Information needed for 1971 911's

[davep]

Greetings fellow members, and I really need help from all members with a 1971 911 or engine / transmission from that year. The primary puzzle I need to solve is why the published data for the 911S has fewer engines (1959) than combined 911S coupe and Targa chassis (2198 taking into account the the first ten of each model were reserved numbers). That is a deficit of 239 engines, and so far I only know of 11 race engines. That leaves a lot of chassis without engines according to factory figures. What are the missing engines?

So why do I want to know about the 911T and the 911E as well? The 911T had a surplus of 49 engines with a build of about 7963 chassis. The 911E had a surplus of 24 engines with a build of about 2003 chassis. The 911T & 911E shared the same Sportomatic transmissions, and there were 678 Sporto engines combined produced. However I only know of 473 of these. The Factory did not provide the end of the transmission serial # range for the transmissions, and I want to be able to come close to finding these data points. First, it is a nice set of data to have to complement the serial ranges for the cars and engines. Second, it can help to determine if there were sufficient transmissions built to match the number of chassis built. So far I am about 600 transmissions short of minimum required. My data on the 4 speed box and the Sporto box is sparse, so please scour the sheds and let me know details on all of them.

I cannot believe the Factory sold cars without engines, and I don't think that 240 or more race engines were built, so what were the missing 911S engines. The Sporto comes to mind, but the literature suggests strongly that the 911S only came with a five speed manual transmission. I am already short 200 Sporto trans, and another 200 or more would be unusual. I have collected a fair amount of data and would think that I should have come across a serial in the high range already. The 240 missing engines are about 11% of the total 911S production, and comparing VIN's to engine serial #'s the deficit appears to grow throughout production. The last known engines appear in the last chassis. This clearly suggests to me that there is a missing engine type.

BTW, the Factory literature also does not mention that there were two 5 speed manual transmission serial ranges. Type 911/01 low range was from 7110001 to 7119999 (which filled the available range), and then the high range started at 7710001 and so far is in the 800's. The dual range was also true in 1970. If you are lucky and find the type # as 911/01 11 plus serial then you have a case that originally had a limited slip differential installed. An LSD installed in a 4 speed box would be much more rare.

You can aid my research, and help the broader community, by sending me data on all 1971 911's (chassis, engines and transmissions). If you come across anything unusual, please get photos. Scans of CoA's are most helpful, as would actual paint codes from the badge, and the chassis production from the lower dash frame. I will keep all of the information confidential unless specifically stated. Please send all information to: kardex@bell.net

I hope that someone can come up with the clue that WE need to solve this problem.

[210bhp]

Hello Dave

Do you have a clear indication every chassis built was actually progressed to completion as a standard production vehicle for sale to the general public?

Was it not the case that some shells were factory replacements for damaged and crashed customer cars where mechanicals were still useable?
Were there not a few shells used for crash testing by the factory?

I think you will be unable to get much data on 1971 S models from this side of the pond as there were so few built, 40 coupes and of course no Rhd targa’s in any model although I do have 4 S, 4 E and 27 T targa’s registered in 1971 which must all have been Lhd. The pickings for E’ coupes will be pretty thin too as there were only 53 of those. 64 Porsche built and 9 Karmann built T’ coupes make a UK registered total of 205 cars for 1971. I don’t think this data is likely to plug many holes for you as very few of the Rhd cars out of that small production actually survive here. I believe the number of 1971 S’s surviving may well be in single figures.

I would suggest the answers you are seeking will probably come from German in particular, or other European delivered vehicles in general, as they were the bulk production markets in that year.

Regards
Mike

[davep]

Good thoughts Mike. The test chassis should have been in the first ten of each model type, and thus not production vehicles. Replacement bodies are a different set of numbers entirely. Neither of these should have anything to do with the 911S production bodies for coupe and Targa. The fact that for the T&E there are excess engines and a 11% deficit for the 911S strongly suggests to me that something is wrong. Your first question has me puzzled a bit. We would expect for the 911S coupe that a quantity would be diverted to race cars and have race engines installed. I just have difficulty accepting that about 240 would be converted to race cars.
I accept that the UK is not too likely to have many remaining cars. I do understand though that one or more people have access to the records of those that were imported, and thus may be in a position to assist. However, I want to leave no shed unchecked. Friends, such as Hugh in Australia, are helping me out with data. I have little access to the European market mostly due to language issues, but some members here probably have access to other forums.

[murph2309]

Hi Dave - I'm in the USA right now, but when I get back next weekend will dig out the details for my 911s targa, it's a sept '70 build, by MY 71, is that useful?

