4th gen Firebird build, are "T Tops" a strength issue?
 

A customer is having me build a 4 gen Firebird bracket racer. Small block of about 700 horse, 6.0's 1/8 mile performance. Finished weight with driver around 2900 pounds.

The "core" car we are considering has T tops.

The buildup will be a back half with full cage.

Question, is there any structural problem building a T top car?

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

I would think not...lots of convertibles out there racing as well.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

a reasonable thought

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

Larry,

I think it is all how you tie the cage into the structure of the car. I have not done anything with 4th gen bodies, but most OEM floor structures are a little different for convertibles and T top cars.

With a full cage, and your experience, I would not worry about it at all.

Ken

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

The one issue I am considering now is the weight. Because of the added structure, is a T Top car of any consideration heavier than a non - T.

OR, would the extra structure be an advantage?

I know the tops themselves are heavy.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

Not sure about shipping weight. Could look at the NHRA guides and see if it shows a difference.

Not sure if customer wants the T top look, but I remember seeing a car long time ago that the guy had made metal covers to replace the glass. Do not remember any details, was long time ago. Sure this would take a lot of fab work, but might be able to do some aluminum covers and save some (lot) weight and still have structure. With cage in place and twist eliminated from car frame, would not need the OEM structure of the tops. Also rain/water leaks not as big a concern with race car?

Just some early Monday morning race car thoughts - when I should be working! LOL.

Ken

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

Pondering is a good and necessary thing.

"you keep thinking Butch, that's what your best at" [from Butch Cassidy and the Sundance Kid]

:)

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

After some pondering, I think we should find a ​non - T core car. We will be making an effort to remove all weight so no reason to have that handicap.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

A T-top car is an ugly creation to me, but for a bracket car I don't see it being much of a detriment.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

another thought for consideration,

we hope it never happens, yet if you get up side down, think about where will the T Top glass would go.

I figger some of it would be all over the driver :(

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

I built my 97 Firebird from a body in white . If the roof is off , the structure underneath is basically the same . A coupe has a metal piece that is spot welded across the side window opening . That part is not there on the T-Top cars . So the difference in weight is the T-Top itself . The roof on a coupe is just a thin piece of plastic that is bonded on the under structure . I agree, a well designed roll cage will provide all the structure you would need .

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

If we get a non - T core car can we easily remove the glued on top to aid in construction access?

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

I think its a poly urethane adhesive, which is really high strength . I would say there is no way to get the roof off and be able to reuse it . Are those roofs still available through GM ? I bought one years ago, but GM typically only has parts available for 5-10 years after the model goes out of production . Although they still sell fenders for Tri-Five Chevy's , I've been told .

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

I appreciate the ideas from everyone.

Thanks,

we are finding a non - T car and going to work :)

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

One of my street car go fast guys came by to look at my 94 Firebird that was for sale. Once he seen it was a T-top he wasn't interested as he stated 35 lbs heavier. Don't know how factual it is.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

My Firebird stocker was a t-top car and had a full stocker legal cage.

It was built by PK racecars in Ohio and did some pretty high wheelies and still does....

60' times routinely in the very low 1.30's and even into the 1.20's IIRC

There was never any evidence of flex...

I did not like that it was a t-top car but it made zero difference in how it worked.....they do leak water though as I left it outside for a while before I finished it......

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

You could save weight and run it with the tops out. I goes it would be legal with the cage, I know that Keith Mayers runs Super Street with his sunroof open in his Porche and it would make for good ventilation on those really hot days.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

Larry check your emails Dick

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

The tops can be removed and reused. I wouldn't say easily, but it can be done. As stated above the adhesive is very hard and similar to urethane. The black car I am running in super stock now was a t top car that we converted to a hard top. There is some structure where the top of the window would meet near the roof that has to be cut off a donor and welded in.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

Removing the plastic roof sail is fairly easy IF you use a wire saw like they use for windshields slide it under the part and start sawing back and forth thru the adhesive. Take your time cutting that piece is about $400 if you break it. It will come off just takes a long time to remove ut

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

I've built several Ttop Fbodies , but I will only do them with cages ,no problem with strength , easy to convert to full top with a donor car.
T structure under the roof is the same as a non t top car .
I do recommend wearing arm restraints with them and by the way running without them in place requires the use of arm restraints ,same as a roadster.

Re: 4th gen Firebird build, are "T Tops" a strength issue?
 

I was told about mine, by one of the most knowledgeable people I know and highly respect t not worry about mine.

Edit: They all are built with the same roof structure. Simply glueing that sheet metal front piece in place to cover the holes won't add measureable strength to the vehicle. That is all it is, a piece of tin, that is actually glued in place on the non-tee top cars.