Self destructing fixings rant

[Luddite]

While reading of the issue squelch has to attend to on his GTS and noting the corrosion on the fixings had rattled my cage once again..

www.911uk.com/viewtopic.php?t=149209

I too am a worshipper at the alter of deMort, but it seems we may disagree on the justifications for using the self destructing fixings Porsche seem to have been using since the 80`s onward..?

By way of an explanation, over many a year I even bought Porsche packaged nuts, bolts and screws, all of which were either plated or treated in some way which I can honestly say were of far superior quality to some of the fixings Porsche seem to utilise today in some locations. Back in the late 70`s while nailing my rusted out old 60`s 912 back together, the way that screws nuts and bolts which I expected to snap suprisingly loosened off, was that which drew me into the Porsche fold as an admirer of quality engineering when compared to all other of my vehicles which I had worked on up till that time...

Yeah early Porsches rotted like most other cars around at the 60`s and 70`s, but there were definite signs that someone with engineering priorities was able to make decisions at Porsche, as opposed to the bean counters...? Looking at the self destructing fixings utilised in various locations on my 991 and the history recorded here on this forum of the requirement to make use of jigs, drills and taps to resolve issues with fixings, that for me should present little or no issue on a high quality machine. Not being a metallurgist, I would not care to promote alternatives but I would like to think that perhaps a few extra Pounds spent at the time of production on incorporating higher quality fixings would save a fair bit of pain and grief for the legions of enthusiastic Porsche owners around the world who put so much into the repair maintenance and restoration of their older Porsches, which I suspect allows Porsche to oft times boast of the high number of Porsches still in existence or in use compared to other marques..?

Yeah well you may think that if fixings can last ten or more years then that might seem reasonable, but not for me, not only given the possible expectations of the possible lifespan of a Porsche, but for fixings to decay well ahead of the exhaust system suggests that perhaps the selection of materials could be improved upon...?

OK, OK so tell me I`m wrong, and that RUF or Singer or any of the high quality manufacturers/re-manufacturers use only original Porsche fixings to hold their exhaust or other components in place...?

Whadaya fink... :thumb:

 

[Robertb]

I don't disagree, but its hard to imagine the pressures of running a car company.

I read an article by Richard Parry-Jones who was in charge of the Ford Focus development. They developed a special rear suspension system that he said to management would transform the handling of the car and set it apart from the competition as a great driving car but had to really fight to get it adopted. The additional cost? £25 a car.

Similarly, times were so hard at Porsche post the 993 that the 996 team had to beg to management to find the money for an electric rear spoiler.

Put another way, an extra 3 Euros per car on quality fixings would have increased production costs by nearly 1m euros over the life of the 991.

 

[911Time]

The main reasons for 'self destructing fixings' are, in reverse order:

3) The Pursuit of Profit: As you mentioned, the 'Bean Counters' have become more and more powerful (not just at Porsche) - so an engineer might want to specify a particular material, or finish but is hamstrung from doing so by the budget that's been allocated.

German brands such as Porsche, Mercedes and BMW used to be massively over-engineered - their reputation for longevity was built upon it but that hasn't been the case for 30+ years - sadly for us.

2) Salting UK Roads: We might be getting milder winters generally but when it does freeze, the combination of salt and wet roads makes for a very corrosive mixture and salt hangs around on the road surface, long after the ice/snow has melted.

1) Changes in Metal Finishing: Many of the surface treatments that used to be applied to metals, have been banned over the last 10-15 years, due to health & safety issues. Electroplating that used to include Hexavalent Chromium or Nickel were found to be carcinogenic and were (quite rightly) withdrawn.

Unfortunately, the replacements were nowhere near as good at resisting corrosion and withstanding salt-spray testing (the industry test for corrosion resistance).

Exposed underbody fixings and especially those subject to repeated heat cycles like your exhaust fixings, get the worst of all conditions corrosively speaking.

Companies like Ruf and Singer aren't constrained by the bean counters and sell cars for £££££s, so would simply use corrosion resistant metals like Titanium or Inconel for their exhaust parts.

 

[deMort]

I'm just going to add fuel to the fire here with a few images ..

964 ... over 30 years old with 106,000 miles on it !

Exhaust manifold nuts came undone with no issues .. on the casing i think i can almost see some rust on X1 nut .. you can actually see some of the original wax oil on the engine .. after all this time it's still there .

To be fair this did have an engine cover .. well sort of .. but it illustrates what Luddite is talking about ..

996 onwards and there is usually very heavy corrosion to anything exposed ..

But as 911Time rightly says ( and i agree with every word ) .. its cost and our climate ... Dubai cars don't have rust issues !


For any garage working on these though .. we Have to use Porsche parts .. there is simply no way we could source well over a hundred different types of bolts for every model of Porsche and be safe knowing they will last longer and not break !!!

