A HYPOTHETICAL.
PAINT STAMP ENGINE NUMBER.
this is a guess at this stage.
the statistical sample of data confirmed is too small for any degree of certainty.
we only have examples of 1 or 2 cars in each case.
# 604 was found on two cars.
both EC-B.
neither car was fitted with a gauge pack/console from new or ordered with the gauge pack/console. (the pack was more normally an option for 2.0 L cars and part of their appearance group option package). the history of one of these cars is well documented and it remains with the second owner.
# 605 was found on one car.
EC-B
the car was fitted with the gauge /console from new.
the history of the car is known from new. it remains with the original owner.
#606 was found on one car.
EC-A
this car was not fitted with gauge/console when sold new.
the car history is known from new and remains with the original purchaser family.
#607 was found on two cars.
EC-A
only one car had sufficient documentation to determine that it was special ordered from the factory with an "app group" option (gauge/console). the car was tourist delivered to the original owner at the karmann factory in germany.
there is one distinguishing feature of 1.8 engines when fully assembled that sets them apart from 2.0 L engines.
1.8 engines came with a standard type second sump lid without provision for a temp
guage sensor and electrical connection unless it was ordered.
Click to view attachment Click to view attachment Click to view attachment all 2.0 engines came with the different second sump lid with the inbuilt sensor and electrical connection.
Click to view attachment Click to view attachment it was a relatively simple matter to incorporate the gauge and console for the 2.0 either on the production line or at the dealer to suit customer preference.
it was more complex to incorporate gauges for the 1.8 as removal of the sump plate and opening of the sealed engine component with loss of oil was involved. esp so on the production line. (less so at the dealer).
if 1.8s were ordered with the exceptional and unusual option of guage and console this would have to have been allowed for on the production line.
this may have necessitated engine code stamps to ensure correct engine installation.
example of 74 1.8, no gauges/console. second sump lid plate is simple type.
Click to view attachment Click to view attachment Click to view attachment example of 74 2.0, without appearance group option of guages/console.
second sump lid plate is temp sensor type even though gauges not fitted.
Click to view attachment Click to view attachmentClick to view attachment this pattern appears to continue for the 1975 MY
example of 75 1.8, no gauges/console. second sump lid plate is simple type.
Click to view attachment Click to view attachment Click to view attachment example of 75 2.0, without appearance group option of gauges/console.
second sump lid plate is temp sensor type even though gauges not fitted.
Click to view attachment Click to view attachment Click to view attachmentthe above examples are vgc and appear to be original cars.
there are two possible ways to test the hypothesis of paint stamp engine numbers further.
1. collect more data on 74 1.8 engines to get a greater statistical sample.
2, expand data collection to 75 1.8 L cars.
if the hypothesis is correct there will be 4 stamped numbers for 75 1.8 cars.
a number for 49 state cars (no gauges).
a number for 49 state cars (gauges)
a number for calif cars (no gauges)
a number for calif cars (gauges)
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further, if members with 73 cars were interested.
the guage/console option was on offer in 73.
a possibility is -
for EA engines.
a number for no guage cars.
a number for cars fitted with guages (from new from factory).
for EB engines
a number for no guage cars.
a number for cars fitted with guages (from new from factory).
= 4 numbers in total.
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for 2.0 L cars for 75/76 model years.
it looks to me like the only difference in the cars is whether 49 states or californian.
if the hypothesis is correct (and the only difference between 75/76 2.0 L engines is pollution equipment/specification) there will be two numbers for engine paint stamps for each of the the years.
one for 49 states.
one for california.
73/74 2.0 L cars will have one number for 49 states and california, no difference in emissions spec for those two years?
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the exceptions to the above will be engines stamped with EA370 or possibly some other identifying stamp. those stamps appear to identify those engines with the early stage of an engine program connected with cars 73 and beyond. ie the discontinuation of the porsche 6 cylinder engine and the revamping of the engine range towards the 2.0 L and 1.8 L cars. EA370 is the project development # covering that program?
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EDIT MAY 2022
further information that has come to light.
for a standard 74 1.8 to be fitted with a console and temp gauge option, in addition to the temp sensor sump lid plate the fully assembled engine would require 3 metal brackets with a crimped end to locate and support the temp sensor wiring clear of the crankcase and oil cooler. these are shown listed 1, 2 & 3 in images below.
1 was incorporated into the original factory sump lid temp sensor housing.
2 was fixed using one of the oil filter housing bolts.
3 was fixed using one of the oil cooler support bracket bolts.
all were not easy to access/fit with the cast fan housing on the assembled engine.
only 914/2.0L engines came with the sump lid plate, temp sensor wire supports and temp sensor wire in place on the assembled engine.
all 914/2.0 L cars were fitted with a temp gauge, either a standard temp gauge in the left hand combo gauge in the instrument binnacle or optioned with the centre console and gauge pack. all 2.0 L engines came with the necessary lid, temp sensor wire and support brackets already fitted.
standard 914/1.8s were not fitted with a temp gauge as standard, but were fitted with a standard wiring loom with provision for a temp gauge. they lacked the temp sensor sump lid, temp sensor wire and support brackets on the assembled engine to make fitting the console a simple plug and play into the wiring loom in the upper engine bay.
914/1.8s could be special ordered with the centre console and gauge pack.
this would have required that the engine was assembled at the VW engine plant with the temp lid, temp sensor wire and brackets in place.
it seems highly likely that the pattern found in existing original cars of:
604 = EC-B engine/car without gauge console.
605 = EC-B engine/car with gauge console.
606 = EC-A engine/car without gauge console.
607 = EC-A engine/car with gauge console.
is the reason for the two different paint stamp engine tin numbers for each of the EC-A or EC-B variants.
608 has been established as the paint stamp number for the 74 AN european spec 1.8 twin carb engine. the car with the 608 engine was not fitted with gauge console.
it is highly likely that a 609 engine existed and this would have been the AN engine fitted to european 1.8s with the gauge console option.
Click to view attachment Click to view attachment Click to view attachmentengine tin paint stamp.
1974 1.8 / european spec AN.
held in the collection of the porsche museum germany.
engine stamp # = 608
Click to view attachment
bubbling up there with no ECU to hide it.
