DDK - Die Deutschen Klassiker

The grain texture as I said earlier is from forging (some interesting links below for anyone who’s interested)
Bolts are generally cold forged up to M30 when they swap over to hot forging.
As an engineer I’m always cautious of machined bolts (I had an interesting test case a few years ago where I got TUV involved in an aftermarket wheel bolt being sold in UK - by a very well respected vendor that shall remain un named - for the Boxster & Cayman where I found the yield strength of the bolt to be ridiculously poor & in my opinion damn right dangerous).
Mark, just looking at Kev’s pictures makes me suspicious of the manufacturing process. The part number 91436131502 on Kev’s box is the same as the new dull bolt that matches my originals, but as I said earlier the manufacture & finish suggests it’s a different supplier. From the PET, Mark, it seems the steel wheel bolt is 183601139A which is a VW part No for Type 3 bolts.
Stuart, sounds like you have the same bolts as mine.
Anyone got any like Kev’s?

https://www.youtube.com/watch?v=BI8LZHwCEsw

https://www.youtube.com/watch?v=3kxcw08p_oY

Today I took the wheel bolts to the blasters and got all the heads cleaned up and textured evenly to remove the socket marks before dropping them off at the zinc platers.
This evening I stripped the old FI throttle body down. The spindle holding the butterfly valve had a lot of wear and play in it and initially I thought it was the body but when I took the spindle out there is a big step on the shaft on both ends (looks like a mini camshaft), plus wear in the holes of the body. These will need replacing.
I spent the rest of the evening cleaning up the other parts and bagging up the lever assembly to take down to the platers when I pick up the wheel bolts to get them freshly gold zinc plated.

2nd video is ace, been a long time since I've seen the process, thread rolling is a brilliant idea.

Will your wheels ever come back? Never allow a specialist to 'relax'!

Got home late last night from work, after cooking my super and before calling it a night, I dug out many of the magazine articles, sales brochures and photos from when the 914 was still in production. I then studying them to see what the alloy wheels bolt finish looked like on the optional fitted alloy wheel on the 914-4.
Most of the photos are black and white and the best colour detail photos to show the results are found in the many 914 sales brochures printed in Germany and the USA.
This is what I discovered:

Back in 1970 the first alloy option available was the Italian made Pedrini which was available till the early 73 model year. The wheel bolts finish is bright.



The Fuchs wheel was first introduced in the 73 model year for the new 2.0. When looking at the wheel bolts they have a bright finish.



Looking at the wheel bolts on the impact bumper 914s introduced from the 75 model year in 1974 the alloy wheel bolts have a duller finish shown here on the Fuchs and Mahles that replaced the Pedrini wheels sometime in the 73 model year.



Often some changes during production came in during a model year not just when the new model year was introduced. The finish on the alloy wheel bolt could have changed due to the supplier changing or from cutting the cost of making them.
Due to the alloy wheel bolts being exposed to the elements, brake dust and taking a bit of a hammering from the socket when the wheel is removed and refitted. The thin layer of platting was effected and over time the bolts lost their look. If a too strong wheel cleaner was used this could also affect the wheel bolt plating.

The standard wheel bolt had a dull finish and up to the end of the 73 model year the hub caps protected them. From the 74 model year the standard wheel bolts heads were protected with a plastic cap.

Darren I total agree with you that my ONS wheel bolts I have are not made like the originals and are probable made by a new supplier and the box is dated from memory around the mid-80s. I new you would spot this
The one you bought from Porsche recently is different from any I have seen before as the forging process left them with a very noticeable pitted look, much more than centre flat cap section that doesn’t wear anywhere like the outer edges on the wheel bolts I have on my cars. Will have to remove the old wheel bolts off different 914s I own to see how much difference there is between them!
The bolt shank on your bolts is far too long, the shank is a lot shorter on most and the flat to head dome edge is a lot more curved on my wheel bolts like in the photo of the yellow 914 and the new one from Porsche. Your bolts don't have much of a dome.
I also very much enjoyed watch the videos while taking a few minutes break to eat my sandwiches!

Thanks Kev,
That’s brilliant information there. I do tend to challenge everything in life and never take anything for granted. You’ve certainly given a comprehensive reply!
My cars a mid 74, so it fits with your theory on dull bolts and they certainly look the same finish as your bottom left photo (green car with Fuch).
I agree with the excess wheel cleaners, some contain phosphoric acid (like wonderwheels) it can “blacken” zinc.
BZP (that’s Bright Zinc Plate, for those not in the know) tends to be a thinner (below 15 micron) process and does rust easier than dull zinc. (There really isn’t any difference in cost of the process in mass production, only the base metal needs to be better finished to take BZP over dull zinc).
Just a theory….maybe Porsche changed in later years (plus introduced cover caps) to hide/prevent rusty BZP bolts or reduced costs with a less smooth finish on the bolt prior to plating?
All interesting Anorak stuff

Anyway, on to tonight. I’ve been indulging in a little selfish Imagineering……..

