DDK - Die Deutschen Klassiker

scalino65 wrote:my car is orange.. ....also very popular in the 70s.

Very nice. Second best colour for a Carrera.

Ferry Man wrote:The duck tail helps plant the rear, markedly so – no denying that - but configured without a front spoiler the front end lift is actually increased slightly (you can tell I’ve been reading my ‘Konradsheim’ book).

Porsche soon realised that and evened up the aerodynamics of the cars (in the '75 model year, largely because the rear spoiler got bigger that year and the need for a front spoiler became more urgent).
I will be following that more balanced configuration.
The ducktail + front lip spoiler combination looks good and works well.
These days most people install the front spoiler on the ’74 cars because you won’t enjoy high speed motoring with a duck on the rear and no front spoiler fitted.

Paul, What needs not to be overlooked is that the front valance is actually a 'spoiler' in its' own right with a lip shape at the bottom which reduces front lift by approximately 40% . This was also true of course for the valances fitted to the 2.4S and the 73RS. The front rubber lip was added only in conjunction with the whaletail which reduced lift far more than the duck. When the rubber lip is fitted with the ducktail it increases rear end lift due to a pitching moment about the front axle. I believe the duck without rubber lip is therefore the more balanced combination.

Guy wrote:the front valance is actually a 'spoiler' in its' own right with a lip shape at the bottom which reduces front lift by approximately 40% . This was also true of course for the valances fitted to the 2.4S and the 73RS.

Guy, you may be correct but I don't see any 'lip' on the standard valance.
Yet that was evident on my 2.4S front bumper (and on the RS).
The '74 valance appears to me to be pretty much devoid of any dam or barrier to airflow going straight under the car.

But I concede I may be wrong. I must read my 'Konradsheim' book again, I recollect many examples of the various premutations listed within the RS bible.

Now look at what Mike has started....

Ferry Man wrote:
Now look at what Mike has started....

That's pretty much why I asked the question because of the wind tunnel experiments in the 73RS MY concluding rear and front have to be balanced. I would have thought that such attention to detail must have resulted in a duck and a duckless front matching spoiler or at least a compromise that works with both in the 74RS. I bow to guy's knowledge on this particular model so I still want to keep asking and learning. Without the knowledge I just have to keep wondering, with all these combinations of airflow and metallic colours available, perhaps Porsche made it more complicated than it needed to be. Just two years earlier Porsche nearly made the 73RS in one colour only.

I think I have a 74 front spoiler, maybe NOS, but I could be wrong, it's years since I looked at it. Now you have put up these comprehensive photos I will dig it out and check it out ( but then again you probably have enough metal lying around)


Regards
Mike

[quote="Highfield"]How does the glass duck attach to the metal frame ?[/quote]

Been snoozing and missed a bit...Thanks very much for the compliments, but I'm sure I got the better deal in my car livery

The GRP is bonded to the alloy frame with Sikaflex which whilst highly stable when used properly also eliminates gaps and makes a permanent bond. I then use GRP to wrap the duck edge onto and over the frame building an edge which can be trimmed to get good panel gaps and prepped for paint. I've done a few of these now both to repair rusty steel frames and fit alloy ones. I can confirm the frame used this time is the best one I've worked with. I certainly hope that the latch arrangement has come out ok since I didn't have any reference and the old frame fell to bits

I,m really glad to see its final home is such a nice car...

Andy

scalino65 wrote:I can add something here....the cars that came without front lip rubber spoiler jobbies, used the same front spoilers that included the bolt holes for the rubber lips. The holes had little plastic cap things in them to cover the holes.

Sweet factage bro.

My car has a factory duck :



When I got it there was a rubber front spoiler :



Which I thought was wrong so started to take it off but noticed the holes in the valance were very factory-looking so concluded the rubber lip was factory too.

Sounds like not.

haasad wrote:

Highfield wrote:How does the glass duck attach to the metal frame ?

The GRP is bonded to the alloy frame with Sikaflex which whilst highly stable when used properly also eliminates gaps and makes a permanent bond.

Andy

Andy (sorry for the o/t Paul) - I have just used SikaFlex / SikaBond to glue down my hall engineered flooring ! Is it that stuff ?

Ian

[quote

[/quote]

As can be seen M473 for 1974 model year was a rear spoiler (ducktail) only

What year(s) is this from please? Paul, once again sorry to hijack.




Regards
Mike

Andy (sorry for the o/t Paul) - I have just used SikaFlex / SikaBond to glue down my hall engineered flooring ! Is it that stuff ?

Ian[/quote]

They make loads of adhesives the one I use is specifically for bonding grp boat parts and bedding its 291i. Can't comment about using flooring adhesive ...sorry.

Andy

210bhp wrote:What year(s) is this from please? Paul, once again sorry to hijack.




Regards
Mike

Looks like a '74 to '83 front valance after which front fogs were built in.

OK, thanks for the fascinating diversions and the 'duck & front combo' chat.
I really like your anecdote Guy about the original owner sacrificing his ducktail with his desire to have a rear wiper. Not a lot different to speccing an RS with a sunroof I guess.

Anyway, as I volunteered at the outset, I am fitting a front spoiler (because I think it wise) although I concede it's wrong for a '74 car. And you can always unbolt it easily enough.
The car is for driving though, it's not destined for the show field (it would be directed to the public car park anyway) so I will fit one and hopefully it will serve me well once I'm thundering down the Autobahn.

Plus I've alreadly shelled out two hundred and fifty of my hard earned GBP's buying one.
Needless to say it's genuine Porsche.

Quite why it has '73' crayoned on it beats me?
And - a little curiosity for you - Porsche call 'em BUGSPOILERS.

scalino65 wrote:I can add something here....the cars that came without front lip rubber spoiler jobbies, used the same front spoilers that included the bolt holes for the rubber lips. The holes had little plastic cap things in them to cover the holes.

take that, carrera front spoiler fact fans!

Although mine is a much later car it left the factory sans front and rear spoiler. I added the rubber front lip the other year and had to drill the mounting holes.

I ran with a duck but without the front spoiler for a good while and I think you'd be hard pushed to notice any change in handling characteristics, I certainly didn't end up going through a hedge backwards.

There's been a few really rotten 911 shells saved and documented on DDK.
The worst are invariably UK, RHD cars.
Amongst such vehicles are the '70 ‘S’ of Dr. Mark restored by Barry for Canford Classics (formerly known by me as 'the swamp car' - that tells you all you need to know) and the '67 ‘S’ belonging to Garry (visualfx).
Both of those cars should - strictly speaking - have been pronounced 'write-off', and yet caring owners were prepared to pay and keep them on the road.
Well, now there's another rusty RHD car being put back on the road.

The shell was delivered to Chesterton's and they set about pulling it apart.