matthew

I've heard that term throw around hear a lot. I assume it means "one-body" since uni means one. But what does it really mean and what would be the other type of body to get?

------------------
yellow 86 Camaro LG4
Pioneer head unit
Kenwood speakers
Infinity Beta Digital 300 amp
2 Infinity Perfect 12s

ViciousZ

iTrader: (1)

Unibody is the type of chassis that all camaros come with. It means that they use the body of the car as part of the car's overall structure instead of using a separate frame. Basically what this means is that the structure of the car is weak and succeptable to flexing and twisting, especially when turning or going up or down a ramp, like a driveway. A good analogy that I've heard is to think of your car as an icecube tray: whey you turn, the body of the car twists like that. You can significantly strengthen the car's structure by installing a set of subframe connectors, which are basically metal 2x4s which go along the underside of the car. A strut tower brace will help, too.

JPrevost

He's exactly right. Icecube tray is exactly what our cars are. After I installed my SFC and S.T. brace I noticed right away how tight the car felt. No flexing around corners and no more cracks in the roof/window corners. Too bad our cars didn't come with any good body engineering. That all went to the corvette.

------------------
, Jon (91 RS too many mods to list)

stingerssx

Also, uni-body is short for unit body frame. Also known as:

F-body, for fox chassis


and the best damn ride in town!!

------------------
'82 Firebird, dead stock, 9 bolt disc rear, over 200,000 miles and still going strong, more to come...

84FTA

First and second gens have full frames along with most other cars from pre-80's. I like the ice cube tray comparasion too. The reason for eliminating the full frame was to save weight and probably helped with emissions/mileage.

There is a truck commercial that shows a full frame....basically that's what we don't have. They show the frame from front to rear. We just have the front area and the rear area leaving the center to kind of "fend for itself" in terms of rigidity.

------------------
1984 WS6 Trans Am Hartop
Former L69 Car under restoration
1984 WS6 Trans Am T-top car
4-bolt main 350, headers, Holley 650, T-5 and 3.23's.
Daily driver and restoration
13.98 @ 101

Guest

2nd gens are unibodies too. Im not sure about the first gen. Rustangs have been unibodies since day 1.

Vader

My PrimoBird (1967)n was also a unitized body/frame design. It had a floating (rubber isolated) subframe front end and integral (welded) subframe rear. SFCs have been around for these cars sine May of 1967, when NHRA ruled that they needed a rigidized frame for drag racing in certain brackets. The rest, as they say, is history.

------------------
Later,
Vader
------------------
"No matter how hard you try you can't stop us now"
Adobe Acrobat Reader 4.0

JPrevost

Okay I think we got that unibody thing down but here is my question. Everybody knows how 1st gens have body bushings that usually need to be replaced. Now how can a car have body bushings when it's a unibody. Wouldn't that mean it's a frame front to end? If it wasn't connected then the "bushings" would have to really be washers to hold the frame ends from dropping? I know there is a simple answer for this and from what I've seen and what I've done with my friends 69 I'd say it's unibody but then I've never seen the body bushings. Please somebody clear this up for me before I call up my friend. :-)

------------------
, Jon (91 RS too many mods to list)

Apeiron

Someone correct me if I'm wrong, but I don't think the firstgens were unibody, they were on the same frame as the later Chevy II/Novas.

------------------
1984 Camaro Z28 Astral Silver w/ 2 1/2" cowl induction hood
Engine: Decked 383 cid 4 bolt w/ oil cooler, 9.6:1 compression, ARP fasteners, 600 cfm Performer carburetor, Torker II intake, Performer RPM Heads, XE268H cam, Magnum roller tip rockers, MSD6AL ignition, Blaster2 coil, recurved HEI distributor
Exhaust: Terminator headers, Custom 3" TIG welded stainless exhaust, Twister muffler
Transmission: 4L60 w/ Corvette servo, .500 boost valve, TransGo 7-CS clutch springs, 700 PKH pump rings, 700-2 reprogramming kit, Borg-Warner High-Energy frictions & bands, 2400 RPM lockup torque converter
Drivetrain: 2.73:1 limited-slip Dana 44 w/ disc brakes
Tires: Front P225/50VR15 Rear P265/50VR15 Eagles

Ed Maher

All F-bodies have been uni-body from day one. The reason for bushings in the first / second gens is to isolate the front subframe from the body. That's right kiddies, the front subframe from a first/scond gen can be unbolted and rolled out from under the car (ever see the pictures of ZZ3astros conversion...the front subframe from his astro is supposedly very similar to the second gen subframe.) Also, i have seen a second gen with the front subframe out to be replaced after wreck mangled it.
And apeiron, the 68-74? novas were built on the first gen f-platform, and are unibody.
...ed

[This message has been edited by Ed Maher (edited December 22, 2000).]

merf23

Actually, i would consider the front cross member in a 3rd gen to be a subframe. Also, full frames flex about as much as a unibody, if not more. They are like a ladder, rather than an ice cube tray. Their beam strength is very good, but torsionally they are poor. They need the rubber mounts because there is a lot of relative motion between the body and frame. Notice that all trucks have full frames and the cab and bed have a large gap between them to allow for flex. A properly designed unibody will be more rigid and weigh less than a full frame chassis. Indy cars are a unibody design for this very reason. I a passenger car the necessity for door openings significantly decreases the torsional strength of the design.

