Back in 1974 Porsche was developing its turbo engines for the 911 model after the successful experience with the models in the 917/30 Can-Am. Based on the Porsche Carrera RSR 3,000 cc. developed the model RSR Turbo 2.1, which used Porsche 917/10 components, such as the brake system and the magnesium wheels, and from 908, which used their front oil cooler. Aesthetically one its hallmarks were the flared wheel arches, particularly the rear axle ones, which had no differential and reached 2 meters wide. It was also new the front spoiler with air intakes for cooling the brakes and the front oil cooler, NACA type ir intakes instead of the rear windows, a raised rear window (solution used again in the 935 K3 and Baby ) and the huge rear wing with more NACA type air intakes to provide air to the KKK turbo installed on the engine which could sometimes could be seen when the car ran without the rear cover of the engine.
The 2.1 liters engine with a turbo blowing at 1.4 bar provides 500 hp. to 7600 r.p.m., power difficult to control given its solid rear axle.

As be a model don´t developed from a mass production car in the competitions of that years it had to compete in the category of prototypes, which clearly left him at a disadvantage compared to other prototypes developed expressly for the category, as could be Alfa Romeo or MATRA cars.

During the 1974 season the car achieved two second places (Le Mans and Watkins Glen) that made Porsche win the third position in the world manufacturer championship that year. The car I´m going to reproduce is that who took second place in the 6 hours of Watkins Glen in 1974, driven by Herbert Muller and Gijs Van Lennep. Here are some pictures:

And here another one running at Watkins Glen:

During long time I had at home a resin body kit (bodyshell and water decals) of this model stopped in the drawer. When I decided to make this car already had the experience of turning a body of 911 Altaya to a 935 (on the side menu you can see step by step of building the model by clicking on the link "Porsche 935 Mugello 6 hrs." ) what made me see the resin with different eyes, in other words, I didn´t like it. So I decided to transform a body of a Altaya Porsche 911 SC in a 500 hp monster.
The first step, as always, to immerse the body in alcohol to remove all paint. After leaving it clean, I began to paste epoxy putty

At the front I stuck evergreen plastic strips to the bumper, and was shaping the fenders with wood sandpaper, which is very useful at the start of work to lower the excess of putty.

As I didn´t need the rear spoiler for the model I was building I cutted completely, and also lowered by sanding what would be the front bumper of the model giving the same fall that the hood, as the RSR turbo bonnet fall reached the end of the front bumper. To appreciate it, here is a photo of the original car extrated from the web page http://atspeedimages.com

and here some of my scale model:

In previous scale cars I´ve been doing I have learned some things, and one of them is to plan the work before make it in order to do it faster and better. My intention with this car was to make it following a plan, so once done the "heavi" work I started to model the car from front to back, so the first thing is to work the front bumper. First, draw on the body position of the different air intakes:

and then opened using a mini drill with a 1 mm. diameter drill. The aperture is then adjusted with the file:

The air intakes for the brakes I've been drilling with drills getting thicker until a 2.75 mm diameter. which is practically as the EXIN Porsche 935 air intakes have. The rest of the shape I gave with a half-round file, which finished off with fine grit sandpaper. The result:

Before gluing the bottom edge of front bumper, and not to bother for the rest of the work, I molded the wheel arches, first the front, with special attention to the symmetry, rather complicated task indeed ...

and then the rear ones:

An overview of the car:

While I was waiting to dry for the putty stuck in the wheel arches to achieve symmetry I took to close the rear windows. We need the help of the bodywork of the Porsche 917 Fly Car Model already used in construction; 935 Mugello, which has a NACA type air intakes that perfectly fit the needed. First cut out of cardboard the shape of the window and then draw them on the body of our donor:

I trimmed the windows and give the appropriate shape:

which then are glued to the body using bicomponent glue so that they are properly secured:

As because I have given a thousand turns to this car and to the different models and versions of it there was something that didn´t suit to me ... until I realized. In the EXIN model (and thus in the Altaya model) the front bumper is not well shaped, excesive square and long, and so I reproduce it because to did it I had followed the contour of the front bumper to paste the evergreen strip. And taking the opportunity that didn´t convice me the openings for cooling the brakes and I´m went too far with the file I shortened the length of the nose of the car filing it.

