slickrock55

So i had a little un-nerving experience a few days ago. Giving a friend a ride, accelerating down a straight on-ramp to the freeway, my passenger t-top suddenly popped out, flew maybe 20 feet spinning into the air and landed in the grass at the side of the freeway. Astonishingly, the glass was not broken and just the fiberglass was chipped. I'm thinking to myself, idiot, must not have been latched all the way.

However, when i retrieved it, it was fully latched! It somehow managed to flip out of its restraints regardless. This is an 82, so it has the L shaped clips to keep the tops in, not the later pin-style.

The car makes somewhere in the 450-500 hp range (based on a 12.4@118 pass). Is this enough to flex the chassis and make the top pop out? Is there another cause i'm overlooking? Clearly this is quite unacceptable and i REALLY dont want it to happen again.

johnnyboy

iTrader: (3)

ABSOLUTELY that is definitely more than enough, i have a friend who had an 85 t-top car and the smae thing happened to him with a mildly modified 350 nothing near what you had, and another friend who had the same problem with a stock t-top car. do you have sfc's or anything to stiffen your chassis?

slickrock55

Yep, forgot to add I do have spohn subframe connectors.

This all may be moot - as i think i'm installing a S&W racecars 8pt rollbar that i got a good deal on within the next week or two (Although not the one with the f-body door bars ) Hopefully THAT should be enough stiffness to keep those bad boys attached.

Ever heard of anyone changing to more robust latches (the kind on convertibles come to mind) or some kind of safety strap?

2kflhr

iTrader: (1)

Seems to me if you had that much body flex you should also have some cracking going on with the body panels and seams breaking loose.

I could see some flex during a hard launch but not once the vehicle is rolling at 35 mph+.

AlkyIROC

My car has never lost a T-top

2kflhr

iTrader: (1)

[QUOTE=Stephen 87 IROC;3034701]My car has never lost a T-top[/QUOTE

I think it is more a latching issue, if it came unlocked it could have hit right and knocked into the locked position.

slickrock55

[QUOTE=2kflhr;3034937]Im starting to agree. I'll have to take a look at the latch mechanism and make sure its adjusted properly etc.

Guess i just wanted it to make too much power for the t-tops

Time2Fly

That is an excellent example of Bournulli's principle.

2kflhr

iTrader: (1)

I needed it dumbed down:

"The decrease in pressure simultaneous with an increase in velocity, as predicted by the equation, is often called Bernoulli's principle"

V8Rumble

iTrader: (2)

slickrock55

Very well might be. Obviously theres fast moving air above the car, and its already an area of (however limited) flow detachment. But the windows were open, and unless that served to "ram" air in and increase the pressure, i dont see how such forces could build up.

Possible though

Gallileo60

My modded out 84 Berlinetaa did the same thing during a 1/4 mile race against a same color, same year Vette.. (I won)...Im just glad there was no one behind me....The car started wheel hopping really bad, and instead of letting off like a normal person would have...Well you know....Anyway mine driver side top went airborne, and broke into so many little peices.....I did not get laid when I got home. (Wife was pissed)...Mine was a combo of body flex, and poor back shocks....This car ran low 13's..mostly an Edelbrock 350.....I quickly replaced the shocks, and did not have the problem again, altho later I did tie the subframes...

slickrock55

I wonder if maybe its an issue with the type of latching mechanism. I dug this up:

Fisher*
1982-1983
Factory Installed
LOF Gray 08 glass, plastic edge trim around 3 sides. Hook type latching system.

Fisher*
1984-Mid 1985
Factory Installed
LOF Gray 08 glass, plastic edge trim around 3 sides. Pin type latching system.

Fisher*
Late 1985-1988
Factory Installed
LOF Gray 08 glass, exposed glass edge on 3 sides. Door key also fits t-top locks.

Fisher*
1989-1992
Factory Installed
LOF Gray 08 glass or LEXAMAR acrylic. Door key also fits t-top locks.

Ive got the hook type latch, i wonder if the pin type latch help retain the tops better. Im going to take a look at it today after work, but does anyone know if the mounting parts on the roof can be swapped for a later year? I would like to get some lexan tops for weight saving purposes.