RB83L69

All F-cars have been unibodies from the start.

If you get up under a more real car, like a Caprice or a Monte Carlo, you'll see that they have a frame that goes from bumper to bumper. The body is entirely isolated from the frame. It sits on bushings at a handful of places. The suspension and drive train are attached to the frame, and the body is completely separate. This limits transmission of noise and road shocks to the body, and reduces the requirements for structural strength in body components.

Our cars, on the other hand, have a "subframe" that attaches the front suspension and the engine to the body; but the passenger cabin has no frame, and the rear suspension attaches directly to the body. There's some reinforcement of the body shell around the attachment points for the suspension, but it's welded directly to the body. The floor pan is the main structural component of the body.

This is one of the biggest reasons for subframe connectors: the engine and rear end are connected to each other only by the sheet metal of the floor pan. So all the various torques that the drive train exerts on the body are resisted only by sheet metal. In a full-frame car the frame carries all those stresses. A full frame is also more rsistant to twisting, which is the other reason for SFCs.

------------------
"So many Mustangs, so little time..."

82z

stingerssx, I'm pretty sure f-body doesn't have anything to do with fox chassis. 82-93(?) mustangs were known as the fox body.

------------------
82 z28 350cid, vortec heads, comp 262h cam, Holley 600cfm carb, 2in twice pipes, MSD ignition, turbo 350 trans, 3.73 posi, manly b&m megashifter

stingerssx

Actually, the G-body,('78-'87 Elcamino, chevelle, monte carlo, regal...) are full framed cars, and are the best platforms for road racing applications. They don't require any extra reinforcements, such as strut tower brace, or K member brace, or sfc's, or wonderbars. The frame is already stiff enough.

Also, yeah the mustang, (ugh!!) is also a fox body, and also a uni-body. It too has sub frames. Dodge also has a fox body.

------------------
'82 Firebird, dead stock, 9 bolt disc rear, over 200,000 miles and still going strong, more to come...

Red Devil

Body by Fisher... F-Body.

------------------
"I don't want to be right - I just want to know <i>if</i> I'm right"
-Einstein

MikeS

Right, our cars are "Body by Fisher". Says so on the door sill. But is that necessarily where the F comes from in F-body. I thought that was just a corporate designation. But if not, what does the Y in Y-body (vettes) and the G for the monte carlos, etc. stand for?

JPrevost

I was just going to ask that about the Y-body etc. Thanks for clearing up that 1st gen unibody w/body bushings thing. It was really throughing me for a loop.

------------------
, Jon (91 RS too many mods to list)

pat85yellowroc

i know for a fact that F body doesnt come from body by fisher, because my dad's 69 chevelle says the same thing. first gens did not have a full frame either. i read about how to restore subframes in 1st gens in "camaro performers" that was out this month.

------------------
beau-t-ful yellow 85 iroc

Red Devil

Hmm... that is a good point, I was always told it started like that and was incorporated by GM when they started using body designations. Now I'm curious, I think I'll look into this...



------------------
"I don't want to be right - I just want to know if I'm right"
-Einstein

Red Devil

Y'know, my greatest weakness comes in the form of curiosity...

As far as I can find, the 'F-car' designation comes from an internal GM brief from 1964. I found a bit of history behind this, and I can't yet pin whether the 'F-car' moniker was the next in line for body assignments or if it was made on a whim by a GM director. The history starts a bit before, and while it may not have much relevance, it is interesting...