[davep]

Yes, that would be useful.
It appears that there is a big gap in the 911S coupe chassis #'s from mid 0800's to late 1000's. No idea why, but it helps to make sense of the lack of engines. So if anyone has a 911S coupe in that range, please contact me. So now I need to find out the production numbers stamped on the lower dash frame, hidden by the kneepad of all the late 1971 coupe bodies except Karmann; 911T near 9111102583, 911E near 9111201088 and 911S near 9111301430. If I can get the highest production coupe body # then I will know if the bodies are short as well.

[murph2309]

Dave - PM sent.

R

[davep]

Can anyone make a contribution to this research? I would like to make a statement on the results of my research very soon, and need more data.
Dave

[davep]

So I was minding my business when a member asked a question regarding a 1971 911S engine serial #. The number he was seeing was well above the normal range of serial #'s for the manual transmission engine type 911/02 6310001 to 6311959, but not in the range of the race engines types 911/2x. It turns out that some scratches changed the appearance of a digit, so it was a false alarm.

However, to my alarm I noticed that the reported serial range of the engine type only amounted to a total of 1959 engines, while the total 911S bodies was 2198. The Coupé range from 9111300011to 9111301430 and the Targa range from 9111310011 to 9111310788; so 1420 + 778 = 2198. Normally the quantity of engines exceeds the quantity of bodies by a small percentage, so a shortage of about 250 engines is serious. The highest serial race engine I know of is only 11; so the race engines are not likely to make up the shortfall. What about the Sportomatic? The literature of the time says that the 1970 and 1971 911S was not fitted with a Sportomatic; but perhaps a few custom made cars were made for special customers. There is also the missing type # 911/05 that would fit perfectly with a Sportomatic 911S engine. However, an exhaustive search turns up no evidence of a Sportomatic 911S for these two years.

Well, it turns out that having collected data over 50 years from many sources allows me to see that the highest engine serial #'s matches well with the highest chassis numbers. So both the chassis ranges and the engine range seem to be correct. There does seem to be an interesting anomoly though; I have 112 chassis #'s over the 911S Coupé range, so about 8% of the range. The biggest gap between two cars is 66 except for a whopping 252 car gap between 9111300842 and 9111301094. A significant amount of prodding of my sources for information resulted in the discovery that 236 chassis from 9111300852 to 9111301087 were not built. No explanation is known. I believe the time period is late March or early April 1971.
Further research is being done to find the production numbers from the cars before and after the gap; also needed are the production and chassis numbers of other Porsche built coupes with similar production numbers, and the production and chassis numbers of all Porsche built coupes near the end of the chassis ranges. Everyone with a 1971 Porsche built coupe is encouraged to send me chassis #, production #, engine and transmission #'s and whatever date information is available. Full CoA's are welcome.

[210bhp]

Interesting research Dave.
So a couple of questions just to clarify things in my mind,

You suspect the gap in the chassis production numbers sequence, ‘the missing cars’, match the missing engine numbers sequence , roughly speaking?
Do you suspect the missing sequence also appear in the E or T range of chassis and engine numbers or is it just the S model?

Thanks for sharing,

Regards
Mike

[davep]

Mike, it appears that the only gap that exists is in the 911S coupe VIN series. No engine # gaps that I am aware of, except for the known reserved series for the 1965 911 engine where the production engines started at 900101; lower #'s were used for prototypes. Also no other VIN gaps except for the previously known gaps at the end of the 1966 model year in the 911 and Porsche built 912. Also we know that there are unused VIN at the beginning of each series from 1970; so the 1971 911S production started at 9111300011 (the first ten are reserved). Later in the 1980's the first 60 were reserved except in special circumstances.
This gap in the middle of an assigned VIN range is very unusual and not previously known as far as I am aware.
With the missing cars, the remaining cars and engines match nicely. Always an excess of engines.

[210bhp]

So your assumption at this point is there must have been a halt in S coupe production for a week or two in March/April 1971 and resumption of production started with a vin number the factory thought they might have been up to if production had carried on as normal?

Regards
Mike

[davep]

Actually, I think something may have happened on the production line to either lose track of the series, or perhaps to get around damaged or missing VIN articles. The production order, Fahrzeug Auftrag, would have the production number on it and the build particulars attached. Then the labels with VIN, engine # and transmission # are attached to the production order as the engine & transmission are installed and the VIN is assigned, the number stamped, and the tags attached. So, I suspect that if the printed label with the VIN or the tags are missing, then the VIN would not be used. Exactly where in the production process the VIN was assigned and stamped into the chassis sheet metal I do not know. I just think that they were forced by circumstances to skip all those VIN's.