Early production volume calculations - 1977-78
#1
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Early production volume calculations - 1977-78
How many RoW MY78 928's were built before US production started?
AND
How many 928's were build on average per day?
___________________________________________________
Here's what I know:
Official production of '78 MY 928 began in May 1977 for RoW cars, and August 1977 for US (& RoW).
-Projekt 928, Brian Long & Erkka Vilhuer
US VIN 928200016 build sticker reads 08/77
US VIN 928200029 build sticker reads 08/77
___________________________________________________
Production:
..."Production eventually got under way ... in May 1977. Schedules initially called for a rate of 5 cars a day, rising to 15 in the summer."
-Brian Long
___________________________________________________
The Numbers:
Per Master VIN thread:
3785 total RoW & US
Note: Japan number (75) excluded for simplicity
___________________________________________________
Important regarding VINs:
US and RoW VINs ran in parallel, meaning there are two parallel serial numbers of each. (parallel serial numbers = oxymoron? )
The difference is in the VIN - 9288100016 RoW & 9288200016 US (difference is the '1' vs. '2' modifier)
This is 9288100016
This is 9288200016
Definitely siblings, but built months apart.
___________________________________________________
The Key:
MY78 is interesting because it consists of a total of 15 months (65 weeks) of actual production. This is how:
The remainder of 1977 from May - 8 months (35 weeks)
PLUS
1978 thru July - 7 months (30 weeks)
Note: It's my understanding that Erkka's numbers reflect this 15 month span, were a production changeover occurred in August 1978.
___________________________________________________
The Math:
2646 RoW cars produced over 15 months works out to 176 cars/month
Which means:
529 RoW cars were produced thru July 1977, prior to US production startup.
13 weeks (65 working days) works out to 8 cars/day average.
This sounds about right to me, considering early production ramp-up
-------------------------------------------------------------
1139 US cars produced over 12 months (May/77 thru July/77 removed) works out to 95 cars/month
PLUS
176 cars/month RoW = 271 cars/month, both US & RoW
@ 12 months = 3251 cars total
52 weeks (260 working days) works out to 13 cars/day average.
This sounds right, considering Brian Long mentioned a 15/day production schedule.
-------------------------------------------------------------
Quick backmath works out closely:
529 RoW + 3251 RoW & US = 3780 total RoW & US MY78.
Compare to Erkka's number of 3785
-------------------------------------------------------------
Erik's US 1978 #0941 built 05/78 reflects a later May build.
941 plus 95 cars in June plus 95 cars in July equals 1131 total, finished by August production changeover.
Erkka's total US = 1139
Pretty darn close!
___________________________________________________
In Summary:
An estimated 529 Euro/RoW 928's were build between May and July 1977, before the first US destination 928 was built.
Production volume averaged 8 928's per day starting out, then ramped-up to 13 per day.
Keep in mind this is an estimate, and my approach as rather linear.
See, there may have been a higher proportion of RoW earlier, then tapered off as US production ramped-up.
___________________________________________________
So, if you made it thru my "chicken scratch" .... any thoughts?
Thanks!
AND
How many 928's were build on average per day?
___________________________________________________
Here's what I know:
Official production of '78 MY 928 began in May 1977 for RoW cars, and August 1977 for US (& RoW).
-Projekt 928, Brian Long & Erkka Vilhuer
US VIN 928200016 build sticker reads 08/77
US VIN 928200029 build sticker reads 08/77
___________________________________________________
Production:
..."Production eventually got under way ... in May 1977. Schedules initially called for a rate of 5 cars a day, rising to 15 in the summer."
-Brian Long
___________________________________________________
The Numbers:
Per Master VIN thread:
Code:
MY Model Market Smallest VIN Largest VIN Qty Total --------------------------------------------------------------- 78 928 ROW 9288100001 - 102646 2646 928 USA+CAN 9288200001 - 201139 1139 928 Japan 9288209501 - 209575 75 3860 Excerpt from Post #1, by Erkka Vilhuer
Note: Japan number (75) excluded for simplicity
___________________________________________________
Important regarding VINs:
US and RoW VINs ran in parallel, meaning there are two parallel serial numbers of each. (parallel serial numbers = oxymoron? )
The difference is in the VIN - 9288100016 RoW & 9288200016 US (difference is the '1' vs. '2' modifier)
This is 9288100016
This is 9288200016
Definitely siblings, but built months apart.
___________________________________________________
The Key:
MY78 is interesting because it consists of a total of 15 months (65 weeks) of actual production. This is how:
The remainder of 1977 from May - 8 months (35 weeks)
PLUS
1978 thru July - 7 months (30 weeks)
Note: It's my understanding that Erkka's numbers reflect this 15 month span, were a production changeover occurred in August 1978.
___________________________________________________
The Math:
2646 RoW cars produced over 15 months works out to 176 cars/month
Which means:
529 RoW cars were produced thru July 1977, prior to US production startup.
13 weeks (65 working days) works out to 8 cars/day average.
This sounds about right to me, considering early production ramp-up
-------------------------------------------------------------
1139 US cars produced over 12 months (May/77 thru July/77 removed) works out to 95 cars/month
PLUS
176 cars/month RoW = 271 cars/month, both US & RoW
@ 12 months = 3251 cars total
52 weeks (260 working days) works out to 13 cars/day average.