In the early 60's Pontiac had a team of engineers and designers by the names of, Estes, DeLorean and Knudsen. By most accounts, they were young, brash, inventive and had the unequaled initiative of youth. They had already tried reworking the Corvette into the Pontiac line, but GM refused.
They wanted to build a sports car from the ground up. Really bad it seems. Estes and DeLorean in particular.
Pontiac , in 1963 they began designing the XP 833 designated sports car. By 1964 they had a prototype. About this time the (infamous) brief was sent out by GM management. It informed it's designers and engineers that GM had to build the 'F-car' to counterbalance the Mustang's market share.
From what I can tell, neither Estes, nor DeLorean wanted to get involved with the 'F-car' because they were convinced of the merits of their prototype. It seems that GM had other plans...
In the summer of 1965 Estes was promoted to general manager of the Chevy division, and DeLorean was bumped up to either VP, or GM of Pontiac.
DeLorean was still pushing hard for the XP 833 . It didn't work. Meanwhile, Estes embraced the 'F-car' in Chevy and began to resent Pontiac involvement in what he considered Chevy's backyard. DeLorean then tried a four seat version of the XP 833. No dice.
He then tried to rework the Corvette again and GM refused - again, however, he was then handed the 'F-car'.
Now this is where I have been given some conflicting accounts. Some say that from the first moment of hearing Estes not wanting Pontiac to work on the 'F-Car' DeLorean went out of his way to pester GM brass with these new prototypes, and others insist that Pontiac really did want a two seater. Beats me which.
In 1966 DeLorean did try to display a concept car (I think it was the XP798 or XP 833 not sure) at the New York auto show, and it was pulled before the show by a GM President. DeLorean then rolled it back out during the show and the same President saw it and flipped out. He had it yanked and destroyed it.
I have not been able to get a clear picture of the timeline of all these overlapping things, but I would guess that after the Auto show, DeLorean got the ok to play with the 'F-car'. I have yet to find out if the designation is still officially 'F-car' or if it is really now 'F-Body'. Semantics I guess.




------------------
"I don't want to be right - I just want to know if I'm right"
-Einstein

TexasFormula

Okay there's 2 types of vehicles uni-body, and body-over frame. Unibody is what it is its one solid body meaning meaning there is no chassis and the suspension bolts directly to the body itself whereas the body-over frame is what it sounds like it's a body laid on top of a frame (chassis). Most all trucks are body-over frame vehicles and most cars are unibody with the exception of some older models that consisted of a chassis and body.

MoJoe

iTrader: (5)

@TexasFormula - you do realize you resurrected a 15 year old thread, right? I don't think too many of the posters are still around.

TexasFormula

I figured I'd put the correct answer for future reference to those who maybe searching for this information.

novaderrik

i'm glad this got resurrected... it's funny when people that don't know what they are talking about state things as facts. did google exist when this thread was new, because all this stuff is easily searched..

"F" is just the GM internal designation given to the chassis used for 67-02 Camaros and Firebirds.

"X" is Novas and what not

"A" is midsize cars like Chevelles from 64-80 and the all new Citation that came out in 81.

"G" started out as a slightly lengthened version of the A bodies from 68-77 that were badged as Monte Carlo and Grand Prix, but the "G" designation got put on all midsize rwd cars in 81 because the new fwd Citation was given the "A" designation..

"B" is full sized cars like Caprices and Roadmasters from 64-96, "H" was a slightly lengthened version sold as a Cadillac.. but in the 70's, the "H" body was the Vega and Monza and what not..

i don't think they use the letter designations any more- they are all words like "Zeta" and what not now, because apparently that makes the cars better somehow.

InfernalVortex

iTrader: (4)

Are those letters the same as the ones in the Vin numbers? i havent seen enough Corvette/Chevelle/etc vin numbers to see... But I know most Camaros are 1G1F, and the 4th digit is the first "vehicle descriptor" value.... the next several are. But Im imagining this is the same as "FC" or "FD" RX7, or "AW11" MR2's, or DA9 civics. These are VIN codes. And that are in the same spot that my FP23 in my vin number is. So I assume these designations are probably repeated in VIN numbers for all these cars.

But agian... it's a 15 year old thread. I dont even know why Im responding honestly.

Zeta is a platform, yes, so is "Fox". But these were used on a lot of different cars. The letters we are used to seeing are PROBABLY from official Vin number designations. For example, my 1G1 F Camaro, and the 1G1 Y Corvette vin numbers (post 1981, before that I have no idea, maybe they already had the internal desginations and chose those for the VINs?). Firebirds will also have an F for the 4th digit, but Pontiac is a different value for one of the first 3.

sofakingdom

iTrader: (1)

Nope, sure aren't... a totally separate designation. Just like, the engine character isn't related to the RPO code in any way.

My Camaro starts out 1G1AP...

InfernalVortex

iTrader: (4)

(╯°□°）╯︵ ┻━┻)

mk1431

unibody= no frame

Lurbie

iTrader: (3)

The platform has changed over the years. The 5th gen Camaro is built on the Zeta platform along with many Holden vehicles. The new 6th Gen Camaro is on the Alpha program along with the ATS and CTS. Body designators in the VIN and platform codes used by GM are not the same thing, any similiarity is strictly coincidental.

Vader

HEY! Some of us resemble that remark...

The illustrious Mr. Benjamin answered the question 15 years ago, and the answer still hasn't changed.

And for the record, Google was around then, but was not anything like what it is today (nor what it is likely to become).

TTOP350

iTrader: (8)

Yeah, some of us have been here for awhile...