alright @JeffBowlsby

i dug into heat protected glass this afternoon.
its not tint - here is the distinction.
@vitamin914 will correct me if i am way wrong.

tints work by cutting down in the visible spectrum of light.
this was incompatible with transparency standards at that time. 70%.
the glass itself was almost at the 70% all on its own before you even thought of tinting = no tinting. often even on side glass. at least not legally back then.

so they came up with heat absorbing glass.
which deals with light in the infrared spectrum but does not affect visible wavelengths.
so they could do heat control and still pass visibility/transparency regulation.

the modern form of one of these treatments or types of glass more properly is IRR
infra-red reflectance glass. it works just as the name suggests. reflects the heat spectrum and glass does not absorb it. its proper abbreviation is IRR.
sound familiar?

the earlier form was infra-red absorbent glass. IRA. not the irish republican army the nuns used to collect for. it didn't really work. it absorbs the infra-red before it hits the interior but it ends up heating the glass itself which then radiants into the interior.
they really don't use this one any more. but it was the tech back in the day with 914s and other 70s cars.

its pretty obvious which screens are the heat protected screens - they are the ones that have IRA in the description line after the makers name.

so i am going to have to go back to my original position which is i don't agree with you that F means tint. there was no tint glass in 914s from factory. only heat control.

i know that upsets the reasoning on the side glass, but there has to be some other meaning to the 1 or F or 1F code there.

also thanks to @vitamin914 's superb breakdown on glass for idiots like me, i can now understand what is going on with early cars referring to plate and later ones referring to F or as i believe F to mean Float glass.

to begin with in early cars they were making the primary sheets of glass for the build up of the windscreens from plate glass. or as it was sometimes known. sheet glass. and as vitamin points out, older process, caused ripples in glass, had to be polished and ground flat to remove distortions in the case of windscreens, or even high end architectural use.
float let them produce flat sheets of glass more effeciently with either no polishing or very minimal polishing. cheaper in the long run.

so i think what we see with 914 windscreens is the flip over down at the kinonglas factory where they go from using plate or sheet glass as the raw base material to float glass.
and that happens around about 73 or so. maybe 74. the earlier ones are using S.
the later ones have the same descriptions for glass but use F. its basically essentially the same material just made a different way. of course it would have involved a whole new raft of tests and certificates because thats how bureacracy works. and maybe it had slightly different impact performance outcomes. who knows. you would have to see those codes to pick up any subtleties.

so at this stage i am saying the F/F is the clear screen. or it might be S/S or even just described as plate glass in earlier versions.

but if its got IRA in it, then its the heat control glass. and that can either have F or S in it depending on whether its pre 73/74 or after.

will need to find a better explanation for the side glass i think.
you might be correct about it in relation to side glass and heat control but it does not mean the logic extends to the windscreen so abruptly or directly. like F is all there is to it.

i could expand further. maybe they got performance out of vertical side glass that was F equal to performance out of IRA simply as a result of side glass being vertical and windscreen glass laying over on an angle and being laminated. ie this gave equal performance all round for the so called heat performing glass. given orientation of surfaces and sun assumed to be overhead.

and when you used the straight up F/F windscreen it gave the same performance as the clear or 1 grade glass on the side windows. my solar orientation on architectural windows is kicking in here.

back windows just got 1 grade DELOCURE because its passively shaded by the roll bar anyway. all they want there is heated glass for condensation control as a lux feature.

end of research.
been another roaster of a day here that denied me my 914 drive.

@JeffBowlsby
here is the example that perhaps clearly illustrates what i am talking about.

this car on BAT.
1974 1.8. claimed to be low mileage original. certainly very original.
the glass package is interesting.
its all photographed in the detail images.
its got an FIRA/F screen. its described as laminated F.
its side windows are DELODUR F
its order form/window sticker is marked as tinted glass option - all around.
unfortunately no image of rear window.
but its a pretty reliable example to go off in my humble opinion.

https://bringatrailer.com/listing/1974-porsche-914-59/


my car is a 74 1.8
it has an F/F screen. described as laminated F
DELODUR 1 side windows.
DELODUR 1 rear window.
i don't have an order form sadly. original owner never passed that on in the file.
the side windows sure are clear.
(why would you get tinted windows in maryland anyway? which is where it came from new).

i rest my case tentatively on these two examples for now.
FIRA/F + DELODUR F = so called "tinted glass" option. american terminology.
F/F + DELODUR 1 = standard clear glass package. no "tinted glass".

of course this is only good for 1974.

i know there is another 74 "tinted window" example somewhere in ECA/B files that is a car i came across. just have to find it again. and i know it had an order form.
a pretty good one actually as it was a tourist delivery USA car that was picked up from karmann factory. but would need to find it and look to see if it has glass images.
and there is always the question does it still have original screen.