Sorting out some very thick 316 stainless plate I spent several hours hacksawing by hand, this.



To be continued……

Darren C wrote:Thanks Kev,
That’s brilliant information there. I do tend to challenge everything in life and never take anything for granted. You’ve certainly given a comprehensive reply!

I have gathered that some time ago.

I spent this evening looking at the long wheel bolts that hold on the alloy wheels fitted to a couple of my 914s. Afterwards I headed to various storage units to hunt down the wheel bolts removed from various project 914s I have, to see if there were any differences.
All of mine on the screw thread tip are marked with the VW logo and K X, the earlier ones are not as well stamped as the later ones.
Original short bolts that held on the steel wheels have the VW logo stamped on the head outer surface.

The best conditions long wheel bolts I could find were removed from a 75 model year 2.0, dull plating covers the whole bolt.



The rest of the bolts I could find, the heads have lost most of their plating.



On a few when you look at the radius you can see copper plating and on the crown, but on the shank there is no sign of copper. It looks to me that the bolts heads were plated only in copper and then plated over with the finish. Later bolts I can’t see any copper at all.



Darren the long wheel bots you removed from your 914, do they have any markings on the thread tip?

Thanks Kev,
There looks to be a difference in the length of the Hex head & plain unthreaded shank length too.
The copper is interesting, plating steel first with copper then zinc can create a Zinc rich Brass! Are you sure it’s not (and I’m sure, you’re sure) residue of copper grease put on the threads that’s been compressed onto the dome washer over the years under the pressure of tightening the bolt (I have to ask)?
Is it on the hex flats too, can’t tell from your pictures.
My bolts are down at the platers currently, I should pick them up tomorrow hopefully. What is certain is that the thread/plain shank length does vary between the new bolt and my originals.
It seems to be, from this small insight, that there are multiple versions of the “same” bolt in the supply chain to Porsche.

Judging by the time of your posting Kev, I hope this isn't giving you sleepless nights

Darren C wrote:Judging by the time of your posting Kev, I hope this isn't giving you sleepless nights

No, I'm just making a full use of the day.
No LED lights going flat excuses here to bail out early! Mine are wired to a car battery!

There is copper on the sides and on the dome, maybe the finish outer plating was a thin layer of chrome on the early bright finish bolts.

There are two different thread lengths on my bolts, the shank varies from 5mm to 10mm.

Darren take a closer look at the photo of your two bolts removed from your 914, they are not a matching pair, the one on the right looks correct as its the same as the bolts I have, the head on the one on the left is different, the flange is smaller and the dome is flatter!

Darren C wrote:


To be continued……

Kev

I think Darren has gone a bit mad with all this talk of wheel bolts and has gone into making modern coathangers

Or could it perhaps be a bling exhaust hanger!!

nrc914 wrote:

Darren C wrote:


To be continued……

Kev

I think Darren has gone a bit mad with all this talk of wheel bolts and has gone into making modern coathangers

Or could it perhaps be a bling exhaust hanger!!

Looks more like a bird with open wing span... but the head broke off due to Daren get carried away with the sawing!!!

I think chaps that you will find it is called a "pocket reminder."

He puts it in his pocket to remind him to start on my car next.

I got up real early this morning and found some scrap metal in my pocket that looked like a bird with no head, it was quite ragged on the edges so I went into my shed and spent a couple of hours before work filing it down.

Kev, I think it’s a trick of the camera, the two bolts are the same, I compared all 15 and they are pretty much like for like with the exception of the 16th which is the new one. I hope to get them all back tomorrow so I’ll post a picture.
Great collection of old bolts you have there. There’s a program on TV about compulsive obsessive hoarders, I’ll post you an entry form (one came with my Embarrassing Bodies application)

Anyway tonight after work I continued to file, drill and fettle that piece of Stainless plate until it was a reasonable match for my cornflakes box imagineering template.



If I could only remember what is was for?

Darren C wrote:

If I could only remember what is was for?

Darren, let me remind you!
Once you put the six folds in, this bracket will mount to the top of the crankcase via two tin-ware screws and a bolt that goes through the crankcase.

Realisation of your premonition, a nemesis during conception

(cue the psycho shower music)

Blimey, your going to attach it to the crankcase and then put it in your pocket to remind you to do my car next?