C4 body flex while jacking. Do you get it?
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Team Owner
Joined: Mar 2000
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From: Boston, MA
C4 body flex while jacking. Do you get it?
I'm just wondering if this is normal. When I jack up one corner of my car at the jacking point, typically the entire side of the car lifts up. Do most of the other early C4s do this also, or are those Z51 extra frame braces really that beneficial?
Thread Starter
Team Owner
Joined: Mar 2000
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From: Boston, MA
oh yeah, its "normal" for the C4 with its chassy design flaws.
Safety Car
Joined: Jul 1999
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From: Marianna FL
Re: (Black87c4)
:confused: Mine will do the same. I would think that the entire side comming up would be a good thing no, means the car is stiff right :confused:
Le Mans Master
Joined: Mar 2001
Posts: 9,464
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From: Modesto CA
Re: (Mr Dave)
I see that Camber Brace as being the same thing to the C4 has a Strut Tower Brace is to an import. :rolleyes:
Scorp- Yeah, I think with the Z51/2 frame stuff it does it more. Because on my 85 FE1 car I didn't notice it much, it just kinda did a 3 wheel motion. (same with my friends 88 IROC) and on the 87 Z52, man! That thing gets off the ground on whatever side! (kinda worries me, cuz I think it's twisting the frame)
Scorp- Yeah, I think with the Z51/2 frame stuff it does it more. Because on my 85 FE1 car I didn't notice it much, it just kinda did a 3 wheel motion. (same with my friends 88 IROC) and on the 87 Z52, man! That thing gets off the ground on whatever side! (kinda worries me, cuz I think it's twisting the frame)
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Re: C4 body flex while jacking. Do you get it? (Vince Ivanc)
The whole side comes up on mine, too (Z51). I've notice that, with the top off my car, when I pull into my brother's driveway (it's real steep) when that first wheel starts up the incline it feels like the car's gonna fold in half. Just my perception.
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From: Lacey WA RVN 68-69
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Re: C4 body flex while jacking. Do you get it? (scorp508)
If I use the jacking points where they are marked, I do get some flex on my 92 roadster. I usually release the hood, and the doors before jacking. I also bring the door windows down a bit.
What I have found is that I can jack the car up at the center point between the marks when I want the entire car off the ground and there is not anywhere near the body flex. You just have to be careful to keep the jack pad away from the brake and fuel lines as they are real close to the body seams. I don't get any interference at the lower body molding with the jack pad so no damage. Doing it this way allow me to position 2 jackstands on a side for the height I want and just lower the car onto them.
What I have found is that I can jack the car up at the center point between the marks when I want the entire car off the ground and there is not anywhere near the body flex. You just have to be careful to keep the jack pad away from the brake and fuel lines as they are real close to the body seams. I don't get any interference at the lower body molding with the jack pad so no damage. Doing it this way allow me to position 2 jackstands on a side for the height I want and just lower the car onto them.
Thread Starter
Team Owner
Joined: Mar 2000
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From: Boston, MA
Doing it this way allow me to position 2 jackstands on a side for the height I want and just lower the car onto them.
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Joined: Apr 2000
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From: CT
Re: C4 body flex while jacking. Do you get it? (corvette0096)
Mine does it too.
The post a while back regarding opening doors-hoods etc was different. I'd never heard of such a thing before. I never do any of those things, slide the jack under, up up and away :D
The post a while back regarding opening doors-hoods etc was different. I'd never heard of such a thing before. I never do any of those things, slide the jack under, up up and away :D
Racer
Joined: May 2001
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From: TX
Re: C4 body flex while jacking. Do you get it? (JD 90 383)
I agree with JD. I jack where I am supposed to and can get the whole side of the car high enough off the ground to place jack stands front and rear. This is a sign that the chassis is stiff, not flexible. I had to change tires on an F-body this weekend, it absolutely sucked having to jack the car up 4 times to change 4 wheels. The car even had a cage in it. It still was more flexible than my FE1 C4.
Thread Starter
Team Owner
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From: Boston, MA
This is a sign that the chassis is stiff, not flexible.
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From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: C4 body flex while jacking. Do you get it? (Vince Ivanc)
Vince is right. Also, springs also make a difference. Just think about it for a minute people!
Racer
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From: Micco FL
Re: C4 body flex while jacking. Do you get it? (Mez)
The fact of the matter is this car was designed to have a bar running from the back to the front, as in earlier models, and and not a targa. At the last minute GM big wigs said make this a targa, but the frame was already designed for the older style bar.
[Modified by PTz-92-LT1, 10:46 AM 7/17/2002]
[Modified by PTz-92-LT1, 10:46 AM 7/17/2002]