Heat absorbing glass has been around for an awfully long time. PPG came out with Solex (now called Solexia by the new owners) back in the 1930s. Nothing really exotic about it, the glass has a greenish tinge or tint. It basically adds an impurity of iron and or chromium ions that does not transmit IR but absorbs it. I think it also has higher UV absorption too. The car still gets hot inside.

PPG had IR reflective glass (Sungate?) but I think this was a metallic coating on the inside next to the vinyl to reflect IR. They used to apply it with sputter coating ion deposition technology. From the late 80s onwards there was a big push to add technology to laminated parts. Thin film deposition gave better IR /UV performance (but would stop your radar detector from working too). Rain sensors, heated w/s, heads up display reflectors and all kinds of stuff. Most of it was gimmicky and short lived. About the only thing I sometimes see these days is a heating grid under the parked wipers for freezing rain. But I doubt these are useful in places like Los Angeles or Sydney.

One of my 914's replaced w/s is made with Solex glasss so it has been around for ages and continues to be made (the other w/s is made by Sigla so not OEM either). I'm sure other companies have identical equivalents - patents have long run out.

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I noticed something interesting when I was in a junk yard looking at dead 914s. All the cars that had heated rear windows had clear (not the greenish heat absorbing tint) glass all around. I guess it sort of makes sense - you don't need heat protection glass if the car is in a cold climate with a heated back window... I harvested a heated back window from one of the five dead 914s.

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Speaking of heated back windows... Tin float glass picks up tin ions in the surface that contacts the molten tin bath. With a UV light source, you can identify the tin side. It fluoresces a whitish glow compared to the non tin side. This is important for making windows with heated circuits. If the heated circuit is printed on the tin side it will appear a dark reddish brown color from the outside of the vehicle. If printed on the non tin side it would be a lighter orange color. Most auto companies wanted it darker although there were a few Japanese makers that wanted the lighter color ...more trivia.

@JeffBowlsby

now i know what i am looking for, found these easily trawling through BAT.
restricted search to 74 and above for the moment.
these examples show the combo of glass you got if you ticked tinted glass all round option.

2 full examples from 74 with showroom sticker/order form - or cert of authenticity.
tinted windows all round box ticked for both.
both have the FIRA/F screen, DELODUR F side windows.
one has an image of DELODUR 1 rear window.

1 example from 75. no cert of auth or showroom sticker.
but full package of window images.
as per both 74 except all glass has audi rings added to VW logo.

1 example from 1976 has showroom sticker/order form.
tinted windows all round box ticked.
as per 75. except side windows are DELODUR 1F.

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example of 74


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so far unsuccessful finding example like mine with an attached cert of auth/showroom order form. but have collected examples of other 74s matching mine.
F/F front screen with DELODUR 1 side glass in combo.
sure to pop up one eventually.
not every seller bothers to shoot the glass markings on BAT.

--------

found a bumblebee with a cert of authenticity that stated tinted windscreen.
as distinct from other four examples which stated tinted glass all round.
the example had its original windscreen replaced.
but all side glass looked original and aged.
all side glass was DELODUR 1.

--------

i'll keep the stuff i find filed.

the place for this thread or a new one that compiles the info clearly is probably better in the originality section of the website. but not just yet. we need some stuff from pre 74.
its not worth putting in until its been cracked with reasonable certainty.
--------

bonus find - 914/6 with a sudglas screen.
looks interesting.
black screen marking not white.
my guess - later OEM spare part from porsche.
sudglass must have run a batch but not during 914 production?
black markings on screen much more like modern windscreens similar black marks,
the screen has full set of standards printed on it.
French , German, USA, etc
its a infra-red screen.
of interest the interlayer in the screen looked like it was failing at all its corners.
quality control?

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excellent bit of info @vitamin914 .

i'd say thats pretty much all a 914 "tinted" screen is.

the DELODUR 1 on the side windows looks like its what we call low iron or ultra clear glass in construction circles. DELODUR 1 is probably toughened plate or sheet versus DELODUR F being toughened float. the glass would have come out of two different processes or production lines. the float glass they were using appears to have been naturally greener (darker) due to its composition.
they just amped it up with the outer layer of the windscreen lamination for the so called tinted screen with extra ingredients in the glass mix as you say.

i'll be interested to see if porsche museum gets back to me.
the curator did last time i wrote.
so long as you are very specific about what you want and it won't take too much time he wanders over with his iphone, takes a snap and emails it directly.

@wonkipop

I hope the curator sends something useful too. You would expect, if it is a good example, the car would be a rather unmolested original "production" vehicle. Of course there is always the danger that the glass was experimental i.e. not intended for public use. We had a research group that made all sorts of one-offs and specials. They even made huge bubble canopies with chemically tempered glass (like smartphone screens) for concept cars to show off capabilities.

@wonkipop
@jeffbowlsby

Ok, here’s mine. Yet again, different. 1974 1.8 with Apperance Group. Chassis from nov 73; build date May 74.
The windshield emblem in lower right by vin plate but very faint so not able to photograph. Has:
Flag-like Logo
Made In Western Germany
SIGLA
Squiggle wave D-79
DOT 25 M91
Yet the door glass and corner triangle glass look just like the others:
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Do, why would/should windshield be different? Original owner, so not replaced to my knowledge.

i was waiting for you to chime in @StarBear .

and upset the applecart.
thats very interesting about the sigla screen.

dunno.
maybe there is a variety of screens that went in at the factory after all.

be interesting to hear what @L-Jet914 has in his car as i believe it might be pretty original too. though windscreens are always hard ones as many got replaced.
but for sure you would know the history of yours.
about the only thing that could happen might be screen damaged during shipping out from germany back in time and screen replaced before delivery.
but thats just a guess. either variety of screens at factory depending on time of build or replacement. who knows?

PS - @StarBear judging from the side glass it looks like your car is "untinted" window package.
have you got a window sticker or order form still in your documentation that says how the car came regarding options?

its a good condition base model euro spec 74 1.8 the factory has. standard off production line.
it belonged to Horst Marchart the former development chief at Porsche - he worked on the development of the boxster. the car was his company car or personal car when he first worked at porsche as a young engineer. he donated it to the collection.
its hard to know to what degree it might have been "restored" or freshened up for the museum - but certainly the engine was in completely unmolested state.
ironically besides the two monster 914/8s they had it was for many years the only other 914 in the collection. these days they have a 6 as well but i believe it was bought from a 914/6 owner in the USA who had restored it beautifully. they didn't seem to keep 914s.
although the same could be said of early 911s etc as well. they more or less sold everything they built including a lot of prototypes.

Yep! Tinted windshield. See below:

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@StarBear

Is this what the trademark looks like that you have? I managed to get a readable shadow on a piece of paper.

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I too have a Sigla w/s in my 74. It may be original - I have no way of telling. I do have the certificate for it that says tinted side glass. That really doesn't make sense to me that you could order only side glass that was heat absorbing? To me it should be all windows or none.

@wonkipop

It may well be that Sigla glass was installed at the factory too. I will have a look see... Maybe I can tell if any of the glass has a green tinge.

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@vitamin914
thats real interesting the way it specifically says "tinted side glass"
i did find that one 74 bumblebee that specifically said "tinted windscreen"
it has DELODUR 1 side glass. the screen was tinted but was a newer domestic brand replacement.

and then there are all the other more common ones i have come across that say
"tinted glass all round". those ones all have the infra-red windscreen and the DELODUR F side glass.

you probably could get exactly what you wanted if you actually ordered your car from factory versus taking one off the showroom floor. suspect the factory did combos of non tinted or tinted all round as stock for dealers, but would do specific orders for buyers who ordered a car from factory to their own spec. and dealers would definitely have installed a tinted screen in if it meant a sale. no big deal to tear a screen out and put one in for a buyer.

the yellow 74 2.0 that recently sold on BAT and belonged to one family (2 brothers) all its life and was verified as a very original car by a member here who knew the car its entirel life has the same window package as mine. untinted. F/F windscreen and DELODUR 1 side and rear glass. but it had no original window sticker or CofA in documentation.
thats the combo i am finding hard to link up documentation to. the variation that is on my car and is very common to a lot of 74 cars.
EDIT - in relation to comments below and evidence of SIGLA screens, the yellow 2.0 was a later 74 MY car. produced some time much later in 1974. think it was may or something like that without checking my file.

