T-top Lock Mechanism Question

[Jan Larsson]

So been looking for some spare t-tops to have sitting around just in case ... and you can imagine how hard it is to find some in the UK ...

Well I lucked out and basicly got 2 nice sets within a 3 week period and paid near to nothing for them ... anyway the tops are identical and have the same markings on the glass etc as my original TTA tops ...

Looking at the actual locking mechanism (pins) I noticed the 2 sets I got hold of have a slightly different style compared to what my TTA tops have.

The metal pin is the same, same length and diameter BUT on the TTA tops the metal pin have a plastic sleeve if you like that seems to be spring loaded and centers with the metal pin in the pastic thingis in the roof itself on each side.

Not tried my spare tops yet on the TTA but my question to you guys is what type of mechanism do you have on yours? Style 1 or 2 (style 1 is my TTA tops).

Anyone know if GM changed in 89 at some point as both my spares come from 1989 Firebirds .... I know early styles had a hook type mechanism but that was back in 82/83 ....

 

[72firebird]

I'm pretty sure mine are the first style. Are all of the ttops glass or all of them lexan? I'm guessing that they're all the same material since you said they have the same markings on them.

 

[Jan Larsson]

I'm pretty sure mine are the first style. Are all of the ttops glass or all of them lexan? I'm guessing that they're all the same material since you said they have the same markings on them.

Yep all of them are glass and have the identical markings as well as the mirror finish on the inside ....

Not sure if GM changed the at some point but like the idea to have a spare set I can use but got somewhat disappointed (to say the least) when I looked at them this morning ....

If you all can have a look would be much appreciated.

I will post over on the GTAsourcepage as well to see if there's a possibility they are form other year Firebirds ...

 

[WS6]

I think mine are style 2, without the sleeve. I don't know much about t-tops but I thought there were 3 generations of locking styles. Early ones with hooks, then our style with 1st design being smaller pins then 2nd style with the larger pins.

 

[Jan Larsson]

I think mine are style 2, without the sleeve. I don't know much about t-tops but I thought there were 3 generations of locking styles. Early ones with hooks, then our style with 1st design being smaller pins then 2nd style with the larger pins.

Any chance you could take a look and if they are style 2 (without plastic sleeve) could you take a photo of the female part on the body of the car for me to see if that part is the same or not just so I can be sure they fit properly.

 

[WS6]

Any chance you could take a look and if they are style 2 (without plastic sleeve) could you take a photo of the female part on the body of the car for me to see if that part is the same or not just so I can be sure they fit properly.

By all means, I'll take my camera up to the shop tomorrow.:drag:

 

[81DaytonaPaceCar]

Any chance you could take a look and if they are style 2 (without plastic sleeve) could you take a photo of the female part on the body of the car for me to see if that part is the same or not just so I can be sure they fit properly.

Hey Jan, mine are the non-plastic sleeve as well...a couple pics...with my car being an early build car, I'm betting that the sleeved versions are a mid year fix.

Ironically, I think this is the first time I've had the T-tops off...lol...

 

[WS6]

...

....

That's about .389 inches in diameter or 99 mm.
That goo is syl glyde synthetic grease to keep the chirping down.

But as you can see it's just a metal pin.

Mine is a lower production number too,473


...

 

[fast400]

Jan,
I think all of the 89 TTA's are style 2 (no plastic). It's pretty easy to convert style 1 to 2 though. I got a glass set years ago for my prior TTA....anyhow, I had to switch the pins over to make things work... I still have the springs and plastic end pieces lying around somewhere.

 

[Jan Larsson]

Thx Guys, seems like the part in the body is the same for both style t-tops ... I will try them on mine and see how well they seem to fit. Will also have to see if theres been a recall or change ordered issued at some point during the 1989 build year.

Mine is a fairly late TTA being no 1078 so maybe changed early 89 sometime?

Thanks for posting all the pictures, very helpful as I wanted to make sure I can use the spare sets if needed.

 

[Jan Larsson]

Jan,
I think all of the 89 TTA's are style 2 (no plastic). It's pretty easy to convert style 1 to 2 though. I got a glass set years ago for my prior TTA....anyhow, I had to switch the pins over to make things work... I still have the springs and plastic end pieces lying around somewhere.

Did you have to switch the pins in the t-top because they would not fit (the metal pins) in the plastic receiver attached to the car body on each side? On the pictures posted above it seems like they are identical to what I have on my TTA using the style 1 (as per my pictures) pins with plastic sleeves.

 

[fast400]

Yes...I switched the pins completely. They're different diameters even after the plastic is off. Unfortunately you'll have to pull the pins out of the old tops to use in the new ones.
I vaguely remember it being a bit of a pain...but not too bad.

 

[Jan Larsson]

Ok so took a look in the GM Parts and Illustration catalog and this is what I found.

The receiving end (female) attached to the t-roof body is the same parts for all 1984 - 1992 t-top cars.

The pin style locking mechanism without the plastic sleeve is the 1st design then in 1989 at some point (still to find out when) GM issued a 2nd design with the plastic sleeves they called "self centering mechanism" and I can see how this works having the large plastic sleeve with the conical end being easire and assist centering the t-top in place and the metal pin is showed in place and the plastic spring loaded sleeve is helping to center the t-top along the car (front-rear if you like).

The metal pin is identical in diameter (just measured both styles) meaning any t-top style pictured in the posts above will fit any TTA. However style 2 (with plastic sleeve will be slightly easier to install I guess).

So no real functional difference once installed on the car.

I'll see if I can find when during the 1989 production year this change happened.

 

[fast400]

Jan,
It was a long time ago when I did the 'glass' switch, so things are fuzzy:whistle:. I do remember though that the glass with the plastic guide around the pin wouldn't fit. I checked my garage last night and found the springs and plastic guides from when I performed the switch (years ago!).
I thought I had to switch the pins too...guess it was a long time ago.

 

[Jan Larsson]

Jan,
It was a long time ago when I did the 'glass' switch, so things are fuzzy:whistle:. I do remember though that the glass with the plastic guide around the pin wouldn't fit. I checked my garage last night and found the springs and plastic guides from when I performed the switch (years ago!).
I thought I had to switch the pins too...guess it was a long time ago.

Not sure why you would have to remove that plstich sleeve/guide and spring when the receiving end in the body of the car is the same for both types of t-top mechanisms?

I will try to fit the earlier style t-top to mine and see how well it fits.

 

[JSTTA]

Hi Jim, I have car 1240, my tops are lexan w/ vin etched in it so i know the are original, anyway mine have the plastic piece on them. I guess the later #'s were changed but who knows where the cut is. Good luck!:cheers:

 

[JSTTA]

Hi Jim, I have car 1240. Has original lexan tops vin etched so i know they were not changed, i have the plastic cover on mine. I guess the later cars have the diff. set up , but who knows were the cut off is?:cheers:

 

[Jan Larsson]

Ok, short update. Took a closer look on the car with both style lock mechnisms. And the 1st design (pegs without the plastic sleeve) have the pegs closer to the glass of the t-top (so the vertical dimension if you like) compared to the 2nd design (self centering mechanism) that I have on mine (later builds in 1989).

This means they 1st design will fit but the receiving end (female) on the car body would need to be readjusted to sit slightly higher, not tried this and wont do it until I actually need to use one of these t-tops

Anyway thought I'll let you all know.

Now I also understand how the 2nd design had to have the plastic sleeve and spring removed to fit where the receiving end in the car body been adjusted properly for the 1st design t-tops.