Found this here pretty cool car this Progetto GTV

Part 1:

Since I am going to use the car in racing a roll cage is an important part. Not only does it improve safety but it also improves the stiffness of the car, depending on how you build the roll cage off course. And the

FIA article number 253

about safety equipment tells you all the rules around how to build a roll cage safe.

So after searching around the net for different roll cages for my car, I found out that there where only 4 and 6 points roll cages. 2 points for the rear towers, 2 points in the rear of the doors and if 6 points, 2 points in the front of the doors. But I wanted something more, since most of the problems on these cars is in the front I wanted to make an 8 point roll cage, adding 2 points for the front towers. This will most likely stiffen up the front quite much, and making it strong enough so that I can run coil over only. The other thing that I wanted to do was to make the roll cage a demountable roll cage, this didn�t seem to be any bigger problem to make than to just weld it. And it doesn�t make it weaker for that matter.

But there was problems making it an 8 point roll cage. First of all I don�t have any experience making roll cages and I never seen any GTV/6 with this either. So a lot of planning was needed.

So in the mean while I decided to continue and make the 6 point roll cage first. And take the front part in the end, and taking some experience with me on the way.

The first part that was set up was the main roll bar, and since that part was already bent it was just minor cutting needed to get it in place. And the mounting point that I used was 253-50, making it removable.

Then the rear lateral bars was cut and fitted to the rear towers, and mounted with method 253-57.

The method that I found out that was the best way to do it, was to take a piece of thin cardboard and roll it over the pipe to get the shape of the pipe, and then use that piece and cut that to shape it like I would do to make the pipe fit. Then taking it over the pipe, mark it where to cut and then cut it. By doing this I didn�t need to cut and grind the pipe several times to make it fit, but by easily cutting the cardboard many times and then cut only once on the pipe itself, saving a lot of time and grinding discs. And for the rear lateral bars I made a copy of the one side in the same way by using cardboard.

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Then I decided to go for a diagonal cross in the rear as shown on the 253-21, even though there will come one straight bar for the harnesses later. But first one straight bar was made then two other bars where made to make a cross.

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After that the front laterals roll bar where cut and fitted with one transversal member and attaching it to the floor with the same method as the main roll bar, 253-50. And the attachment point on the main roll bar method 253-45 was used.

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Then I decided to go for the door bars as shown on the method 253-9, looking like an X, and using the method 253-47 for attachment. Making it easy to remove if needed, and making the whole roll cage demountable. First I made the one straight bar starting from almost in the middle of the doors height at the rear and going down in the front. Then making the two other bars, but making it so that the X is lower in the front than the rear. The mounting point was made by solid 10mm steel plates that were cut out. And the other mounts I use rigging screws that I made some longer threads on so that the gap would be less, making it a little stronger. After one side was done I just copied the pipes with the same method as mention earlier by using cardboard.

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So far everything had been straight forward since the FIA rules tells you how it should be done, and that most of the cars fitted with a roll cage has either a 4 or 6 point roll cage, so that you can see on pictures on how others have done it. But now it was time to start making the last 2 points that was going to the front towers.

I looked at several ideas on how I could do this. What I used as a reference was just making ideas of things and places that I wanted to have. Like making the pipe hit in the middle of the tower and making it go as straight as possible back to the firewall. The problem was that I wanted it to go a little inside the wheel arch but the problem was that I didn�t know if it would come in the way for the wheel or not. After checking with another GTV6 I found out that I had around 30mm clearance, but after some more thinking and trying I managed to get the pipe another 10mm further up and 15mm further inn as you can see on one of the pictures, making the clearance around 40-50mm. So now the wheel will smash into the wheel arch before hitting the pipe.

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The towers where reinforced by making some 3mm plates going over it and welded it in place, and some tectyl took fire in the progress making a lot of smoke.

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At the firewall I wanted to use the method 253-52. So the first thing to do was to make the plate on the front side of the firewall, as you can see on the picture I used a pen marker to indicate where I needed to hammer and form the plate to fit the firewall. Next I made a copy of that plate and then I drilled a hole through them both in the middle and then a hole in the firewall, so that I could make them match. After that I made 4 holes that were needed to bolt the entire mount when done. Then the same thing was done on the other side. And then I welded the pipe on the plate on each side, making it the easiest way to get them in and in place, and then they where welded in place on both sides.

After that I cut the pipe that was half done to match this and made a copy of it for the other side, and then welded it all in place.

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Now the only remaining part was the additional reinforcement on the other side of the firewall also called a front suspension mounting points shown as method 253-25.

Four mounting point parts of the method 253-47 where then made, before I started on making the upper pipe first. Using the door bars end point as a reference for where the front mounting point should hit. After that the lower bar where made, before making a copy of the pipes for the other side.

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So now the roll cage was done, but only one big and crucial thing remained, welding the whole cage.

First I went over the whole cage making some more welding points to minimize the chance of the cage bending and twisting when welding.

Some know what I mean but some don�t. So what I mean is that when you are going to weld something like this roll cage for example you need some good welding points, because when welding for a longer period at the same time thing starts to get seriously hot so that the metal will twist and bend if not spot welded enough, and in this case it would make the whole roll cage unusable because it would probably don�t fit in again. But by spot welding a lot on the cage before you take it out would minimize the chance of this happening.

After this the cage was taken out and mounted in place on the floor before I welded it all. And once again I mounted it all to minimize it for bending and twisting.

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Now the cage itself is more or less done, the only remaining part is that straight bar in the back diagonal for the harnesses as mention earlier. And all of the parts needed for this are under way. When this is done I will come to a point that I have been waiting for I almost 2 years now!

And I must say that working on this roll cage has been great fun and given me some experience. And another thing as you may have seen on one of the pictures was those two bottles of welding gas. After a little research it surprised me to calculate that for now I have used welding gas for a total of over 700-800 minutes of constant welding on this car, with a usage of 17 liters a minute!

our rules are pretty strict too, we have to add alot more bars this year too with gussets.

Wow, nice job AJ! Quite a bit of calculation and measuring for sure.

well I didn't do any work yet, lol. That was some info I found for when I do start work on my own cage. I gave a link to the source at the top if you want to see where it came from.

By: AJ

well I didn't do any work yet, lol. That was some info I found for when I do start work on my own cage. I gave a link to the source at the top if you want to see where it came from.

I guess I looked over it to fast. Got carried away looking at the pictures, saw the red car and assumed it was yours.

yea I'd love to sit down and start doing that kind of work. I'll need to get something together since I have that racing seat I want to put in.