Yep, that’s what my windshield etching looks like. I have a POA for my car, will check if any tinting notation.

@vitamin914

i'm just looking at your certificate and date of car.
so yours is a 1.8?
as far as we can work out cars in that date band of nov 73 to end of jan 74 are all 1.8s

so there maybe is something there.
like maybe that batch of 1.8s that first are done from late oct 73 to some cut off point all got sigla screens. my 1.8 is late jan 74 build.

we might be on to something.
ah the mysteries of the 914. pretty funny.

EDIT
with that production date it could also be one of the last of the first batch of 2.0s that were done in 74 model year. its around that time they move into making the 1.8s which were late to get the 1.8 engine supply which does not happen until Nov 73.

@StarBear

thats great you have your "window sticker".
and very interesting the way it says just "tinted windscreen" specifically.
and it fits with the DELODUR 1 side glass being so called "untinted".

i'm thinking its def an original screen you have.

anyway. its pretty esoteric given cars lose their windscreens along the way.
but certainly the blanket statement that only sigla screens were original is incorrect.
looks like there are quite a few possibilities to make PCA judges choke on their weeties if thats your scene.

we just need @Van B to pipe in now.
he has a pretty original car - be interesting to know what glass is in his.
i think its a december 73 build car.

Here it is. “tinted windshield”. Side glass not tinted. Maybe that’s why they’re different?

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so this is the late 74 2.0 that was on BAT and very original car.
its a MAY 74 build. i just checked.

all the glass matches mine.
thinking this is your "non tinted" standard glass package.
but no CofA. or window sticker.
similar predicament to me.

i think what happens on BAT is people use the CofA or window sticker as a prompt.
they reference the option list and then go photograph everything that is an option to tick it off for originality. so "tinted glass" as an option prompts them to photograph all the glass. whereas your standard package doesn't prompt sellers to photograph glass.
hence i can't seem to easily find a nice neat CofA or sticker link up with the package of glass in the yellow one or mine for instance. spewing now original owner never kept that sticker. could get CofA but its a pretty dumb process these days and not worth doing.

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Clear glass was standard and the rear glass was always only clear. Windshield tint and side glass tint were different M-code options. A given car might not have had both options.

there you go.

------

for you blokes with sigla screens.
another one from the ECA/B research files.
may 74 1.8
pretty beat car, but original in its degraded state.
windscreen is sigla. could be original. who knows?
has CofA but one of the new ones which can't even tell you production date.
does not have tinted glass option listed.
side/rear glass checks out for clear.
sigla screen has different D code to @vitamin914 sigla screen.
also says S only above AS1. vitamin's says SGG.
@StarBear needs to take a close look at his.
are D code numbers same as this one as well as what is written above AS-1.


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Here ya go. Such a shame that I have the crack over the passenger defroster on my front glass.

@Van B



i think we might be on to something?

like there is runs of cars with sigla as supplier.
then other runs of cars with the kinonglas.

def a pattern here.

What about my rare Mexican front windshield?

now there is another whole can of worms.
replacement screens.
sure you wanna open up that pandora's box?

although it is interesting as a whole other discussion about the way manufacture shifted from the so-called western world from the late 80s on.
all the euros first went and shifted their factories into poland and other former communist euro countries and then shifted it again to china.
the story of our industrial decline bit by bit.
we used to get australian made screens for all our cars down here.
huge industry. now all gone and all the expertise that went with it along with the machinery. (we are gonna regret it i say?).

but back to the topic.
factory screens.
so far it looks like its either SIGLA or KINONGLAS.
and maybe date of production of car decided which?

@Van B and @vitamin914

that DOT 25 number on your screen is still on the current DOT list today.
they still exist as SIGLA or flachglas as its called.

whereas DOT 31 for kinonglas no longer appears. company is kaput, or absorbed into SEKURIT german gmbh these days.

@wonkipop

I have no idea what the original engine was. I was always under the assumption it was a 2.0... It was removed and reworked into a Weber carbed 2.4 L displacement by a California engine builder. This is the way I purchased it from the PO. I will look at the paperwork to see if there is any mention the original displacement. The badge on the back says 2.0 but that is meaningless because it has been repainted. I will go around and take some photos of the tempered trademarks.