To modify the openings and the shape of the nose of the car I hit a strip of evergreen 1 mm. thin then sanded to give it the right shape....

With the nose of the car working well under way I went to the rear. The spoiler of this car, along with the massive rear wheel arches, is the most characteristic part of the car so I would have to tune fine when doing so. To this I helped me with a template I made from the resin body kit of the RSR but adjusted to this model:

After several tests with plastic sheets I got to made a more adequately shape to the rear wing support that pasted to the car with bicomponent glue.

The wing support was larger than necessary with the intention to adjust later. And it was provisionally stuck, because of its complex thus was easy to handle.

One of the "problems" that have to take a long time to finish a scale model car is that the more you look the more bugs you see bugs... And if to this we add that occurred to me to use graph paper to check the symmetry it follows that before to make progress I preferred to left the work done so far well finished. The front wheel arches virtually didn´t need retouching, just a bit of sandpaper on the inside and outline a little the edge. To the rear ones the story was different as they were quite asymmetrical. First I stuck a couple of evergreen strips of 0.3 mm. thickness of the interior of the wheel arches:...

...and then with sandpaper I corrected faults (width and symmetry), using graph paper as a guide:

And compared with the photos a hobby mate gave me the result was not bad at all:

I did not look back much more in case I went the whole hog and began to retouch it again. Here you can see how they have been seen from behind:

With the rear wheel arches almost finished I returned to the car´s front. As discussed above, the length I had left was overdone so I shortened it to about 2 mm. and gave him a more rounded shape at the ends. I also changed the placement of the brake cooling air intakes that had previously left poorly positioned:

Make the opening of the radiator and air intakes of the brakes was something relatively quickly. The only difficulty was to left them the right size and well positioned. To this I helped me again of graph paper and I opened them slowly, carefully adjusted.
To finish the front bumper of the car only had to do what would be the spoiler, which has its intricacies, it consists of two overlapping planes, a small one around the whole front of the car from one wheel arch to another and larger one below it. So I decided to make two parts.
The upper part with a slim evergreen strip of 0.5 mm. thick glued with cianocrylate around the bumper, once stuck I defined it sanding very gently because I was stuck on an provisional way.

For the lower part I pasted another strip of the same material and thickness below the upper piece and the body, to have more surface to grab. At first the two pieces glued with superglue but then I made some small holes at the bottom which I introduced bicomponent glue as rivets to strengthen the joint.

The front part was nearly complete, some sandpaper fine-tuning and the radiator grille would do the rest, so I resumed the construction of the wing support. This time I brought up the task differently, first draw it on graph paper, and once get the correct shape and size los pase a pl´´astico was spent on plastic:

Now that was left a proper shape and height.

Once "solved" the problem of the wing support I started a very seriously work: the back grill. I had to do 28 holes of 1.5 mm diameter on a plastic strip of 24 x 10 mm, and so they were moderately aligned (I made them by hand) first stuck a piece of graph paper on the part to pierce.

Then, I was opening each hole with a 1 mm. diameter drill by hand, revise them later with another drill of 1.5 mm. The mini drill only was used to hold the drill, without plugging it, to do so more accurately.

Despite the care I put, they weren´t very well aligned, shall we say...

So I remade the piece again, this time marking points with an awl to drill so they were better aligned:

The above is the first one and the bottom is the piece that I just had done. Is obvious that the result was considerably better. Then put it in its place:

As you can see to mold right the wing support and leave as regular as possible I pasted a bit of putty. Once sanded the putty I marked the position where I had to open the hole to place the huge intercooler fitted in this car, previously I had taken the dimensions from a photo of the rear view of the car that I found helpful.

