Welcome to the 907K project section of newhistorics.com

Two 907K's have been underconstruction for the last six years. We are about 95% done now andhope to be testing one of them thissummer.These carsare not for sale. This project is a non-commercial, special interest, effort.

We will be updating this page regularly in the same chronological order that the project evolved. This may, hopefully, be the most complete record in existence of the faithful recreation (or creation) of one of these vintage racing cars. Our goal was to try to exactly duplicate all original manufacturing processes, fabrication methods, and keep the function and experience of the car identical to the original. Please submit any historical information, corrections, or comments in our guestbook. This documentation project is an open "archeology" historical effort as much as a hobby and passion and the more people who get involved, the more exciting it will be.

We believe there were eleven (?) short tail coupes originally made. Some may have been converted into 908 cars with new bodies. Any info on this is appreciated as we would like to build a list here of where they all are today. If you have a 907K, please visit our guest book. Perhaps we can provide you with spares etc.

These are intended to be 99.9% accurate and identical to the originals we examined exhaustively. Like the three 907's that won Datona in 1968, they will have flat 6 engines, not eights. The 907 frame was designed to accommodate either engine. We are sending letters to Santa Claus every year for two flat 8 motors. So far, no response.

This photo shows the two cars ready for engine installation and being wet-sanded and polished and receiving decals. Thousands of hours unfolded to get to this point.






We started working on a ground up 907K fabrication in 2003. The photo below shows some bodywork pieces behind a freshly painted frame. Original factory blueprints hang on the walls for ambiance and occasional reference. Notice how clean the floor is...no sanding yet. Frame construction is, by far, the most challenging aspect of fabrication, but assembling the bodywork to a frame is a very time consuming and perilous task. There was a lot of variation in assembly from car to car when these were new. They were all hand fabricated from start to finish. So this is how we had to do it.



While having bodywork in hand seems like progress, making a 100% original factory frame is a massive undertaking. I studied every known published resource,countless photos of 908 and 907 steel framed cars, and had access to a 907K and 908-02 cars to research small details like oil line fitting attachments and brackets. Making a frame like this is mechanical design archeology as much as it is a challenging test of a fabricator's skill and project management. The 910 frame was similar and a bit easier, so I was glad I had that under my belt. First step: get out the drafting tools and calculator and pour over the very hard to read original blueprints. It helps to read German, you don't want to confuse your "Vorn achse" with your "Hinten Achse".

Note:Anyone interested in the most fascinating account of blow-by-blow testing and historical engineering details should read Paul Frere's excellent book, "The Racing Porsches". He describes how ans where parts broke in testing. These cars were designed for very short lives indeed.



The first step in creating this car was to draft full size fabrication drawings on vellum and then transfer that to a 15 foot long frame table. A note to all you industrial welders out there: carefully welding very thin steel tubing using a TIG process, we avoid distortion and wooden tooling works very well. Generating full scale drawings were necessary as the original factory blueprints for the frame had discrepencies and did not scale. Drafting 1:1 scale drawings in several views also allowed us to verify the locations of all ball centers and brackets with very high accuracy; to check the design intention of all of the critical features of the frame. For the most part, the 907 and 910 share similar suspension geometry and we were able to cross check against the 910 blueprints. This was a satisfyinginvestigation of Porsche's design evolution.



A frame this complex requires significant planning ahead of time to divide it into logical and practical sub-assemblies. The entire rear section of the frame is one such sub-assembly and it features some very difficult to miter joints. Solidworks 3D mechanical design software was used to calculate the precise miter angles required to start this piece of the puzzle. The printouts shown below were the result of a day of head scratching...but I eventually got the magic numbers.




These prototype cars were designed to be as light as possible. Porsche took advantage of the frame tubes to carry hot oil. This requires that the very first frame sub-assemblies be constructed as oil lines with special metric fittings that will eventually host oil fittings. A dear friend, to whom we are indebted, gave us a selection of used, impossible to find, Argus oil line fittings. We were grateful for these rare jewels (note the little yellow gems). After this "oil line" was TIG'd up, I vacuum leak checked it to make sure we didn't get a messy and impossible to fix leak once the car was completed.




Back to the rear sub-assembly... Here we have a 3D jig ready to tack up the heaviest section of frame in the whole car. The rear suspension mounts substantially to this section. Every line is within 0.5mm and everything is checked for squareness over and over. Measure ten times and weld once! No grinding and re-welding required that way.



I used imported metric precision DOM tubing for the frame. All of the wall thicknesses are as specified on the factory prints - so there was no guesswork or engineering with finite element analysis required. This frame is just as fragile as the original - and light. Don't hit any potholes!



Some of the very critical suspension attachment brackets have complex shapes with compound curves. A hardwood hammerforming pattern is made and steel sheet is formed over the pattern. This process takes a lot of time, but the end product looks like press work that came from a steel tool.









Here is the installed bracket. This one locates the two lower inverted wishbones that attach to the rear uprights. Hollow titanium shear pins pass through the welded in bushings on each side. These were machined on the Hardinge Super Precision lathe and then reamed to final dimension within 0.0005 inches. All of the attachments to the frame are made this way and it is very difficult to align the double shear bores. Titanium galls badly in the alloy steel bushings, so great care and a little antiseize is used during assembly and welding.




Our friend Felmir came to the shop for a visit a few weeks ago. He is our only Porsche friend with his own engine dyno in his home shop. Felmir is a 911 engine builder extraordinaire! He also fits comfortably in the 907 and we are envious of this.

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The photos above capture several fabrication sequences: completing the rear section of the frame with upper rear link brackets, bending the horizontal windscreen hoop over a wood mandrel, integrating the oil line into the lower frame sub-assembly. Some tubes are machined with a hole saw jig to make the close fitting fish-mouth cuts. This only works for angles up to 50 degrees or so. Past that, iterative hand filing and sweat are required to make a close fit. The entire floor section is laid out on the bench and tack welded in place before the diagonal sections are added. Again, low heat and very careful fitting minimize errors to less than one mm for any tube position in the assembly.