I just turned 9 years old when the car was built, but I do remember it was the start of the oil embargo crisis and there were all sorts of issues getting building materials as my parents were having a home built. Could it be there were issues getting glass from one supplier and another, Sigla was brought in? It would be odd to have two different OEM glass makers tool up for the same part. Or Kinonglas didn't have the capacity for peak production of the 914? I wonder what was in the 75 and 76s?

4 pages ?
Sorry I can’t help myself…
Continue on ….

probably is a 2.0 - its right on that borderline.

i was 13 when mine was made. must be 4 years older than you.
born in 1960.

so far the few 75s and 76s i dug out of BAT are kinonglas.
i had a bit of 75 1.8 material on file from the 74 engine research.
and a few nice examples of some 73s. we were chasing the collection of engine stamp numbers either side of 74. those 73s had kinonglas.

could be a bit of old fashioned german industrial bargaining?
VW doing a bit of arm wrestling. maybe kinonglas put up their prices, so VW got an order from competition to keep em honest. that sort of thing used to go on.
fair bit of industrial unrest in germany at that time as well as fuel crisis.
one of those VW heads got into a fair bit of trouble with the unions and it caused his head to roll. might have been slightly earlier than 74 when that happened. but there was a bit of turmoil. so who knows.

it is interesting that your car is very close to starbears on production date.
as well as Van B's. so i would not be inclined to dismiss the sigla screens.
especially in the case of starbear. he drove his out of the showroom so unless he has had a memory fade, which is unlikely, thats the way it came.

i don't want to be rude.
but.....don't read it if you are not interested.

Hey, yeah it is boring glass... was an occupational hazard for me. No one is making you read it.

Be happy it ain't a thread about engine oil, gear box oil, tires or batteries... or who belongs to a spotted car

I think this thread is hilarious. I like to read the BAT auctions for 356's. Those guys are anal but entertaining. You guys are having fun with glass and interesting and entertaining. One can always learn something new about Porsches from threads like this.

yeah
we are just having fun.
i go nowhere near concourses and all that.
in fact i got a pm from @TJB/914 this morning, the guy who started this thread, delighted with our meanderings. he started all this with a perfectly reasonable question,
he wanted to reproduce a sticker for his windscreen and restoration. and of course, there is no right answer. but he is enjoying the info. if it helps him make a repro sticker well its a good thing. isn't it. we are just all out to have fun preserving and restoring cars - or as the case may be totally modifying them into monsters. all good

and sh#t i've just learned heaps from @vitamin914 about glass and windscreens i can take into everyday up to the minute purchases of screens for my other cars which are still newish and contemporary. fricken pricelss.

but @JeffBowlsby in his meticulous and careful way asked a few pages back the right question, linking DOT 31 to a manufacturer. can it be done.
well i've looked and looked and i can't reach far enough back in time to do that.
its just not there in the digital files of the Dept. of Transport USA.
but i can find a current list.
and i just cracked something with it that Jeff wants to know.

so DOT 31 is unfindable.

but DOT 25 still exists.

and i notice its on all the SIGLA screens.
but i wasn't looking hard enough at the side windows. pardon my lack of observation Jeff.
they are also DOT 25.

that means same manufacturer.
DOT 25 is flachglas Automotive GMBH germany.
still exists.
company website shows history.
they made the SIGLA windscreens. company history says so along with DOT number.
but obviously they also made the DELODUR side windows.
so the writing on those makes sense now.
DELODUR is made by flachglass (makers of SIGLA brand windscreens) and the DELODUR is a process or toughening technique patented by SEKURIT. in this case licensed from SEKURIT. so the LIZ. SEKURIT is clear in its meaning now.

so you have sigla windscreen and DELODUR side glass you have a car where all the glass came from Flachglass. SIGLA screens fitted to 914s makes perfect sense.

you have a Kristall screen made by Kinonglas - is a combination of glass from two companies. the windscreen from Kinonglas, side glass from flachglas.
at some point Kinonglas was sold to ST. GOBAIN/SEKURIT and disappeared from existence.
after 914 production finished. DOT 31 disappeared with it from the records.
probably if you looked around in a physical archive in DOT you might find an ancient list.
but who cares.

here is the current DOT list you can dig up.

