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914World.com _ 914World Garage _ Early versus late 1974
Posted by: Lockwodo Jan 19 2022, 07:47 PM
Would anyone happen to know what the breakpoint in VIN #s is for "early" 1974 versus "late" 1974 914s?
Posted by: sixnotfour Jan 19 2022, 07:49 PM
there is early and late 73's
Posted by: billh1963 Jan 19 2022, 07:57 PM
there is early and late 73's
That's what I remember...one of the biggest changes being the addition of the reinforcing bar in the doors of the late '73's.
Posted by: Van B Jan 19 2022, 08:12 PM
What are you looking for; engine or chassis differences?
@http://www.914world.com/bbs2/index.php?showuser=24231 has done a fair bit of work mapping out the changes for the 1.8L
Posted by: JeffBowlsby Jan 19 2022, 08:44 PM
I have owned both 'early and late' '74 2.0Ls.
Do not know of a definitive list of changes, nor the VIN inflection point which seems to be a progressive set of dates depending on the change, not a single date. The factory parts manual may indicate changes to spcific parts associated with a VIN.
Some differences:
-silver center gauges changed to black center gauges
-charcoal canister relocated from fuel tank to engine bay rear wall
-carpeting changed from solid colors to 'salt and pepper' patterns
-a brief period of a few weeks in Spring of 74 when grey headlight relay covers were installed
-fuel expansion chamber and fuel tank cap changed from metal to plastic
Interestingly, the Can Am cars produced in the Spring of 74 include a range of these changes.
Thats all I can think of right now.
Posted by: Lockwodo Jan 19 2022, 08:59 PM
Well, what started me wondering is that in the 914/4 Tech Notebook there are two vacuum hose diagrams applicable to the '74 2.0, attributed to Jeff Bowlsby. One is for "1973 thru early 1974" and the other is for "late 1974". Sounds like there isn't a VIN cutoff point, so I'll just compare both diagrams to what I've got and see which matches. It's probably the late 1974 diagram since I have the black center gauges and charcoal canister in the engine compartment.
Posted by: wonkipop Jan 19 2022, 10:02 PM
@http://www.914world.com/bbs2/index.php?showuser=26193
this might answer some of your questions.
http://www.914world.com/bbs2/index.php?showtopic=357407
some of us 1.8 owners put our heads together last year.
the idea of early and late 74s might be a bit of a myth.
least when it comes to 1.8s and vac hoses and cans specifically.
charcoal can gets changed very early in the 74 production run (nov 73) - about a months worth of 1.8s had cans in the frunk.
2 different vac hose layouts to the throttle body are simultaneous.
one layout for california, one for the 49 states.
all in the thread linked above.
jeff bowlsby and others know all about the 2.0s.
and some of those other detail changes, gauges etc.
thanks to jeff's prompt we embarked on clarifying the 1,8s engine hose layouts.
Posted by: JeffBowlsby Jan 19 2022, 10:21 PM
…we embarked on clarifying the 1,8s engine hose layouts.
And you did an excellent job with that research, thank you.
Posted by: Dave_Darling Jan 19 2022, 11:13 PM
I think that the only difference in terms of hoses is that the earlier 74s have the charcoal canister up front, like the 70-73 cars do, while the later 74s have it in the engine bay like the 75+ cars do.
My 10/73 build 2.0 has the front-mounted canister. My old 1.8, which I think was also built around 10/73 according to the door jamb tag, had the canister in the engine bay.
--DD
Posted by: wonkipop Jan 20 2022, 03:36 AM
I think that the only difference in terms of hoses is that the earlier 74s have the charcoal canister up front, like the 70-73 cars do, while the later 74s have it in the engine bay like the 75+ cars do.
My 10/73 build 2.0 has the front-mounted canister. My old 1.8, which I think was also built around 10/73 according to the door jamb tag, had the canister in the engine bay.
--DD
we finished off what you started more than 10 years ago dave.
between you and jeff - what you guys had down on the record together, the old how many hoses from distributor to throttle body - and why - was crackable.
bit of head scratching and 50 years after it all went down in western germany, i think we got to the bottom of it,.
i read a few of your comments on other sites and here from a decade ago and i commend your open minded-ness and reporting on what you saw on the objects themselves.
Posted by: Lockwodo Jan 20 2022, 08:35 AM
Thanks guys, this is all super helpful! I'm new to 914s and air cooled VW engines and appreciate the wealth of info and helpful pointers from this community.
