Here's some ideas in ascending order of likelihood:

1. You're not getting them tight enough.
2. The mounts are maladjusted, and even though the bolts are tight, the sockets aren't bottomed in the receivers, and the bolts loosen from vibration.
3. Or maybe it's just a 30-year old POS 84. It wasn't very good when it was new. Now its worse. Put it out of its misery and junk it.

Ignore the haters, make sure you get them good and tight, make sure they haven't been stripped, and see if anything else is flexing. And enjoy that great 84!

dave, why would you suggest my car might be a pos and i should junk it.  are you angry about someting or is it just because you had on at some point, and it became a pos. i realy don't understand why you would even suggest this. by all means please tell us.

I agree with #1 & #2....I do NOT agree with #3....

The bolts getting loose isn't a common issue, as far as I know....I do know they have to be pretty dang tight to begin with, since the targa top is designed to be an integral part of the chassis. If they are left loose, the chassis flex could certainly make them looser as you drive.
Make sure when you install the top, that the car is on level ground...that will help keep everything lined up.

One of the reasons I haven't had my targa off but a couple of times on the '85 since I've owned it.

First off read it again. I didn't say your car was a POS, I said "maybe it's just a 30 year-old POS 84." Which if read correctly should indicate that I don't hold much esteem for any 84, regardless of condition, or who owns it.  I'm an equal-opportunity 84-hater. I was ready to buy an 84 in Summer of 83. I was told to wait for the 85 because it would have a TPI engine that would be introduced in the 85. I bought the 85 I still own today in June of 85, and am SOOOOOO glad I listened to the GM guy that told me to wait a couple of years for the TPI. 84's are dinosaurs compared to 85's.

IMO, my 85 is also a POS. Compared to many 85's mine is damn nice. NCRS Crossed-Flags, NCRS McClellan 98-point- something, , blah, blah, blah. But it's still an 85 C4. Which compared to some later C4 years, and any C6 is a POS  confirmed by what it would sell for. I couldn't trade it straight across for a 3 year old Hyundai.

In case you can't tell yet, I'm not a Corvette owner that owns one because he wants to say he owns one, or be seen in it. IDGAF about any of that. I bought mine because it was such a quantum-leap in technology from the 82. Sure, it got a lot of looks when it was new. Especially with my 24 year old lady friend at the time driving it.  But that's not why I bought it. For a measly 29K delivered, when the two of our combined annual incomes were about 30K at the time, it was a financial stretch to own it. But we did it for the adventure, because it was a cool, nothing-like-it at the time car, and it was something we could share between us and it was a big part of our relationship for many years. And by chance, we never wrecked it, I never modded it, it retained all its original soft parts, and 27 years later it has only been driven 43K miles, only 4K of those in the past 17 years.

You are obviously proud of your 84. That's fine. I tell my story regarding how I happen to own mine to show that I have a very long relationship with mine.  And an emotional one at that as the girl that helped me buy it married someone else 10 yeas later. Sure I'm satisfied (maybe even proud) with my accomplishments with my 85.  But in most car-peoples' eyes, its a POS 85. Mine too.  And I'm OK with that. 

Long-live the POS early C4's. Then junk them, because they aren't worth much to anyone else.

Save the wave,
 DP

I also agree with #'s 1 & 2

Let's let the comment go, folks...Dave had an opinion, as does everyone. Perhaps it was just taken the wrong way, or whatever, but let's not keep it going....let's just have a polite discussion, and leave it at that..otay? 
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