(Teo’s Zuffenhaus-built, IROC-inspired 911 – photo credit:Matt Howell)

Special Projects

While not a literal translation of ‘Zuffenhaus’, Special Projects could be considered its synonym – since our build shop opened in 2005, Zuffenhaus has been establishing itself with innovative and custom design work.

In addition to our and Porsche restoration experience, we rely heavily on our Celette frame benches during our projects – from installing flares to large-scale structural changes (the 964 floorpan transplanted into the 1974 911 pictured above, for instance) ; the Celette is required to verify chassis position and dimension for quality results.

If you’re considering altering your 911, here are some of our most-requested services:


The iconic long-hood 911 of the late 1960’s and early 70’s continues to grow in popularity among Porsche enthusiasts, in step with the international affinity for vintage automobiles and accoutrements.

For the 911 enthusiast, the long-hood era represents Porsche heritage – a period wherein the company distinguished itself and its racing pedigree – a period that saw the genesis of the designations R, T/R, S, S/T, RS, & RSR.

As the original cars increase in collectability, more and more people desire the aesthetic and lightweight feel of the long-hood era, but with the usability and performance of later Porsche cars. For that special combination, backdating an impact bumper era 911 (74-89) or 964 can provide the experience of the early 911 with the benefits of a modern platform.

Zuffenhaus was an early leader in quality constructed, accurate all-metal 911 and 964 backdates in the US; and we’ve grown our capabilities since – including the creation of our own backdate-oriented product line.
SC, Carrera, or 964 Porsche; regardless of your starting point, we have an established, details-oriented backdate plan for your application.


Minimizing the potential of head injury is a cornerstone of any safety system, whereas relocation of weight lower in the chassis is a basic principle of sports car design; we address both by lowering the seat mounting structure in a 911, and consider this a standard part of special project work.

G Model:
We lower the seat mount in 1974 and later 911s by removing of the factory seat mount structure at the spot welds and replacing it with a welded steel structure positioned 50mm lower in the chassis, angled according to the factory mount.

The new mounting assembly is considerably stronger than the original and will accept both Sparco-style sliders and OMP-style, FIA-approved side mounts for composite competition seats. Competition vehicles with only a driver’s side seat can use passenger side as a strong and convenient mounting point for cool-suit reservoirs, fire-suppression bottles, or other in-cabin accessories.

F Model:
For 1973 and earlier 911s we make RS lightweight seat mounts, modeled after the historic 911RS crossbars and designed for 30mm reduction in seat height.


While relocating weight in a sports car is beneficial, removing forty pounds from the highest point of the vehicle is a significant improvement. Considering that removal of the sunroof cartridge also adds precious inches of protection above the driver’s head and mitigates the classic 911’s tendency to rust from sunroof drain failure, it is not hard to understand why sunroof deletion is a popular request among our clients.

Deletion methods vary, but for air-cooled 911s our preferred method involves grafting a donor roof from a non-sunroof 911 on the client’s car. This method requires minimal finishing work before painting, and with the use of a proper windshield fixture ensures 100% accuracy of factory roof contours. On the other hand, deletion on Porsche’s water-cooled 911s is the most straightforward, as the factory deletion panel is simply spot welded in place after removal of the original roof section.


Porsche first used this alteration on the 935, creating the historical precedence for deleting the drip rails on the 911.

There are multiple benefits to removing the drip rails on a 911: reduction of wind noise and aerodynamic drag as a result of shaving the A-pillar portion (particularly when coupled with mirror deletion); reduction of lift and an increase in rear wing effectiveness results from the absent C-pillar portion; and the cabin’s rigidity improves by virtue of the welding involved.

The drip rail is actually composed of 3 different panels, folded together to form the rain gutter and attach the roof to the body. We remove and tack-weld the drip rail in sections, finishing with a continuous weld seam between front and rear cowls on each side of the roof. As the panels aren’t typically co-planar, deletion involves adjusting the relative heights of the roof and body panels to allow them to meet at the weld in a single plane.

The result is a smooth aesthetic change with aerodynamic benefits.