Posted by: wonkipop Jan 20 2022, 12:57 PM
-a brief period of a few weeks in Spring of 74 when grey headlight relay covers were installed
.
interesting. mine is jan/74 1.8. grey headlight relay covers.
that would be a winter build?
Posted by: dr914@autoatlanta.com Jan 20 2022, 01:03 PM
there was a gradual transition but usually started in january 74
Would anyone happen to know what the breakpoint in VIN #s is for "early" 1974 versus "late" 1974 914s?
Posted by: dr914@autoatlanta.com Jan 20 2022, 01:05 PM
the 914 restorers guide by brett johnson is quite good on showing the differences between early 74 and late 74
Would anyone happen to know what the breakpoint in VIN #s is for "early" 1974 versus "late" 1974 914s?
Posted by: lesorubcheek Jan 20 2022, 04:58 PM
One change that is referenced in the PET for 1974 was the brake pressure regulator. The PET calls out VIN 4742915751 as the changeover point. No idea if the other changes listed have any correlation with this VIN.
Dan
Posted by: wonkipop Jan 20 2022, 08:09 PM
One change that is referenced in the PET for 1974 was the brake pressure regulator. The PET calls out VIN 4742915751 as the changeover point. No idea if the other changes listed have any correlation with this VIN.
Dan
no. its not to do with that vin.
and much as i respect dr914, its not a start of jan 74 thing either.
at least for some of the changes.
the charcoal can shift (for 1,8s) is between vin 09104 and 09760 - which dates at between 20 and 28 Nov 73.
the 2 different 1.8 hose set ups for dist advance and retard has nothing to do with a changeover at a date. california cars from the start are no advance hook up, 49 state cars are advance and retard hook up. that was established beyond a doubt.
the documents which clarify which are which are houseed in the CARB (california air resources board) archive. one of our members here L-JET914 found the documents.
production of 1.8s does not commence until very late october 73.
i'm not sure whether that was well known. i'm guessing knowledgable folks here already knew that. from august to late october 73 the factory produced 2.0 L cars exclusively it would seem. possibly euro spec 1.8s were produced before late oct 73.
as to other changes.
some folks have the dates for things like petrol tank change to plastic.
silver versus black dials.
i think mr. b (jeff) has a handle on quite a bit of it all. i would agree with his view that its more random and the changes don't all happen at once at or around one date.
all we 1.8 owners found to add to the information was.
1) a narrowing down of the window on the charcoal can to a week in november. (this date may have already been pinpointed by dr. johnson - i don't have his latest edition of restorer's guide to see what he said). that change seems to occur just after the factory commenced production of 1.8s in oct 73.
2) documentation that confirmed there were two types of EC engines.
An A and a B. simultaneously produced. one for calif. one for rest of USA.
this cleared up the mystery and debate around hoses that occurred a decade ago.
additionally members had access to information that said where cars had been originally sold new. this confirmed that there was one vac hose set up for cal cars and the other for USA.
what we found is all in that thread i linked.
Posted by: davep Jan 21 2022, 09:18 AM
There is also the matter of the location of the Karmann body # which moved from the rear trunk floor to a tag in the front trunk. The change was probably in April with a VIN in the 16000 range. See this thread:
http://www.914world.com/bbs2/index.php?showtopic=76497
Posted by: Mark Henry Jan 21 2022, 09:39 AM
It also depends on what was in the parts bin that day, VW was famous for using up what's on hand.
My 914 is a November '73 build, no silver dots.
Posted by: StarBear Jan 21 2022, 10:16 AM
…we embarked on clarifying the 1,8s engine hose layouts.
And you did an excellent job with that research, thank you.
Posted by: wonkipop Jan 21 2022, 08:10 PM
It also depends on what was in the parts bin that day, VW was famous for using up what's on hand.
My 914 is a November '73 build, no silver dots.
@http://www.914world.com/bbs2/index.php?showuser=697 Henry
mark, was your car a 1.8 or 2.0 new?
Posted by: Lockwodo Jan 22 2022, 08:09 AM
I have owned both 'early and late' '74 2.0Ls.
Do not know of a definitive list of changes, nor the VIN inflection point which seems to be a progressive set of dates depending on the change, not a single date. The factory parts manual may indicate changes to spcific parts associated with a VIN.
