hi everyone, i was wondering if anyone has ever tried to tie the front end together with somthing similar to a strut tower brace. i know i know, there are no "towers" in the front, thats obvious. but what about it you went from the top of the sping (or shock) mounts and went through the wheel wells to the other side. this would run across where the spare tire is and all. i just think that it would help alot with the flex in the front. has anyone out there done this?
A sway bar doesn't address flex. It counteracts body roll. That's why some people confuse a Strut Tower Brace and Sway Bar. The STB is to make the chassis more rigid, and the sway bar is to keep the car level in corners.
A sway bar doesn't address flex. It counteracts body roll. That's why some people confuse a Strut Tower Brace and Sway Bar. The STB is to make the chassis more rigid, and the sway bar is to keep the car level in corners.
exactly. i want the chasis to be more ridgid. this ill effect handling becasue the suspension has a more stable platform to work off of.
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10:31 PM
Formula88 Member
Posts: 53788 From: Raleigh NC Registered: Jan 2001
About the only thing I can suggest is to reinforce the crossmember.
but how much different is the 88 front in comparison to the earlier cars. i know there is alot of suspension differences. basically though, what i was thinking is runing a brace across the top of that cross member. also, if the cross member was renforced to the frame rails (like you said earlier i think) that would help. im alreayd temped to get the add in frame that is made for the convertables and targa tops. that i think would really help. then i could shave soem weight somewhere else. its amazign how a few peices of metal in the right places woudl help make the whole structure that much more solid
Joel 87 GT 5-speed
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11:13 PM
Aug 19th, 2004
Rickady88GT Member
Posts: 10649 From: Central CA Registered: Dec 2002
The front and rear end of the 88 is much more rigid than the pre88's. If you have an 84-87 you would get the best rigidity from aluminum cradle mounts in the rear and tie the cradle to the frame rails with some steel "ladder" beams. The front can use larger steel frame rails that tie the X member to the front frame rail X beam. I dont see how a strut tower type member will help in this case. Much of the flex is between the doors not the wheels. After the aluminum bushings are in the rear and beefed up beams in front the best thing to do is put a structure under the car that like has been said will support a convertable. At one time I thaught about getting a spot welder and just rewelding the entire car with extra welds. I dont think that the car has enough welds. This lack of welds causes the flex. But that may be how GM wanted the car, it bends but dont brake. I wanted a stiffer car but without adding any extra weight. I have seen a car that had about 20 broken spot welds in the rear. It was rear ended but the welds gave way before the car crushed, and it was not hit that hard. I dont think that is how the car is suposed to resist stress. I know of several arias that I would beef up to help the structure without adding a roll cage or alot of extra weight. Another place to look is the "A" pillar's. You can fill them with some type of expanding foam. I know it dont sound like much but it will help a little. Or add sheet metal to them and the center roof section. Like a built in roll cage. Add gussets to all of the stressed sections of the frame where there are 90deg corners like in the engine bay. look at the fame rails where it conects to the firewall, it is a very weak joint. The list goes on and on. But like I said GM made the car so it would flex. If you take that flex out and dont do it right the car will brake at the weak point. If you do do it right it should ride great.
no, not offroading. if you take your car hard through a corner you can feel it actually flex, or like when you drive down a curb from a drivway, and go off it at an angle (have to, its lowered) you can feel the chassis flex. by making it more ridgid, the cars suspension will be able to work better, since it has a more stable platform to work with. with a flexy chassis, the suspension works against itself. on a ridgid chassis, the spring will compress against the car, liek it should. but on a flexible chassis, the spring pushes, and does compress against the chassis, butt he chassis will actually bends also, changing suspension geometry, and in turn, work against the shocks, struts, springs, swaybars, ect.
there is alot of flex in the middle of the car, thanks to the unibody. so by adding a sturcture undernieth it will help with the entire car.
how? unibody = the body is the frame, correct? fiero is an internal frame -- granted the passenger cell could use some reinforcement but I believe an x-frame is a very poor way to go about it
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Main Entry: unibody Definition: of a vehicle, a one-piece frame and body structure
unibody? fiero isn't a unibody - and no i've never felt any flexing - only suspension movement
maybe you dont understand what im talking abotu with the flexing. i feel it, and just about everyone i know that has a fiero feels it as well. and yes, the fiero is a unibody. the front suspension has a seperate frame from the rear suspension. there is no frame that runs the entire lenth of the automobile. a full frame car is say a truck, with a frame underit, and the body is placed on top. or a 70 GTO has a full frame. when you look under the car, you can see frame rails run the entire lenth under the vehicle. when you look under the fiero, there are sections that have no such frame under it. thisis why you can only lift the car at certain places. the 2 frame sections are held together by the body. in the fieros case, it has an internal body that the plastic panels are attatched to. this is the spaceframe.this is different than a full frame. i love the car, im just looking for a way to stiffen the entire car as i want it stiffer.
oh, and i love the idea of the targa top, but make sure you renforce the frame, or you will run into a whole nother set of problems. best of luck with that! i would love a targa, but not with this fiero
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06:36 PM
Formula88 Member
Posts: 53788 From: Raleigh NC Registered: Jan 2001
Actually, not. It's a space frame. The reason it's not a unibody is there are not structural body members on the car. It's a bit of a nit pick, but to be accurate, has more in common with a full frame car than a unibody.
