Page 1 of 2 12 LastLast
Results 1 to 10 of 19

Thread: Development of 901 Convertible, Prototyp 13360 (built 1964)

  1. #1
    Senior Member 911T1971's Avatar
    Join Date
    Jul 2006
    Location
    Switzerland
    Posts
    2,803

    Development of 901 Convertible, Prototyp 13360 (built 1964)

    Re the 901 Convertible - Prototyp Chassis 13360 - I recently read an interesting article by German Journalist Wolfgang Blaube who posted it on a swiss website.
    http://www.zwischengas.com/de/FT/fah...?teaserindex=1

    I first thought that they will repeat infos I read elsewhere (plus a few faults..) but actually it confirms many infos published first by Aichele's book published 20 years ago. Aichele description is still the most detailed literature about this theme.

    BUT the interesting part is however that this new article reports a few infos unknown to me and - I beleive until today - have been never detailed in any literature about the 901/902 development. It cites several employees of Reutter and Porsche, some have been interviewed by Aichele before, some never.
    Here is the text freely translated from german to english (I shortened it a bit and corrected google translator).

    ---------

    The mysterious forerunner - the 901 Convertible of 1964 (and his successful successors).


    « What is so special about the 1964 901 ancestor of the fully open 911's, which came finally on sale in 1982?
    Why it was not immediately produced? And did 13360 had an influence to the 911 Targa, the variant which bridges the long convertible-absent Porsche time period ?".

    Before it comes to these above issues, the history of the open-air Porsche 911 is often told like this: When the factory developed the 356 successor 901 in the early 60ies, in the US all convertibles were treated to be banned by future safety laws, initiated by the influential consumer advocate Ralph Nader. In response, Porsche anticipated the full convertible ban in their core U.S. market: the legacy of the successful 356 Cabriolet would receive stable roll bars and became the 911 Targa - the first security convertible in the world.

    Sounds as logical as romantic. But it is wrong.
    1st: Neither Nader nor anyone else at that time (early 60ies) talked about a possible convertible ban.
    2nd: in the last years of 356 production, the sale of 356 Cabriolet was so unsuccessful that the actual development of the 901 took place without any consideration of an open version.
    3rd: the official factory version of rollover protection for an open 901 lead them to a Targa bar is wrong and that it rather was the embarrassing solution of a technical compromise.
    Words that provoke and proofs are needed. Reboot for the real story:

    Upheaval and cost pressure for Porsche

    When Porsche outlined its next-generation sports cars in the late fifties, the company was in transition. The need for improvement in performance and road behavior required a further position away from the usual Volkswagen-based technology.
    At the same time the growing influence of the third-generation Porsche brought fresh air - and unrest among the old grandees. Ferdinand Alexander "Butzi" Porsche is named Head of Styling while Erwin Komenda is relegated to second in line, even Komenda was -since the late 30ies- Chief of Design&Konstruction bureau. Later Butzi’s cousin, Ferdinand Piëch replaced long-time race director Huschke von Hanstein. This upheaval in the house of Porsche produced fierce arguments over how the 356 heritage car -the 901- should look and what technology would be fitted to the new car.
    The 901 is also more demanding during the design phase and therefore much more expensive to develop. Increasingly, questions were posed which 901 parts could be produced less expensive all while schedules were getting tighter.

    Beloved 356 Cabriolet ?

    In 1962, radical cost cutting for the 901 development were defined - including the courageous decision to kill the open 901 variant completely. Reason for this were also the sharp decline of sales of open 356’s. In 1960, 356 convertible sales were 41.6 percent of total production, in 1961 they fell to 27.2 percent and 1962 fell further down to 19.8 percent, further decline was expected. In 1964, -the last full 356-year- only 1745 of a total of 10312 cars built were convertibles: a meager 16.9 percent of total number of units.
    And, in a clear contradiction to current literature, the often cited status of the «coveted 356 Cabriolet » can be now questioned : Often it is said, open 356 were a 35 percent of sales. But this reflects only the final year of 1965, which ended in September. From April 1965 on, the 911/912 Coupe were already off the production line and by end of 1965, 588 356 Convertible are built but only 1100 356 Coupes and also combined 9558 units of the new 911/912 Coupe's. In other words, in 1965, only one of twenty Porsche's built were open cars.

