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Old Jul 30, 2018 | 06:55 PM
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Default chassis help -

hey everyone

The other day when I was out - for some reason I seem to notice just how much the car seems to flex(?) going over our lovely roads. I wondered if there are ways to firm up an '85? I read somewhere 86 and up had a kit but not the 85. I did not know if there was anything reasonable that the avg to less than avg person could put on that would help. I thought about reaching out to a few shops but that could probably get a little expensive - plus I would need to find one I could trust.
Nothing urgent - but I feel like I would not be the only one that could benefit - I would think a lot of 84 and 85 people might take advantage.

anyone ever look into this or try anything?

thanks

Sean
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Old Jul 30, 2018 | 08:25 PM
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keep the roof on
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Old Jul 30, 2018 | 09:13 PM
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Well, if you don't mind driving across 224 a ways, I will show you what I did to my car and take you for a ride so you can feel how I firmed it up. If it doesn't rain, Aug 2nd would be a great evening to do so. You could come over to the all Corvette cruise-in over here. I know it is a little bit of a drive, but it is basically 224 all the way.
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Old Jul 31, 2018 | 12:33 AM
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This has been discussed in detail in other threads. If you tighten up the chassis in one place the flex will move elsewhere.

https://www.corvetteforum.com/forums...solutions.html

There's way too much flex in the chassis for an easy solution. It would require substantial modifications to make any real change in stiffening the chassis from what I have gathered.
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Old Aug 1, 2018 | 12:03 PM
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that's a lot of stuff - I will need to re-read and maybe get an engineering degree or 2 -

recook - I came across a post or 2 of yours with a camber brace and harness bar - you seem to like that and it does not seem too intrusive?
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Old Aug 1, 2018 | 12:04 PM
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I do not think I have had the roof off since getting a new one - at least a year +
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Old Aug 1, 2018 | 12:56 PM
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Originally Posted by sb66
that's a lot of stuff - I will need to re-read and maybe get an engineering degree or 2 -

recook - I came across a post or 2 of yours with a camber brace and harness bar - you seem to like that and it does not seem too intrusive?
the only issue with the harness brace is that you cannot open the little doors in the back, so you can't get the jack out. at this point my spare is 20 yrs old and not under the car. if I can find or build a spare tire delete bracket, it won't make a difference, plus I am thinking of hanging a transmission cooler with fan back there.
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Old Aug 1, 2018 | 02:05 PM
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http://www.vansteel.com/index.cfm?fu...owItem&ID=2985

is this the same type of camber brace?
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Old Aug 1, 2018 | 03:54 PM
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basically yes. I have a 96 so it is slightly different for a LT1/4 car
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Old Aug 1, 2018 | 04:24 PM
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further reading mentions these are very if not too close to accessories and belts? but I would not think it would move much if at all with where it is?
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Old Aug 1, 2018 | 04:39 PM
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Granted that mine is a lt1, the bar just fits down in







Last edited by drcook; Aug 1, 2018 at 04:41 PM.
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Old Aug 2, 2018 | 06:10 AM
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Hi Sean its Sean here

3 ways to really tighten up an 85
Harness Bar
X brace
Camber bar
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Old Aug 2, 2018 | 06:44 AM
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thanks Sean -

triple threat!

I did not think there was a cross brace for the 85 - just for 86 and up? or is that the one for the convertible?
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Old Aug 2, 2018 | 07:14 AM
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Originally Posted by sb66
thanks Sean -
triple threat!
I did not think there was a cross brace for the 85 - just for 86 and up? or is that the one for the convertible?
thats right, the cross brace was introduced with the convertible in 86, all chassis from 86 onwards has the bolt holes.
to retro fit the cross brace you need to fit nutserts into the chassis, so its a bit of stuffing around, but then any of the options involve a bit of stuffing around !
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Old Aug 2, 2018 | 04:45 PM
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which one should you start with? I cannot get them all at once -

Also I. read there is or may be clearance issues with the x brace? - any truth to that?
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Old Aug 2, 2018 | 07:17 PM
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Originally Posted by sb66
which one should you start with? I cannot get them all at once -

Also I. read there is or may be clearance issues with the x brace? - any truth to that?
yes there are clearance issues with the x brace - the convertible's came out the factory with a higher ride height to compensate.

I would look at the Exotic Muscle harness bar - they tighten the rear up the 2 rear points and up into the seatbelt bolts in the halo
http://emracingcorp.com/scripts/prod...?idproduct=496


Also consider the C beam plates - if you can find some - they work
http://www.zfdoc.com/c4beamplate.htms


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Old Aug 2, 2018 | 09:32 PM
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vette 2 vette kit is the way to go IMO.

WAY better than the convertible X-brace.
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Old Aug 2, 2018 | 10:27 PM
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Have not heard of a C4 breaking in half yet, flex is something all vehicles have to varying degrees.
No flex means it will find a weak spot and crack leading to breakup, ever looked at a plane how much the wings flex
Forget about it, like that song goes don't worry be happy
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Old Aug 3, 2018 | 06:21 AM
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Originally Posted by rjacobs
vette 2 vette kit is the way to go IMO.

WAY better than the convertible X-brace.
I did not think they made anything for the 85 - has anyone tried to modify and adapt to fit?

why would it be better? just curious
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Old Aug 3, 2018 | 06:29 AM
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Originally Posted by gerardvg
Have not heard of a C4 breaking in half yet, flex is something all vehicles have to varying degrees.
No flex means it will find a weak spot and crack leading to breakup, ever looked at a plane how much the wings flex
Forget about it, like that song goes don't worry be happy
true - and I will never get it to the point of no flex - and probably do not want to I just wanted to reduce some so I do not have that water bed feeling over bumps and going in and out of driveways - but you make a very valid point - I came across many other posts that were adamant that all of these things were unnecessary for street cars. I think one of the articles I read that inspired some of this was about a vette that had a crack in the frame from overflexing (?) I think it was a c3 - got me to thinking about the flex in mine
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