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Does anyone have pictures of the roll bar that Autodelta was installing in GTA's? I've seen many exterior shots that lead me to believe that they had a basic one that was used w/o removing the back seats.
 

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AutoDelta Roll Bar

Does anyone have pictures of the roll bar that Autodelta was installing in GTA's? I've seen many exterior shots that lead me to believe that they had a basic one that was used w/o removing the back seats.
Roman has an original bar that he is using to make a copy for my restoration. I will ask him to send me a photo. The bar has a rearward brace that attaches to the floor and can be installed without removing the back seat. It is not as strong as later half cage designs but it is what Autodelta installed on the GTAs in the era, and it worked for Rindt's car in the rollover.

Bob

1965 RHD Corsa GTA 1966 ex-Kwech Trans-Am and B-sedan Champion
 

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I have some from the AR Mueseum of a GTA Jr. Corsa that I took while there. If you would like them I will get them for you.
Does anyone have pictures of the roll bar that Autodelta was installing in GTA's? I've seen many exterior shots that lead me to believe that they had a basic one that was used w/o removing the back seats.
 

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Discussion Starter #4
Thanks guys. I think it would be best to post the pictures here so other people can use the pictures for reference as well.
 

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I think Italiancarguy meant Roll Bar is in the ****pit and not anti-roll bar or anti-sway bar.?.? Primarily because he mentioned the back seat being removed.
 

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The rollbar was made of 22mm diameter tubing and the feet were attached to the raised platform behind the seats. There were two rearward facing back braces, about3/4 the way up the main hoop, connecting down to the inner wheel arch. The 22mm diameter was told to me by Don Black.

David
02/A 613900
 

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Discussion Starter #8 (Edited)
So most cars ran the backrest portion of the seat only? i've seen quite a few period pictures of cars in Europe with the backrest still in.
 

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Roll bar/hoop

Based on a pretty original car in the shop here the main hoop is about 45mm in diam. and the rear stays are 35mm. They attach via tabs about 17 1/2 inches above the base of the main hoop and run back to the inner wheel arches pretty much parallel w/ the line of the bottom of the windows or about right angle to the main hoop. 22mm is way too small for anything. Modern cage specs (like those available from Sparco) use 50mm main tubes with 40mm stays.
 

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Don't have access to my car right now - so no pictures. However, the 22mm diameter doesn't sound right - that's under an inch. Rather that dimension may be correct for the backstays - they are skinnier - but not the main hoop which is close to 1.5". The material is fairly thinwall - it may be CrMo. I base that on the relative lightness of the bar and the sound of the metal.

The main hoop mount to the outer edge of the rear seat shelf and the backstays are almost horizontal below the rear side window line and bolt to the rear wheel well. The backstays themselves are bolted to ears on the main hoop.

The bottom cushion will fit if one gives it a good squeeze - it might stick up 1/2" in the middle as the seat tends to buckle a bit. I have seen some modified lower seat cushions w/ slight cutouts for the bar and then resewn to get a better fit. The rear cushion fits as normal.

I'll post a pic sometime in the future if nobody beats me to it.

Edit: So based on the above post I assume that the 22mm spec is for the rear stabilizer bar which was available in sizes from 14mm to 22mm with large ones often being run during the period of the cars.
 

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Now we are talking 1965/66 specs. Things were different then. I had a Renault-Gordini and for FIA races it didnt even need a roll bar. The 22mm spec was confirmed by Don Black, as I said, for the original rollover bar, which was an extremely simple affair.

David
 

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Anthony,

Sorry this took so long. Here are some roll bar pics of the factory AD GTA Jr. in the AR Mueseo. Hope this helps you!
Let me know if you need some more or other shots.




Thanks guys. I think it would be best to post the pictures here so other people can use the pictures for reference as well.
 

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In Period

Of course the GTA Jr's rollbar was of, at least, a 2nd or 3rd generation affair.
Not only was larger diameter tubing used, but the cross bracing was certainly a later development.

So it amounts to this. What is your period of restoration ? If it is 1965, then the simple 22mm hoop would be correct. If your time is 1970+, then a larger diameter cage assembly would be OK.

As I see it, creating/using a modern CAD/CAM rollcage in an historical car is like fitting a 1929 1750 Zagato Spider with disc brakes and a DVD player.

If however, you are building a replicar with no particular build-provenance, then CAD/CAM away and enjoy.

David
GTA, built 1965
Giulietta Sprint, built 1959
GTV6, never asked Archivo Storico
 

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Based on a pretty original car in the shop here the main hoop is about 45mm in diam. and the rear stays are 35mm. They attach via tabs about 17 1/2 inches above the base of the main hoop and run back to the inner wheel arches pretty much parallel w/ the line of the bottom of the windows or about right angle to the main hoop. ......
This photo might help.....
 

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