Unibody rigidity

Are we still in 4 figures Nm/degree-wise or we're long in 5 digit territory?

I see the % improvement in the press from time to time but no actual figures for any car[s].

Reply to
I hate front wheel drive, most torque must go to the rear
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I had a 1997 car, and put lowered sports suspension on it. When parked on uneven ground, the front doors were hard to close, which means not enough rigidity. The next model was beefed up (probably to get more stars in crash tests) and was quite stiff, had no such problems. and was

Reply to
bruce56

I had a 1980 Citation (MT Car of the Year!!!) and it was the most flexible car I have ever owned. Felt like a wet noodle.

Reply to
Ashton Crusher

NYS bought some of the first generation Chrysler mini-vans and discovered that the chassis was not even close to sturdy. They would open the sliding door and then discover that after they got the people in that the door wouldn't close and you could see ripples in the roof panels from the stress. Chrysler used the same approach to repair them as they did the K-Car convertibles. Extra rocker panel braces to stiffen the unibody.

Reply to
Steve W.

My 1981 Buick Century: Noticed lots of squeeks and rattles. I relocated t he strikers inward on all four doors in that thing, and it actually began s peaking German! Seriously - the body felt tighter, the suspension respond ed more readily to both the road and my inputs. It felt more like an Autob ahn burner than a cushy Detroit rolling library.

My 1996 Ford Contour: Much taughter little sedan than the Buick for sure. But I read in the chassis manual I bought for it that both the front and r ear glass "must be properly mounted and sealed to insure body rigidity."

Are unibodies(like that Mondeo/Contour) that dependent even on the fixed gl ass for total rigidity??

Reply to
thekmanrocks

My 1981 Buick Century: Noticed lots of squeeks and rattles. I relocated t he strikers inward on all four doors in that thing, and it actually began s peaking German! Seriously - the body felt tighter, the suspension respond ed more readily to both the road and my inputs. It felt more like an Autob ahn burner than a Detroit rolling library.

My 1996 Ford Contour: Much taughter little sedan than the Buick for sure. But I read in the chassis manual I bought for it that both the front and r ear glass "must be properly mounted and sealed to insure body rigidity."

Are unibodies(like that Mondeo/Contour) that dependent even on the fixed gl ass for total rigidity??

Reply to
thekmanrocks

My 1981 Buick Century: Noticed lots of squeeks and rattles. I relocated t he strikers inward on all four doors in that thing, and it actually began s peaking German! Seriously - the body felt tighter, the suspension respond ed more readily to both the road and my inputs. It felt more like an Autob ahn burner than a cushy Detroit rolling library.

My 1996 Ford Contour: Much taughter little sedan than the Buick for sure. But I read in the chassis manual I bought for it that both the front and r ear glass "must be properly mounted and sealed to insure body rigidity."

Are unibodies(like that Mondeo/Contour) that dependent even on the fixed gl ass for total rigidity??

Reply to
thekmanrocks

Most newer vehicles use the glass as a structural part. The glass is also used in concert with the airbags for passenger restraint during accidents.

Reply to
Steve W.

Steve W. wrote: "Most newer vehicles use the glass as a structural part. The glass is also used in concert with the airbags for passenger restraint during "

Doesn't say much for the 'rigidity' of unibody does it? I guess it goes with the territory: Remove the subframe(body-on-frame vintage), and that strength has to some from someplace else. Thicker guage sheetmetal? Now that's an idea.

Utilizing the glass in concert with the airbag does, however, make sense.

Reply to
thekmanrocks

The glass is also used in concert with the airbags for passenger restraint during "

with the territory: Remove the subframe(body-on-frame vintage), and that strength has to some from someplace else. Thicker guage sheetmetal? Now that's an idea.

Reducing weight and increasing the stiffness of the parts that the drivetra in is bolted to is a good thing to do. If you can meet both goals at the sa me time, it's simply good engineering. It's not that radical a comcept - so me motorcycles have been using the engine as a stressed part of the frame f or a while.

Reply to
dsi1

The 1934 Chrysler Airflow was very well designed as a unit body for that time.

Reply to
sctvguy1

That is interesting. I did not know that. Thanks.

Reply to
dsi1

Unibody has been in use far longer than a lot of people think.

You also have to consider how the rigidity of the design effects the ride quality and safety.

You could design a vehicle that was very rigid and had no flex. It would have the ride of a solid block of concrete and survivability would be low in a major impact.

For examples of unibody just look at Mustangs (and every variant of the fox body), Camaros, Every Chrysler car since 1961. Pretty much every other car built by all makers since the late 90's. Trucks and some specific vehicles still have BOF construction but it's a very low count these days.

These days with safety and fuel mileage they look at everything for ways to make the vehicle lighter. One of those is thinner stronger steel alloys and using more of the components of the body to carry the weight.

Reply to
Steve W.

Look on youtube for the video of the 1934 Airflow going off a cliff, then driving off under its own power!

Reply to
sctvguy1

I have seen this famous footage. I'd like to see them do that using a modern car. That would be cool!

Reply to
dsi1

Years ago our agency bought a bunch of K-cars. They flatbedded them out to usage sites. On the flatbed they attached straps to the frame to anchor them to the trailer. Doing so bent the frames......

Reply to
Ashton Crusher

I believe the largest Unibody car ever built was the 1960 Lincoln.

Reply to
Ashton Crusher

Car maybe. The GM vans were unibody up until 96. They built cargo trucks on that design.

Reply to
Steve W.

1994 G20 Chevy Van.. wheelbase 125 inches, overall length 204.1 1960 Lincoln wheelbase 131 inches, overall length 227
Reply to
Ashton Crusher

That would be a "normal" van. They also sold them as cab/chassis or cut-aways to companies who then installed regular cargo boxes and ambulance bodies as well as motorhome bodies on them, Many added frame rails to the rear but there were quite a few that simply changed the rear axle to a dually design and bolted the stuff onto the factory floor pan.

Something like these

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Reply to
Steve W.

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