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and here is a bonus for @JeffBowlsby .
came up randomly in one of my searches.
stuff that comes up i have no idea how it appears or how to back track it into some bigger DOT archived.
but its actually correspondence between SEKURIT and the DOT with an inquiry about just what they have to print on the windscreens and it dates from 1973.
more precisely the company is SEKURIT GLAS UNION GMBH.
its very clear too its referring to Kinonglas Kristall.
so in some way Kinonglas is hooked up to SEKURIT at that point in some kind of association or sub company.



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Absolutely fun. That is exactly why we are all here on this forum with our lovely little 914s on the driveway (or on jack stands) !!!

Poo poo to the naysayers...


@wonkipop

I looked at my 914s last night... Some interesting observations.

The 74 that has the Sigla w/s has DOT 25 (DELODUR) tempered glass all around. I think it is safe to say all 914s have this supplier (DOT 25) for all tempered parts. Then there are variations DELODUR -1 / - F / -1F. Not sure if we will ever figure that out.
What we should be doing is looking at the M number. That is recorded somewhere. Either at the manufacturer (for sure), but I would think they had to be submitted to the DOT, or the NHTSA for safety compliance. Question is, who could be asked to dig up 50+ year old records...? I'm sure they must still exist in a filing cabinet somewhere...

The 74 has M173 (-F) on the sides. This is the tinted glass EXCEPT for the left side large door glass, it has M202 (-1F). To me that means it has been replaced somewhere in time. M202 would be a different piece of glass - likely either the tint composition / raw glass supplier or the thickness. The back window is M93 (clear glass).

On the 73, the tempered glass is M93 all around meaning it is all clear glass.

So the takeaway for me is you could order heat protection glass for the windshield, side glass (M173 or M202 for tint and M93 for clear) or a combination, but the back glass was always clear M93 (M930 with a heating grid).

Indeed. As we say “ mostly harmless”, though my wife adds “amusing” as she rolls her eyes…..

@wonkipop
Yes, those are the same sub-markings as on mine:
SGG
-AS1
Exact match, though mine is fainter and doesn’t show up when backing paper used. Might try a colored (red?) piece of paper.

@wonkipop Unfortunately my windshield was replaced many years ago. All my other glass is orginal though.

some more trivia you don't have to read

SEKURIT.

patented process for making toughened glass.
process developed by Saint Gobain and licensed out to other glass works.

in the case of 914s St. Gobain licensed SEKURIT process to Flachglas GMBH who branded the product as Delodur.

Later on Saint Gobain morph the name SEKURIT into a brand that covers their automotive glass division.

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re SIGLA screens also made by Flachglass.

S = sheet glass. thats the clear version. two layers of normal uncoloured sheet glass, virtually clear glass.

SGG = sheet green green. ie two layers of green coloured sheet glass. thats the "tinted" version.

the SGG is the one all the early 911 guys want because its the very greenish windscreen they covet.

seems to indicate that Flachglas was making their screens from plate glass stock (aka sheet glass).
whereas Kinonglas were making theirs from float glass stock (at least from 74 on).
the more modern way to make a flat piece of glass. earlier kinonglas windscreens use the S abbreviation like sigla do. later (approx 74 on) ones use the F.

i won't be digging into earlier than 74.
only interested in 74 1.8s.
anyone else wants to know what goes in earlier cars can do their own searching if they care about getting into windscreen fetishes.
but i did discover the early 911 guys are getting vintage screens re made by pilkington who now own the SIGLA trademark (brand), Pilkington will make you a replacement reproduction screen. you got to put your money down, all of it prepaid, with no return or order cancellation, wait three months and you get one. don't ask how much, you don't want to know. but if you think vintage tyres are expensive. mere pennies.

you are dead right @vitamin914 .
DOT 25 - all that comes from flachglas gmbh.
they do all the toughened (tempered for Jeff) glass.
branded as delodur.

and also the sigla windscreen you have. DOT 25.
you have a full flachglas car mate. pure breed. it would be all original glass that one.

i've got the factory cross bred mongrel.
with the DOT 31 windscreen. kinonglas.
swallowed up and disappeared a long time ago into the Saint Gobain empire of world domination. that company must have no cheese eating surrender monkeys on the payroll.

EDIT
ps your one piece of 1F sideglass is the glass they started using in 76 for tinted instead of F. supercedes the F i think. so its had a broken window down the line and the replacement glass has probably come from porsche as the new part.

yes on the "tinted" windscreens too being properly described as heat protected.
the SIGLA looks like it did it with both laminations being a green glass. SGG
the KINONGLAS did it with only the outer lamination being IRA (infra red absorbing) glass. FIRA/F.
clear versions of the windscreen are notated with an S for Sigla and with F/F for Kinonglass. i have to get my F/F out in the sunlight to see the colour. think its a kind of bluish grey rather than ultra clear - so even the "clear" or standard kinonglass one is kind of darkened. but hey i am probably color blind.