    Conceptional abandon of an open 901 version

    Above production/sale numbers speak for themselves. Nevertheless, the total abandonment of an open version of the 901 sounds today incredible. Especially why reasons were never officially transmitted. But the memory of some 901 body developer is intact. "In addition to the Coupe there was no other body structure part of a discussion," says Sylvester von Sass (81), responsable as a designer for the 901’s doors and hood at Porsche’s prototyp builder, Reutter. Its predecessor, the enthusiastic convertible fan Reinhard Schmädicke (79), underpins ". Butzi told me quite clearly that no Cabriolet is planned." And Erwin Komenda put it even more clearly by saying that he was "fundamentally opposed to any unnecessary hole in the body."
    Nevertheless, in the second half of 1963, there were several conceptual plans created for a fresh-air-901. For cost reasons most use the Coupe’s doors including their window frames. But no decision to actually built such a car were made.
    The fact that there was finally deciced to build one - a decision made in June 1964 , nine months after the debut of the 901 at the IAA - was due to the marketing people. Ferry Porsche's nephew Harald Wagner (now 90), 1954-1988 Head of Sales Germany and the largest convertible supporter had not given up: finally, evidence for a new convertible sales boom are reported from the USA.

    The first 901 Cabrio built in 1964

    Karmann immediately begins building a prototype.
    On 2 September 1964, the Porsche's factory production planning for the period 1964 to end of 1965 is defined: 5000 closed 901 and 902 Coupe and 1000 «open cars». Eight days later, on September 10th, Karmann provides the first convertible prototype, chassis number 13360 to Porsche's testing department, delivered without any roof construction.
    This was planned to be done in Zuffenhausen by Porsche convertible specialist Gerhard Schröder. He worked before in Cologne at Convertible manufacturer Karl German and after 1952 at Ramseier (Body work Worblaufen, Switzerland). Shortly afterwards he landed at Karmann where he was responsible for the VW Karmann Ghia Convertible as well as the Beetle convertible by Karmann. Finally, in 1956 he joined Porsche.
    There were neccessary changes to be made that would make the 901 Coupe enough rigid for a convertible. For Wolfgang Eyb (89), then head of the 901’s body structure, it was a hopeless plan: "If a car will be configured in an open and in fixed head version" you "build only the open version and then the closed version is based on it. Since the basic structure of the 901 was provided for only a Coupe, we then should have done it the other way around - which was impossible. Stiffness of the 901 convertible was always inadequate".
    Eugen Kolb (77), a then young engineer in Schroeder's team, gives an idea of the dilemma: "We even called the designer Fritz Martin back from the retirement and let him draw and calculate for two weeks.
    At the end he said: "The open 901, you can forget. After many desperate stiffening tests at the factory we finally tried an idea that was thought out in 1963 but initially hacked as the team felt it was the "aesthetic’s worst case" but technically the only realistic compromise: the "firmly welded roll cage"."
    Last edited by 911T1971; 01-16-2016 at 04:56 AM.
    Karim / Registry member No.773
    www.karimnoureldin.net

  2. #2
    Senior Member 911T1971's Avatar
    Join Date
    Jul 2006
    Location
    Switzerland
    Posts
    2,803
    Targa as a "worst case"

    While some at Porsche thought again the factory could do it without an open car, Harald Wagner started to accept - even with great regrets – a compromise version. If the car holds together: "At the 7000-kilometer journey under load on the VW test track, even pre-production chassis of the 901 Coupe versions broke and had to be reinforced…" the long-standing sales manager recalls.
    At a sales conference at Cologne Porsche dealer Fleischhauer, sales dealer Walter Franz proposed to create a separate term for the new typ of a half-convertible. Shortly thereafter, the word Targa falls - as reminiscent of Porsche's success at the Targa Florio. Only later Wagner discovered that targa means "shield" in Italian and the idea of a roll bar as a safety marketing argument is created: the rest is history: soon the model name Targa is a global valid synonym for the responsible type of open-top car driving.