Some differences:
-silver center gauges changed to black center gauges
-charcoal canister relocated from fuel tank to engine bay rear wall
-carpeting changed from solid colors to 'salt and pepper' patterns
-a brief period of a few weeks in Spring of 74 when grey headlight relay covers were installed
-fuel expansion chamber and fuel tank cap changed from metal to plastic
Interestingly, the Can Am cars produced in the Spring of 74 include a range of these changes.
Thats all I can think of right now.
As I compared the "early" and "late" vacuum diagrams to my '74 2.0, I noticed that the throttle body on my car only has one vacuum port, and it looks like this port is intended to be connected to the retard vacuum port on the distributor advance can (but the previous owner left it disconnected). The advance vacuum port on the distributor advance can is just sitting there open with nothing to connect to. So my questions are 1) does the distributor vacuum advance can port not need to be connected to a source of vacuum?, 2) should the existing hose from the throttle body vacuum port be connected to the distributor retard can port, or does it matter?, 3) should I find a throttle body with two vacuum ports and connect both to the distributor advance can? As it sits, the car seems to run and accelerate fine without vacuum to the distributor advance or retard. Thanks, Doug
Posted by: wonkipop Jan 22 2022, 03:24 PM
@http://www.914world.com/bbs2/index.php?showuser=26193 ,
the 2.0L guys will have to answer the question you have about retard being hooked up.
........but if 2.0s are anything like 1.8s the retard port is for emissions at idle.
doesn't mean to say they are the same, as 2.0s are D jet.
theoretically it should run better at idle without the retard hooked up.
i think.
-------
@http://www.914world.com/bbs2/index.php?showuser=104 .
i downloaded all the CARB documents when i was in the archive getting the 1.8 stuff.
maybe this is of interest to you.
i went back and had a look at them in my files after @http://www.914world.com/bbs2/index.php?showuser=26193 posted his questions.
Oct 72 CARB documents (covering 1.7s and 2.0s) for 73 model year.
both have vacuum advance and retard activated for distributor/throttle body.
Oct 73 CARB documents (covering 2.0s) for 74 model year.
now only has retard activated for dist/tb.
i'll leave 2.0 experts to work this out.
1.8 stuff gave me enough of a headache.
........it seems to say.
at minimum what is called a late 74 2.0 (hose layout only vac retard) was a california car? just like the 1.8s.
or.
74 2.0 L was a universal car (50 states) and had only retard.
or 74 did change at some stage during model year to conform to CARB.
and was a 50 states car when it did that change as well. ie they just applied CARB requirements across the board.
?????????
Posted by: JeffBowlsby Jan 24 2022, 07:41 AM
As I compared the "early" and "late" vacuum diagrams to my '74 2.0, I noticed that the throttle body on my car only has one vacuum port, and it looks like this port is intended to be connected to the retard vacuum port on the distributor advance can (but the previous owner left it disconnected). The advance vacuum port on the distributor advance can is just sitting there open with nothing to connect to. So my questions are 1) does the distributor vacuum advance can port not need to be connected to a source of vacuum?, 2) should the existing hose from the throttle body vacuum port be connected to the distributor retard can port, or does it matter?, 3) should I find a throttle body with two vacuum ports and connect both to the distributor advance can? As it sits, the car seems to run and accelerate fine without vacuum to the distributor advance or retard. Thanks, Doug
73 2.0L two throttle body ports, connect to vacuum can both vacuum can ports to the throttle body per Dave Darlings diagram.
74 2.0L only one throttle body port, connect to vacuum can retard port only per my diagram. The advance port hose is short (~6 in or so) and is not connected, orients under the air plenum. Advance is not functional but thats the way its been documented on numerous cars as from the factory. It was an emissions 'feature'.
Posted by: Mark Henry Jan 24 2022, 08:01 AM
It also depends on what was in the parts bin that day, VW was famous for using up what's on hand.
My 914 is a November '73 build, no silver dots.
@http://www.914world.com/bbs2/index.php?showuser=697 Henry
mark, was your car a 1.8 or 2.0 new?
1.8
Posted by: Eric_Shea Jan 24 2022, 08:23 AM
As Dan mentioned, pressure regulator changed slightly which means almost all of the rear lines are different (through firewall and left and right).
Posted by: wonkipop Jan 24 2022, 02:21 PM
It also depends on what was in the parts bin that day, VW was famous for using up what's on hand.
My 914 is a November '73 build, no silver dots.
@http://www.914world.com/bbs2/index.php?showuser=697 Henry
mark, was your car a 1.8 or 2.0 new?
1.8
front trunk or engine bay can?
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