Now does sekurit still make replacement glass? That’s the question!

a titbit at the end for the front badge conscious.

strange triangle mark on SIGLA windscreens,
looks like a british standards safety kite mark,
isn't.
its the porsche logo that porsche had imprinted on all factory installed glass.
never realised it until now. don't know if any other nerds here had ever picked up on this totally useless bit of information. its pretty unique to the glass. don't reckon i have seen this elsewhere on 911s.

its a stylised P inside the triangle.

from @Van B 's screen.

Click to view attachment

from a 70s 911 rear glass. there on that.
and its on all the SEKURIT side glass of 911s.

Click to view attachment

from a 70s 911 with a sudglas screen, not even made by same company as SIGLA.
completely disassociated manufacturer but a factory supplier for small numbers of 911s screens.
there it is.

Click to view attachment


everybody else who had their logos on their siglas.

VW

Click to view attachment

MERCEDES

Click to view attachment


------

the lucky bastards with the SIGLA screens have got 1% more porsche in their VW porsches than us guys who missed out and copped the VW branded kinonglas.

Wonkipop. That logo is all over porsche parts. I laughed when I bought 991 control arms. They were made by TRW but each one had a conspicuous little grind mark… which was the aforementioned logo. So, thats the difference between an OE and TRW control arm… about one gram lol!

i've got a windscreen from 92 in a box thats genuine porsche.
but you will have to find out who makes that or made that then until i have someone help me get it out without breaking it.

will at least tell you who was making the screens 15 years later for spare parts.
dunno if you can still get side glass from porsche. probably NLA.

right. i don't know enough about porsches. i have not spotted that logo anywhere else on the 914. (and don't own a 911) maybe its there engraved into things i just have not spotted on my car. most of the stuff i have pulled out like the little flywheel washer etc have been stamped VW.

just had a quick look through some of the more accessible bits of the stash.
pretty amazing how many parts don't have the P.
front tits. no P
front indicator buckets. no P
but an early steering wheel i have - i noticed it there. tiny.
would never have looked twice at it.
i just went on their website here and i see its their big claim - any genuine part will be stamped with it. the tits and the indicator buckets are genuine in boxes from 30 years ago.

How is Kinonglas pronounced (phonetically)?

Kai-non-glahs?
Kihn-on-glass?
Koi-non-glahs?
Keen-un-glass?

@sirandy

@JeffBowlsby

Kee-non-klaas

@JeffBowlsby just looked through your option code list on your website mr. b

great list - despite your apologies for missing data.
https://bowlsby.net/914/Classic/OpEq.htm


4 windscreen and side glass option codes.
might explain SIGLA screen v k-klass screens?
but can't link up specifics to the M codes.
def enough option listings to explain existence of both sigla and k-glass in 914s from factory.
maybe not random supply chain stock but rather deliberate option (and standard) selections?


M089 tinted glass.

noted as standard on 71 914/6 and 73/74 2.0 (some gaps in data for years as you note).


M568. green tinted side glass.

this 5 series number is listed on your 400 series group. is it a typo and its 468?
you have an X marked in the table for 74 2.0 and 1.8 but no other years.
(not sure what you indicate by the X.)
curious description = green.


M567. lam tinted windscreen.

optional for 71 914/6 and /4, 73-75 2.0 and 1.7/1.8. no data for some other years.
but 73 and 75 seem to get same.


M568 lam tinted side glass.

available as per M567.
reference to lam tinted probably incorrect? likely toughened?
normally you cannot expose the edge of laminated glass, the interlayer will fail.
makes no sense as practical application - also we have not come across any?
just option F code toughened side glass (delodur).


thinking SIGLA screen might be the M089 option?
appears early in the option number codes and was around in 911s of that exact time.
its the green screen 911 guys want these days for their restorations.

maybe why you get these sigla screens appearing alongside k-glass in the 74 cars we have looked at. if your table is right, 74 2.0s had one of those "tinted" screens standard (sigla green?) and one was an option (k-glas infra red). or other way around.
and for 1.8s a clear screen was standard (either sigla clear or k-glass clear) and it looks like you could get either of 2 tinted screens as an option?

what i am seeing is that 74 2.0s all had a tinted screen in our small selection of data.
one or the other (sigla or k-klass). but have not come across a clear.
found clear of either type in 1.8s and options for either type tinted in 1.8s.
have not gone into other years much except for 75 and 76 2.0s. but all are tinted screens i have found.