I carefully opened the hole using a mini drill and a fine drill:

The grid I made from a strip of evergreen from 1 mm to the stripes that mark the radiator with a triangular file: La rejilla la hice a partir de una tira de evergreen de 1 mm a la que marqué las rallas del radiador con una lima triangular:

which placed looks this way:

Continuing to work on wing support, did the air intake on the right. I first get an air intake that was consistent in size, in this case one from a Altaya Porsche 935, which I reserve for another occasion, as they say the cooks.

We mark the position of the air intake on the car:

and cut out and paste the piece, first with cyanoacrylate and then with bicomponent glue, to make a firm joint:

The wing NACA type air intake I made from scratch because I did not find any one so large that fitted well to the car, made with evergreen strips and the cap of a soda bottle to simulate the radiator.

First pasted the pieces with cianocrylate and then I reinforced with bicomponet glue:

This is how the piece was superimposed in its place:

The result doesn´t convince me, because that the cap stripes were a bit thick, so I used the simulated grid from a Audi TT Ninco chassis which were much thinner. At full view is that look much better:

I also changed a bit with putty the bottom of the rear wheel arch:

I pasted the evergreen piece that set the wing support with bicomponent glue. The pencil marks serve me as guide to find out where I had to cut the window and small air intakes:

At this point, I resorted to a "friend" that would indicate me the exact shape of the rear window and also help me in making the rear wing. Here I introduce him to you, the 1/18 scale model of the Porsche 911 RSR by AutoArt. A superb reproduction in every way.

Thanks to the scale model I was on safe reproducing the rear window and especially the rear wing, which was one of the parts of the car that wanted to left well reproduced.
I opened the back window to go finishing parts of the car.

Also fill the gap of the air intake with a little bit of wood restorative putty.

The wing shape I took it out of the rear wing of the 1/18 scale model, drawing it first on graph paper and then cutting it into a piece of evergreen than 1 mm. The photo also appears the drivers seat made of 0.75 mm. evergreen piece.

To give shape to the bottom of the wing used more restorative wood putty, which by its light weight is ideal for these cases. With fine sandpaper glued to a wooden block was giving it the right shape.

And with other pieces of the same plastic of 0.5 mm. I formed the sides of the wing. Those seen in the photo are the best I left after several that did.

... which glued looks like as follows:

The sides of the wing, had complication, because they consist of a plane, and a bulge in it. To simulate it, I made an evergreen piece of the same shape but smaller:

To then paste a bit of putty to give it a embossed shape:

So after a few hours were lime and sand,...

... and once attached:

I also sticked a bit of putty at the top of the wing that had not been a continued decline.
To continue the work I outlined the rear window using evergreen strips of 0.3 mm. thick glued to the edges.

Within the previous plastic strips stuck other than 0.5 mm. thickness that will be the support for the glass:

The shape of the body at the bottom of the window I hadn´t reproduced well, it was rounded drop sideways and I had made plain. To adjust it, used wood putty that was sanding to give the shape:

The small air intakes was cloned in poryuletane resin by Juan, partner of the forum "Los Petiflauticos" from a Fly Car model Porsche 917 body. I give him thanks for the air intakes and the lesson of cloning that gave me.

We make a hole in the place they will be and stick down with bi-component glue:

To go finishing, one coat of primer will help me to show faults and to finish the mold of the bodywork:

While it dried, I improved a little the interior to make it more accurate to the original model, with plastic strips and evergreen pipes:

And to finish the interior, cutted the glass to fit it into the body:

To the bodywork left to do the marks to bumper with a needle:

And retouch up the rear air intake that was pretty bad. It is remade with strips of evergreen stuck with bi-component glue, like the piece that goes over the air intake:

Of the remaining details of the bodywork, it last the front radiator, made with a "shadow mask" of a TV:

and mirrors are made from a resin ones to which drilled to paste a piece of plastic rod.

And while I finished the details, painted the body in silver because it is a paint that shows very clearly the failures.

....to be continued....

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