    Attraction at the Geneva Motor Show

    In March 1966, the Porsche Targa is presented at the Geneva Motor Show. The Swiss Newspaper «Automobil Revue» dedicates its newcomer an extensive section:
    «Porsche calls the new open body style Targa. Particular strength of this design is the fixed to the body mounted roll bar for increased safety, for the very first time in a mass-produced vehicle... »

    No safety concerns for convertibles in the U.S.

    And where is Ralph Nader ? The U.S. consumer advocate who published in 1965 his legendary book "Unsafe at any Speed", did lash out lousy car suspensions and possible injuries of joyful car interiors. But the lack of convertible’s security, he said not a single word. Only in 1968 the topic started to be discussed in public and quickly became a general political issue. But at the time, the 911 Targa was a long time established.
    Would it have been earlier discussed in the US (and it was not) especially Mercedes-Benz would have reacted, as the US- market oriented "Pagoda" 230SL debuted in 1963, simultaneously with the 901.
    But not even MB’s Béla Barényi, inventor of passiv safety at MB, saw a need for such. Ex-Reutter Reinhard Schmädicke who joined Daimler-Benz in 1962 and was responsable for the 230SL, agrees: "We talked about windscreen frames without visual disabilities, secure door locks but never ever over rollover protection."

    The rediscovered 901 Cabriolet

    Meanwhile, number 13360 and Porsches only 901 full convertible prototype lies in a corner of Karlsruhe's dealer Freisinger, its in a sad state. (editor's note: the car was used as a test bed until 1966ish and received in the process Fuchs wheels). Until it was finally freed by Mr. Myron Vernis, Ohio, in 2001.
    This Porsche 901 Cabriolet prototype of 1964 foreshadows the design of the 911SC convertible, which was about to be built by Porsche 19 years later. Myron buys the 901 prototype in exchange of a non-matching 356 B Carrera GS (profane boxer instead of expensive four-camshaft heart in the rear), valued around $ 100,000. "My friends thought it was stupid because then an early 911 was just an old car".
    Myron laughs and has reasons: This object ‘s value has increased tenfold in twelve years.

    Still without a roof

    However, this increase in value, he says, is more of a hindrance when it comes to drive the unsheltered 901, "you can such a thing hardly park and leave somewhere," sighs Myron and picks a piece of crumbled foam from the empty top neckline .
    The owner of this unique 901 were the factory once tried all possible folding variants including a fixed Targa bracket, likes above image very much.
    But as an inspiration for an upgrade for his collector item he refuses and answers - with a purely rhetorical question:
    "If you would have the only open Porsche 901 in the world, would you ever drive it closed ?"
    Last edited by 911T1971; 01-11-2016 at 01:31 AM.
    Karim / Registry member No.773
    www.karimnoureldin.net

  3. #3
    Senior Member 911T1971's Avatar
    Join Date
    Jul 2006
    Location
    Switzerland
    Posts
    2,803
    Here is the car in Germany prior to the sale to Myron.
    This is coming off the Aichele book, he states it was for sale since 1993 by Freisinger.
    Last edited by 911T1971; 01-16-2016 at 04:56 AM.
    Karim / Registry member No.773
    www.karimnoureldin.net

  4. #4
    Senior Member
    Join Date
    Oct 2008
    Location
    Burford, ON, Canada
    Posts
    3,203
    Wonderful history!
    Porsche Historian, contact for Kardex
    Addicted since 1975, ESR mbr# 2200 to 2020 03
    Researching Paint codes and Engine Build numbers

  5. #5
    Senior Member
    Join Date
    Nov 2003
    Location
    Santa Monica CA
    Posts
    1,668
    Great history-- but somehow I like the looks of the Targa better. The cabio looks incomplete to me. Chris
    1. Chris-Early S Registry#205
    2. '70 911S Tangerine
    3. '68 911L Euro Ossi Blue

  6. #6
    Senior Member 911T1971's Avatar
    Join Date
    Jul 2006
    Location
    Switzerland
    Posts
    2,803
    13360 at Pebble Beach 2013, along w 901 Prototyp 13327 "Barbarossa".


    At the 901 Convertible, one can sense the very large opening of the shell, which then gave the factory so much trouble in structural rigidity. Contrary to the similar aged 2-seater MB 230SL "Pagode", the 901 is in size almost a 4-seater convertible.
    According to Aichele "a factory team meeting on June 12th 1964 concludes that to make the 901 "open car" structurally rigid, one should change the 901's rear area including engine compartment. It was decided to abandon due to too much and too high costs of tooling/construction changes to the car's body".