I reviewed that page too the other day and have the same issues/questions. That webpage was developed based on english language versions of printed Euro brochures by model year which included the optional equipment offerings for that year, price lists that used those same words on the webpage to describe the item and pricing.

The description wording is quirky and thet M568 item is listed 2x. Id est quod est.

I dont have the reference brochures anymore or cannot seem find them easily.

doesn't matter i think because its priceless information good enough to crack the PET page Jeff.

Click to view attachment

3 windscreens with same part # and only 2 for USA but specific about which models.

M 089 is the first one on your list. its got to be the 6s and the 2.0s got the green sigla screen (SGG) as standard. its not really tinted. we think of it as tinted but its just darker green glass.

the standard clear glass screen is not an option so never appears on M list.
is the second one on the PET list with the same part #.
could be either a sigla clear (S) or k-klass clear (F/F). standard on all smaller 4s.
agrees with PET description.

third one with same part number is toughened. we have never seen one.
never be on a USA car. (and if 914s had ever been sold in AUS, then AUS would have been on the exclusion list too). not sure what brand. you would have to sight one to ever find out.

fourth one with the different part # described specifically as heat absorbing glass is the IRA screens we are seeing. that is heat absorbing glass. by kinonglas.
be either IRA/S or IRA/F or FIRA/F depending on year.
thats the screen you could option up for any car in any year.
there is a 6 with one on this thread back at page 2 or so.


@TJB/914 asked a good question i think.
because if you were doing a resto you wanted to be accurate, you would never fit a "clear" screen to a 2.0 or a 6 if you were after accuracy. they never had them by the looks of things. probably if you are doing a 6 and you wanted to be right on the money (and they are worth enough these days) you would be doing the same thing as the 911 guys and going after one of those green sigla screens.
so if you are going to make a stencil and you can bothered going to all that trouble you may as well get it right rather than fake history and getting it completely wrong.

or just as legitimately, don't even worry about it and just keep improving the car.

PS to clarify what i mean by a "clear" screen.
what americans think of as tinted is not the same as the germans.
they did not really call it tinted in technical terms - like for the PET.
a green sigla screen is clear for the sake of PET but described as tinted in options.
a less coloured sigla or kinon is clear for the sake of PET also.

and a heat absorbing screen isn't really tinted either but its described that way in options list. they don't seem to use the technical terms for the showroom option descriptions.

hence you get confusion. and there appears to be two different so called tinted types.
but whats going on is that the 6s and 2.0s are getting those classic sigla green screens as standard equipment in my humble opinion. but the lower down the food chain small 4s are getting the "ungreen" screens as standard. and its being described in the PET that way. and if you ticked a box for tinted in the USA in those later years you likely got upscaled to the IRA screen.

There has been some great work done here guys, many thanks.
To clear up the M options for tinted glass, there were only 2.
M567 for tinted windscreen
M568 for tinted windscreen and side glass
The clerks preparing the CoA/PPS have an incorrect crib sheet for M568 and you often see it as side glass only or tinted glass all around. The latter is the description for the 911/912 that does have a tinted rear window. As stated previously, the 914 rear glass did not have a tinted option.
M089 for windscreen in clear laminated glass (Windschutzscheibe in Verbundglas) not in conjunction with M567 or M568
Basically 3 windscreen options:
914 541 101 10 windscreen in clear laminated glass for all models North America & Sweden, available elsewhere as option M089
914 541 101 20 windscreen in tinted laminated glass for all models North America & Sweden, available as option M567 or part of option M568
914 541 105 10 windscreen in clear tempered glass for all models, except in North America & Sweden
Note there is a typo in the PET diagram where they have 101 instead of 105 for clear tempered glass.
Also, the options choices mean that to get tinted side glass it came in conjunction with a tinted windscreen, or you had to purchase as spare parts and install yourself.

condensed version over in originality section.
just data without wandering/waffling.
incorporating and adhering to verdict from dave p.

but we had to wander to get back on the narrow path?

http://www.914world.com/bbs2/index.php?showtopic=363328