This sounds right, considering Brian Long mentioned a 15/day production schedule.
-------------------------------------------------------------
Quick backmath works out closely:
529 RoW + 3251 RoW & US = 3780 total RoW & US MY78.
Compare to Erkka's number of 3785
-------------------------------------------------------------
Erik's US 1978 #0941 built 05/78 reflects a later May build.
941 plus 95 cars in June plus 95 cars in July equals 1131 total, finished by August production changeover.
Erkka's total US = 1139
Pretty darn close!
___________________________________________________
In Summary:
An estimated 529 Euro/RoW 928's were build between May and July 1977, before the first US destination 928 was built.
Production volume averaged 8 928's per day starting out, then ramped-up to 13 per day.
Keep in mind this is an estimate, and my approach as rather linear.
See, there may have been a higher proportion of RoW earlier, then tapered off as US production ramped-up.
___________________________________________________
So, if you made it thru my "chicken scratch" .... any thoughts?
Thanks!
Last edited by Jadz928; 02-08-2012 at 08:39 PM. Reason: revised math to reflect Aug MY production changeover
#3
Rennlist Member
Thread Starter
Great question!
My guess is no. Not sure when the break occured, and if the break was "sharp or feathered in". May?
In my notes, I have listed April as Porsche MY changeover. Could someone substantiate this?
EDIT: Erkka suggests August for production changeover
Yes. My undertstanding is Erkka seperated '79 volumes from calender year '78. Brian Long and Jorg Austen used calendar year volumes, which skewed MY78.
Using his MY79 volumes and a 12 month production run, they averaged 20 cars/day. '79 was this biggest production volume year for the entire marque.
My guess is no. Not sure when the break occured, and if the break was "sharp or feathered in". May?
In my notes, I have listed April as Porsche MY changeover. Could someone substantiate this?
EDIT: Erkka suggests August for production changeover
Yes. My undertstanding is Erkka seperated '79 volumes from calender year '78. Brian Long and Jorg Austen used calendar year volumes, which skewed MY78.
Using his MY79 volumes and a 12 month production run, they averaged 20 cars/day. '79 was this biggest production volume year for the entire marque.
Last edited by Jadz928; 08-24-2011 at 09:43 PM.
#5
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Thread Starter
I believe this sampling has already occurred. I'm hoping a couple of folks much wiser than myself will chime in....
#7
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Thread Starter
However, a high US VIN/build date sticker would be interesting to see!
Anything over 1000, MY78.
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#9
Been selling Twinkies on Ebay,
have some extra cash right now.
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have some extra cash right now.
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1978 #0941 built 05/78
EDIT: VIN sticker is the same as in post #6 (ends in 02, silver color) but it DOES have the build date. Interesting that #0016 has a sticker P/N ending in 03, while later cars end in 02...
EDIT: VIN sticker is the same as in post #6 (ends in 02, silver color) but it DOES have the build date. Interesting that #0016 has a sticker P/N ending in 03, while later cars end in 02...
Last edited by Erik N; 08-25-2011 at 02:55 PM.
#10
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#11
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Here`s a puzzle Jim - the two VIN pics you posted (016 and 029) have black VIN stickers with part no. 928 701 112 03. The silver VIN sticker I posted (0174), with no date, has an earlier part no. 928 701 112 02. I wonder if 928Shane`s without date code is the earlier silver label...
#14
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AFAIK '79 MY production started in 08/78. Model year did almost always change in late summer of previous calendar year. Only exceptions were M718 option US GTS.
Austen book tries to give true model year info but it has many mistakes. Long book and few other sources have calendar year info which is really not useful in determing how many cars were made each model year.
PET information for part changes can be possibly used to give timeline what cars were on production line at same time. For example clutch center shaft and torque tube changed in middle of '78 MY some time in fall of 1977.
92881 00753
92882 00054
92882 09522
Above were last VIN's to use early style setup. If change was done at same time for all markets it can give pretty good idea how many ROW cars were made at the time. Some other part changes have clearly been done at different times for different markets. For example fuel pump and hose related changes do no make sense if they were done at same time.
Austen book tries to give true model year info but it has many mistakes. Long book and few other sources have calendar year info which is really not useful in determing how many cars were made each model year.
PET information for part changes can be possibly used to give timeline what cars were on production line at same time. For example clutch center shaft and torque tube changed in middle of '78 MY some time in fall of 1977.
92881 00753
92882 00054
92882 09522
Above were last VIN's to use early style setup. If change was done at same time for all markets it can give pretty good idea how many ROW cars were made at the time. Some other part changes have clearly been done at different times for different markets. For example fuel pump and hose related changes do no make sense if they were done at same time.
#15
Rennlist Member
Ahh, so anybody who has access to early documentation & WSB can collect potentially relevant data.....
Some triangulation references from a quick scan of the TSB's.....
NOTE: car 8200054 is mentioned in at least 6 TSB's, meaning it was the beginning car for a series of changes.
This would be best-displayed in a timeline format, perhaps we can do that as we collect more info.
Some triangulation references from a quick scan of the TSB's.....
NOTE: car 8200054 is mentioned in at least 6 TSB's, meaning it was the beginning car for a series of changes.
This would be best-displayed in a timeline format, perhaps we can do that as we collect more info.