    New calculation methods, better manufacturing developments and stronger chassis materiels led to the presentation of the official factory 911 Convertible/Cabriolet, here in 1981. (source Blaube)
    Last edited by 911T1971; 02-07-2014 at 12:32 PM.
    Karim / Registry member No.773
    www.karimnoureldin.net

  7. #7
    Senior Member
    Join Date
    Jul 2008
    Location
    Holland
    Posts
    281
    Quote Originally Posted by raspy2point2 View Post
    Great history-- but somehow I like the looks of the Targa better. The cabio looks incomplete to me. Chris
    The design mistake Porsche made with the open 901, is that they kept the sheetmetal behind the door too big an area.
    Look at the open 356, less over there, hence proportions way better...
    Slate Gray, Red Leather, 1968 912 HWT

  8. #8
    Senior Member
    Join Date
    Jul 2008
    Location
    Holland
    Posts
    281
    Quote Originally Posted by varunan123 View Post
    isn't a targa really and afterthought to a cabriolet.
    Afterthoughts are better...
    Slate Gray, Red Leather, 1968 912 HWT

  9. #9
    Senior Member 911T1971's Avatar
    Join Date
    Jul 2006
    Location
    Switzerland
    Posts
    2,803
    Quote Originally Posted by raspy2point2 View Post
    The cabio looks incomplete to me. Chris
    901 prototyp 13360 does missing its top and is kept as is by its current owner.

    Once the 911 has its convertible top, imo it looks alright.
    Aichele writes, that at one point in 1965 the design team thought to lower the 901's front windshield.
    This would give the 911 Convertible much better proportions.
    The 1989 911 Speedster later just did this…Imo a beautiful shape.

    Last edited by 911T1971; 01-16-2016 at 04:57 AM.
    Karim / Registry member No.773
    www.karimnoureldin.net

  10. #10
    I love the Speedster with the roof up, all other Targas and cabriolets I say no thanks. I'll take a coupe. If only the coupe had the look of the Speedster. It has that pre-A look where the roof comes down before the windscreen starts. Looks very serious.

    Max_911S_fahrer, on Flickr
    1971 911S, 2.7RS spec MFI engine, suspension mods, lightened
    Early 911S Registry Member #425

Similar Threads

  1. FS: @classicdriver - Porsche 928 CS S4 Clubsport Prototyp ex Hans Joachim Stuck
    By 67er911S in forum For Sale/Wanted: Other Porsche Cars and Parts
    Replies: 8
    Last Post: 03-31-2014, 02:09 AM
  2. Prototyp Musuem (Hamburg)
    By obrut in forum Drives, Tours, Gatherings, Racing and Adventures
    Replies: 5
    Last Post: 11-29-2011, 06:21 AM
  3. A real '64 prototyp?
    By amsterdamned in forum For Sale/Wanted: Early 911 Cars, 1965 - 1973
    Replies: 4
    Last Post: 01-31-2010, 03:56 PM
  4. development of the ducktail
    By HughH in forum General Info
    Replies: 50
    Last Post: 07-18-2009, 10:39 PM
  5. New development in the F1 spying case
    By Cornpanzer in forum Off Topic
    Replies: 1
    Last Post: 07-30-2007, 06:41 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Message Board Disclaimer
This is a public forum. Messages posted here can be viewed by the public. The Early 911S Registry is not responsible for messages posted in its online forums, and any message will express the views of the author and not the Early 911S Registry. Use of online forums shall constitute the agreement of the user not to post anything of religious or political content, false and defamatory, inaccurate, abusive, vulgar, hateful, harassing, obscene, profane, sexually oriented, threatening, invasive of a person's privacy, or otherwise to violate the law and the further agreement of the user to be solely responsible for and hold the Early 911S Registry harmless in the event of any claim based on their message. Any viewer who finds a message objectionable should contact us immediately by email. The Early 911S Registry has the ability to remove objectionable messages and we will make every effort to do so, within a reasonable time frame, if we determine that removal is necessary.