special - i like that - i can settle for calling it special - still not a unibody ;-b
my reinforcement plans are 2" box welded along the frame rails in the rockers terminated into some 1/8" flat plate that will be welded to the front and rear firewall areas (possibly a verticle box section to the rear frame rail also) if necessary i'll reinforce the floor pan over to the center tunnel and reinforce the tunnels attachment to the front and rear firewalls.. turn it into a bit of a torque tube.. i think all of that may be overkill tho - but i was raised to build castles out of rock not cards
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09:25 PM
DotTC Member
Posts: 2345 From: Hamlet, North Carolina Registered: Nov 2003
Actually, not. It's a space frame. The reason it's not a unibody is there are not structural body members on the car. It's a bit of a nit pick, but to be accurate, has more in common with a full frame car than a unibody.
You make good sense.
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09:49 PM
Aug 20th, 2004
Rickady88GT Member
Posts: 10649 From: Central CA Registered: Dec 2002
The Fiero is called a "Space Frame" by GM because it has a plastic unstructural body mounted to a unibody frame. It is just a sells gimic. The Fiero is a unibody car. The only diferance between the unibody and a "Space Frame" is that ALL of the unibody of a "Space Frame" car is coverd by easy to change body panels. The Fiero was suposed to get an all new body change every few years at a nerzero cost to GM. For the cost of replacing worn out molds GM can just make new molds with a diferent body style and keep people interested in the little unibody "P" car. That is the whole purpose for the "Space Frame" With the extposed members of the unibody you cant realy make an entire new body change, you have the exposed members that you have to encorporate into all the new body changes. Just look at the 90 prototype. You cant see any body panel (maybe the roof) that is used on any other Fiero. But the unidody frame "Space Frame" under the 90 prototype is an 88, witch will take ANY other year Fiero body panels.
Space Frame= a unibody frame that is covered by a non structural easy to change body. This also make crash damage easy to fix. You can repare the damege then just cover up the ugly repare with a new body panel, this means less labor costs to smooth out the damage.
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Rickady88GT QuadCam 3.5 V6
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12:53 PM
PFF
System Bot
DotTC Member
Posts: 2345 From: Hamlet, North Carolina Registered: Nov 2003
The Fiero is called a "Space Frame" by GM because it has a plastic unstructural body mounted to a unibody frame. It is just a sells gimic. The Fiero is a unibody car. The only diferance between the unibody and a "Space Frame" is that ALL of the unibody of a "Space Frame" car is coverd by easy to change body panels. The Fiero was suposed to get an all new body change every few years at a nerzero cost to GM. For the cost of replacing worn out molds GM can just make new molds with a diferent body style and keep people interested in the little unibody "P" car. That is the whole purpose for the "Space Frame" With the extposed members of the unibody you cant realy make an entire new body change, you have the exposed members that you have to encorporate into all the new body changes. Just look at the 90 prototype. You cant see any body panel (maybe the roof) that is used on any other Fiero. But the unidody frame "Space Frame" under the 90 prototype is an 88, witch will take ANY other year Fiero body panels.
Space Frame= a unibody frame that is covered by a non structural easy to change body. This also make crash damage easy to fix. You can repare the damege then just cover up the ugly repare with a new body panel, this means less labor costs to smooth out the damage.
seems to be that the definition of unibody is the source of confusion -- everything i've seen says a unibody is a one peice combined frame/body.... by the simple fact that the fieros body panels are removable and non structural that excludes it form being a unibody.
edit: however after more examination
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A unibody frame is not a separate entity from the body of the vehicle and it is each and every panel of the car. Unibody frames have two frame rails and usually a front engine crossmember or a engine cradle to support the weight of the vehicle. They have impact crush and crumple zones that collapse on impact. They send the impact of the collision along the vehicle in certain ways, this causes significantly more damage to the exterior of the vehicle but is far safer for the occupants.
the unibody FRAME - just means it is a one peice structure - cosmetics would not be relevant in what type of frame it was..
its all in the definition -- so i will now agree it is a unibody FRAME ..
[This message has been edited by Kohburn (edited 08-20-2004).]
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01:06 PM
Rickady88GT Member
Posts: 10649 From: Central CA Registered: Dec 2002
Yes an No It is just a very small detale. There is a Huge diferance between a conventional body on frame and unibody. In a conventional body on frame like a truck or older cars the body has little structural value, most of the structure is in the frame. In a unibody the body is the frame and even the roof is like a roll bar. But the Space Frame is a unibody frame that is TOTALY covered with a plastic type of body. There is the same huge diferance between a Space Frame and a conventional body on frame car. But a very small diferance between a unibdy and Space Frame. So Yes you can say the Fiero is a Space Frame but you cant say it is not a unibody, because they are so close to being the same thing. I think the confusion is in the term Body. By body I mean the The entire structure that the driver is in, not just the outside part of the car that is painted.
[This message has been edited by Rickady88GT (edited 08-20-2004).]
