to be the same?

As to what Pete mentioned, I saw an interview with Chuck Hols (sp?) on one of the cable car shows in the 1990s (either "My Classic Car" or "Motor Trend Television"). At that time, he was a young stylist in one of the GM styling departments. When they heard of the new 1957 Chrysler products being parked in an open, but fenced, parking lot, he said a group of GM stylists went down to see what they were. As he noted, "We hung on the fence drooling and wondering 'How'd they do that?'" Then, they rushed back to their drawing boards and started revising their 1959 designs, as what they had was not (they felt) going to be competitive with what Chrysler had done.

It could well have been that they needed a different chassis frame design to do what they felt they needed to do. You can bet that they probably had to get "upper management" approval for using the frame designs they did, rather than what other GM divisions were using. IF the different frame cost more money to use, there were also probably some other areas of the cars where less-costly items were used to compensate for the (suspected) more expensive frames. In other words, it wasn't something they could do on a whim, but had to be integrated into the vehicles' total production cost, somehow.

Just some thoughts,

NTX5467

[WQ59B]

1959 Buick frame :

• • •

>>"One side issue with the front floor level not being recessed, when the rear footwells were, would be to make the transmission "hump" seem much less tall. This would make the front seat seem much more spacious in nature."<<

Could be, but not a really smart way to do it. The trans tunnel wasn't lower; the floor was higher.

[WQ59B]

1959 Impala:

Other '59 Chevy frame pics: http://www.xframechevy.com/1959/1959-impala-convertible-x-frame/

1960 Chevy:

Gains side rails here...

Edited January 23, 2012 by WQ59B (see edit history)

[WQ59B]

1959 Cadillac :

[X-Frame]

1959 Impala:

1960 Chevy:

Gains side rails here...

Nope, didn't gain side rails - just looks that way. This is just colorized to show the "body" structure. This is the rocker panel area of the body which all these cars had.

[X-Frame]

1959 Buick frame :

• • •

>>"One side issue with the front floor level not being recessed, when the rear footwells were, would be to make the transmission "hump" seem much less tall. This would make the front seat seem much more spacious in nature."<<

Could be, but not a really smart way to do it. The trans tunnel wasn't lower; the floor was higher.

That is true... you can see that the front floorpan was flat... even with the rocker of the body area while the rear area was wide open to drop to the ground.

[X-Frame]

The 1959-1960 Buick's isn't the only GM oddity.

The 1940 Chevrolets were a one year only design and their convertible frame was an overkill monster and also only used one year, one car only.

And the 1935 Chevrolet Standard had an X braced chassis while the other models had a YK frame. A one year only offering as Chevrolet didn't use an X design again until the 1941 Convertibles.

The question would be why they did these cars different as well? Tooling for the 1940 Chevrolet as a one year only car seems a bit extreme so not sure about "buget" factors here?

Possibly there is some history behind the Buick that ties in to these past attempts?

[WQ59B]

You are correct WRT the '60 Chevy frame- I was indeed tricked by the show chassis. RPO C-60 frame :

[WQ59B]

'59 Olds frame : Directory Index: Oldsmobile/1959 Oldsmobile/album

[X-Frame]

'59 Olds frame : Directory Index: Oldsmobile/1959 Oldsmobile/album

All bodies had rocker backing in the body or the body cabin shell in that area would just crumple and flex and the doors bind.

Yes, the Oldsmobile did add a perimeter frame on their tubular center X configuration for the 1959 and 1960 models. They boasted being so wide that it doesn't need outriggers to bolt them to the body but bolts directly to it. You need something to "bolt" to. In 1957 and 1958 they had a older design X brace in the perimeter frame and in 1961 Oldsmobile went to just a boxed perimeter frame sans the X. It was the only GM make that used the outside rails in conjunction with the newer post 1957 design X.

You would be able to see that in a picture like the Chevrolet show one but even the Oldsmobiles, if you were to take the body off the frame and flip it to see the body bracing would still show those outside rockers

[X-Frame]

That said... I ran across a couple more pieces of information. besides GM trying to work fast forward after seeing the 1957 Chrysler lines, one publication said they needed a new chassis for the new body that allowed "rear" leg room. It didn't mention any front room advantage but the 1960 was silghtly redesigned to help with that until, I guess, those frames were used up and switched to the tubular X for 1961?

Press releases given to various magazines in 1958 called the new K frame a Equipoise Chassis.

Eric

[WQ59B]

That Chevy frame did throw me. I saw the square boxed rails, with what looks like a pair of drain holes, but I should've noticed the floorpan braces were attached to them, whereas on the '59 Buick, those same stamped braces cross above the frame & attach to the rocker backs. I own a '59 Buick, and spent many hours underneath it, cleaning/ scraping/ painting- so those braces are very familiar to me.

RE the Olds bolting directly to the frame is interesting, but of no real difference- they just as well could have used inboard outriggers with the same results.

[X-Frame]

That Chevy frame did throw me. I saw the square boxed rails, with what looks like a pair of drain holes, but I should've noticed the floorpan braces were attached to them, whereas on the '59 Buick, those same stamped braces cross above the frame & attach to the rocker backs. I own a '59 Buick, and spent many hours underneath it, cleaning/ scraping/ painting- so those braces are very familiar to me.

RE the Olds bolting directly to the frame is interesting, but of no real difference- they just as well could have used inboard outriggers with the same results.

For 1960...see how that heavy cross beam that the driveshaft goes through arches a bit on your Buick? I believe that was notched down some (not as wide). A slight support bracing difference within the K as well was removed and a larger outrigger added to compensate. This I am sure helped with the front floor lowering for the '60.

Edited January 25, 2012 by X-Frame (see edit history)

[X-Frame]

I just wanted to get back to show the differences between the 1959 and 1960 Buicks K section. In looking over my charts I also noticed a couple more differences. One being that the 1959 frame splays out more at the front by almost 3" on the 1959 and is straighter on the 1960. The end cross rails that sit behind the bumpers are also different between the two years. As for the K differences, below are clips from the charts so you can see them. 1959 on the left, 1960 on the right.

[X-Frame]

Bumping back to the top hoping others can contribute or answer the elusive question

[Mark59]

Here is a '60 Buick convertible frame I bought to replace the rusted one under my '59 LeSabre flattop.  There are slight differences between the 2 years, mostly in the front/rear X-members & front frame rails.  The '60 also had a slightly lowered front floor, but I'm not sure that applied to the ragtops as it appears identical in the K area as my '59 hardtop one.  Certainly a lot more protection in a side impact than an X-frame.  Design could be inherent to the forces caused by the torque tube (Buick specific) as opposed to the open drivelines of the X-frames.  Olds used a hybrid of the two frames with rear leaf springs for '59-'60...

[Mark59]

BTW, I plan to cut the front sections of my '59 rails right before the spring support and weld them to the '60 frame as they are the same up to that point and are different as you go forward.  See pic for details of cut/joint.  rears are easy as you just need to drill the rivets, cut the welds (top & bottom) and swap it out; the rails are the same for both.  As for the wider body mounts, it just bolts to a different area on the floor brace (no need to modify anything on the '59 body, just install the bolt/donuts in a different hole on the brace)