Things like exhausts and yes all of us Indys use different fixings , stainless .. but that's about it i'm afraid .


squelch ... his bolts will come undone with no issues .. that's just surface corrosion and the bolts themselves won't be seized in place .

No need to worship at my alter young man .. you have a direct line via the PM system lol ... bless you though .

 

[Dizzy991]

Not to mention pump covers, cooling pipe fittings etc etc

 

[Luddite]

Sorry Robertb, I think slightly differently to you in this regard.... I fully acknowledge the difficulties that all sorts of industries have faced over the years, but your justification for "cheap" fixings does not work well for me.

Re the Ford Focus, which is a mass seller competing in a tight sector of the marketplace, and in past times perhaps likely to be binned after fewer years than the average 911...? But then you were typing of suspension upgrades that might cost an extra £25 per unit, which would likely be seen as of no real interest to base model Focus buyers or perhaps even to the classy end of the focus market, but if you said to the Focus RS/ST buyer it might cost him/her £250 extra to have even better suspension performance, I suspect that could be no real issue..?

For sure the bean counters seem likely to look at justifying every bean spent over the mass of the market to average things out... My expectations of Porsche as I knew them in my air cooled days, far exceeded that way of operating..

Mark, as I typed my 912 was a rot box, but as best I can remember, every nut bolt and screw came undone, be that in the electrical system, holding the fuel tank, suspension strip down, trim, engine strip and even exhaust to cylinder head fixings..at the time I think my 912 was perhaps 10 years old and being a West of Scotland car, I suspect it may have seen its fare share of salt during it`s lifetime..?

Your thinking on the health issues relating to some methods of plating works well for me, H&S complicated many industrial processes by increasing costs, though I think today and perhaps for many years it may be simple enough to buy "high quality" exhaust manifold fixing kits for a couple of hundred Pounds, and were I buying fixings in the numbers that Porsche does, I suspect I would be paying much less than that per unit, and the customer would end up be paying very little extra to buy a higher quality product..? Would say an extra £1k added to the price of a 911 put folk of, and how much do we imagine it might cost to use higher quality fixings on the exhaust system, heat shields, coil packs and/or any other area where fixings currently create issues...?

No argument from me on over-engineering of the past in many areas of industry, but my old 912 was a rot box and the fixings came undone..

I worked in industry for 50 years, and witnessed the explosion in risk management, down sizing and delayering, with the main aim of cost cutting in it`s many and varied forms, along with the tactics employed to make it all happen... :dont know:

For me the bottom line is not the oft used excuse of extra cost in overall production for Porsche to fit a higher quality widget... In the end it is about customer perception of QUALITY when supposedly buying a HIGH QUALITY machine, the customer happy to buy into the brand and pay an above AVERAGE premium for a machine that rightly is expected to be better than just AVERAGE..? A Porsche seems likely to be cherished and enjoyed over thirty or more years on from it`s date of first registration, perhaps having passed through the hands of many owners over that period of time...?

For sure Singer and Ruf are very expensive machines, but to resolve the self destructing fixings and still show profit, seems unlikely to add much to Porsche pricing...? That typed, there are folk out there spending large amounts of time money and energy on their old Porsches of many types by fitting expensive stainless exhaust systems and other shiny or carbon accessories to improve on the perceived quality of O.E.M. kit..?

deMort, thanks as ever for supplying an less than biased view combined with your much valued experience and real world examples of old style engineering quality Vs what seems to be not much more than cost cutting techniques..? I can totally understand the logic in using Porsche parts, and the likely risks of promoting the use of fixings made of the latest wonder material that the Porsche community have been sold the idea of, and that could turn out in time to be a catastrophic failure..? For sure using Porsche parts for a business is a much safer option should any so related future problems arise, as it seems they can on occasion..?

Also good to find out from you that the fixings on squelch`s water pump pipe seem likely to come out without shearing, unlike the manifold to head stud saga`s that so many seem to have to get involved with in time..

I have in the past made mention of my old alloy V8`s use of stainless steel manifold to head bolts which after 20 years and circa 28k miles of use, when tested, came undone without issue, as did the manifold to the next two into one section of the exhaust system.... Also worth noting is that there are different grades of stainless steel, and marine grade (316?) may be more salt resistant han the other variants. Also worth consideration is that my old V8 seems likely to have larger diameter and perhaps different thread pitch than a 911, and that the likely the normal running temperature of my pre Cat V8 will be lower, and as not quite exposed to the shocks of splashes generated while driving in the wet as a 911 exhaust might be...? Thus I as previously mentioned I make no recommendations for an ideal replacement for the self destruct fixings that Porsche seem to utilise.

Were I to assume that the material Porsche use was well researched to be ideal for the task it performs, but is understood to have self destruct properties in time, then my expectation might be that the fixings would form part of the maintenance regime to be replaced before a time when they were likely to shear off, or loose their ability to be replaced with minimum fuss... ?

As ever I am very open to being proven wrong, in the hope I might learn something...

Whadayafink... :?: