"ZanziCup" : From Sow's Ear to Silk Purse.

JamieG said:

Evening Henry, another cracking thread about your fabulous car. Glad to hear you have been out enjoying the brute. Please keep these threads coming! (PS - think I missed my chance with your old Manthey-car )

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Email sent Jamie

Quality stuff, keep 'em coming.

Slippydiff said:

JamieG said:

Evening Henry, another cracking thread about your fabulous car. Glad to hear you have been out enjoying the brute. Please keep these threads coming! (PS - think I missed my chance with your old Manthey-car )

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Email sent Jamie

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Thanks Henry - reply sent

Great work again and especially on the front canister location. I was racking my brains as I read the post, questioning where I'd put them?
Great solution, especially with the protection offered by the arch liners. :thumb:

Rear Brakes

And so on to the brakes ...

There were several very specific briefs for the brakes. But first a quick overview of the existing brake set up :

The car was fitted with Mk2 six pots on the front with Alcon floating discs, and Alcon 350mm rear discs utilising the standard rear calipers spaced out with bespoke 10mm spacers. Both sets of Alcon discs were within their wear limits (the rears only just) but had had a hard life and the rears were badly Mick Jagger'ed





I asked the previous short term owner to remove the Endless front pads, as whilst their stopping abilities were beyond compare, they squealed like a London bus, something Mark is finding intolerable with the RS29's in his car currently. I concur that I find the noise equally unacceptable.

In place of the Endless pads went a set of completely shot, 70% worn Pagid RS29's.

Some of you will know that high performance brake pads used repeatedly on track and subjected to frequent high temperature heat cycling, causes the various elements of the lining to be burnt off and/or them changing in their composition accordingly.

The end result of this process is a large drop in the lining's coefficient of friction, this in turn leads to a wooden feeling brake pedal that lacks any real bite and this in turn increases disc temperatures and wear.
RS 29's have gained a reputation for losing their efficiency once 60-70% worn

The rear pads were standard OE Textar items that were 75% worn and again, well past their best ...

And so the the brief.
This is a fast road car, so the likes of the track biased discs from companies such as Alcon, Performance Friction or Brembo weren't even considered.
I wanted drilled rather than grooved or hooked disc faces.

The pads needed to be OE spec, easy to bed in, to work from cold, but work consistently at higher temperatures also. They'd also need to be OE from a NVH perspective, so no squealing, no vibration, no excessive noise under heavy braking from high speeds.

On the basis the engine now produces 465hp and the car weighs in at 1450kgs ?? I figured that Gen 1 997 Turbo (480+ hp, waaaay more torque and a kerb weight probably closer to 1750kg) brake components should be more than equal to the task.

The easy option would have been to fit a set of OE spec 350mm steel 'boat anchors" both front and rear, and that's what I went with for the rear discs. For the fronts I went for a somewhat more bespoke set up.

Rear Brakes.

A set of Sebro (they're an OE supplier) 997 Turbo 350mm rear discs were purchased (£89 plus vat each) along with a set of Textar 996 GT3/997 C2S front pads (they're the same pad profile as the 996 GT3/Turbo rear pads)

With the car up on stands for the now completed suspension fettling, I figured the rear disc and pad replacement would be a maximum of half an hour a side ... Fat chance :floor:

With the pads removed and the handbrake shoe adjusters backed off, the old Alcon discs came off to reveal the handbrake shoes on the O/S almost worn down to their backplates ... :?:

Matt had removed the rear calipers and discs to Timesert the rear caliper mounting bolts. This was necessary as some bright spark had used the original rear caliper mounting bolts, despite having fitted 10mm spacers to the caliper mounts, this left precious little thread for the bolts to screw into, and thus the remaining thread was overstressed and s t r e t c h e d.

At the same time as the threads were Timeserted, the handbrake shoe retaining/hold down springs were replaced (the new retaining springs can be seen in the image) as they'd failed and were allowing the shoes to cant over (and as a result bind) instead of running parallel to the handbrake drum surface :



And these are the same shoes less than 200 miles later (this the good end of the shoe, the lining on the other end was a wafer thin sliver) :



:wtf:

A quick call to Porsche confirmed I wouldn't be buying OE replacement set of shoes of them !! So thoughts turned to having the shoes re-lined, but before doing so, I thought it would be worthwhile giving the company I'd bought the rear discs along with the front and rear pads off, a ring for a price. Just as well, they supplied a set of four Mintex shoes for the princely sum of £25 plus VAT. ance-Tap:

With the shoes purchased I attempted to fit them. Let me say here and now, the handbrake linkage assemblies are fiendishly fiddly items (they're used on the 968, 964, 993, 996, 997, 986 etc) and despite having taken several images prior to stripping them down, rebuilding them wasn't a straightforward undertaking.

Having pulled the N/S apart and cleaned, inspected, lubricated and reassembled it, I thought the O/S would be a breeze ... :roll:



Having started to strip it down, I found that the pivot pin (blue arrow) was partially seized. As was the handbrake cable attachment pin (yellow arrow)

This pin floats freely (and is only about 8 mm long) and is retained/held captive by the sides of the stirrup (white arrow) but worse still the lever (black arrow) it runs in was fouling and binding inside the stirrup that retains the pin.

With it freed off and stripped down I set about tweaking the pressed steel stirrup to allow some additional clearance for the lever and the pivot pin that runs within it.

The stirrup is 2-3mm thick piece of mild steel that had been stamped into the required shape then folded and spot welded (red arrow) to hold the ends together.

Simple I thought, install a couple of small pry bars between the two sides, and then I'll spread them sufficiently to clear the lever that runs between them.

A quick 'pry" revealed the lever was tougher than it looked ... So on the basis brute force and ignorance can shift anything, I pryed (is that even a word ?) somewhat harder. At which point the tiny (2mm) spot weld failed.
This was the culmination of long, drawn out, irritating (nee downright annoying) and frustrating day :gunfire:

Tools became airborne, as did the broken stirrup. Meanwhile the neighbours most likely thought the bloke next door had a bad case of Tourette's .... :grin:

I shut the garage door behind me and kicked the cat before downing a large glass of Amaretto.

The following morning I took the broken stirrup to my local fabricator/welding guy. Five minutes of filing/grinding prep, followed by 2 minutes TiG welding and a further two minutes on the grinder and the strirrup was now worthy of being considered a MotorSport heavy duty uprated part.

Back home for 9am, the O/S shoes and linkage were reassembled and back on the car within twenty minutes.

(Tip : Snap-On make a superb tool that enables you to easily press these springs in and then rotate them 90 degrees to secure them, but a pair of thin-nosed Vise-Grips do the same job perfectly, although the pointy bits really dig into your palm when you use them in this manner) :



The new brake disc was degreased and offered up, but wouldn't fit over the new and freshly assembled shoes and linkage ... :splat:

Some head scratching and disassembly of the shoes and the linkage, revealed the linkage was 'too long" thus forcing the shoes apart sufficiently to stop the disc going over them. This despite the shoe adjusters being fully backed off.

Further investigation/analysis of the linkage showed it's fulcrum point was making its effective length too long, with no obvious way of shifting the fulcrum to decrease its effective length.

If all else fails, go on Youtube, and it was here the answer was to be found in the shape of a DIY video on adjustment of the handbrake ...

Prior to adjusting the handbrake shoes within the drums themselves, the handbrake adjustment itself needs to be backed right off.
With the majority of the screws retaining the centre console removed ... I happened across the one that secures the glovebox/cubby hole floor panel, and with it and the floor removed, the handbrake adjuster mechanism was revealed in all it's misadjusted glory :



:roll:

With the locknut undone and the adjuster nut backed off, the rear disc flew over the newly fitted shoes :thumb:



The handbrake shoes were adjusted at the hubs and the handbrake lever subsequently adjusted in the cabin.

Sorting that lot out took considerably longer than the hour it should have done to fit new rear discs and pads ... and had the handbrake shoe linkages been checked when the retaining springs were replaced, along with the handbrake shoes and lever itself being adjusted correctly, would have been completely unnecessary...

Considering it's old tech, the Porsche handbrake system is a pain to get set up correctly. I've been through this with both my 996 and 944, both the same set up and both equally annoying.

My 944 had been plagued with handbrake MOT fails and advisories over the last decade with previous owners and their mechanics, it took me some thinking and time to actually get it sorted for the first time in a long time, both cars work a treat now but as you found out there is a procedure to follow to get it working well and not binding.

I have used Mintex shoes on mine and there is also significantly more pad material, in length than the shoes that were removed.

infrasilver said:

Considering it's old tech, the Porsche handbrake system is a pain to get set up correctly. I've been through this with both my 996 and 944, both the same set up and both equally annoying.

My 944 had been plagued with handbrake MOT fails and advisories over the last decade with previous owners and their mechanics, it took me some thinking and time to actually get it sorted for the first time in a long time, both cars work a treat now but as you found out there is a procedure to follow to get it working well and not binding.

I have used Mintex shoes on mine and there is also significantly more pad material, in length than the shoes that were removed.

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Agreed. It's positively "Dickensian", but not helped by what are clearly lazy technicians not being bothered to delve into its intricacies or seemingly adjust it properly/at all.
Once stripped, freed off, lubricated and reassembled correctly AND adjusted properly, it's "functional" if not particularly pleasant to use.

I noted the increased lining length, it almost had me scuttling to the phone to question the supplier as to whether he'd supplied the correct part. But a back to back comparison showed the backplates were all but identical.

Good effort Slippydiff, I think we all have those simple tasks that turn into epics. In the early days it was usually caused by not having the correct tools. These days one is always looking for a new fabulous tool to add to the collection (I bought one of these [below] rotator ratchets recently on recommendation - ideal for tight spots where you cannot lever the ratchet)

To be honest though I am surprised the shoes are so badly worn. I rarely if ever use the handbrake going on the Norway premise where in Arctic you never put the handbrake on as it is likely to freeze to the discs. I always leave in gear and only use it after a track session to keep off the main brakes or on a hill start.

Trouble is with these post is you think "Hmmm .....perhaps I should put new pads on just in case"

Looking forward to the next episode.

Pip

Pip1968 said:

Good effort Slippydiff, I think we all have those simple tasks that turn into epics. In the early days it was usually caused by not having the correct tools. These days one is always looking for a new fabulous tool to add to the collection (I bought one of these [below] rotator ratchets recently on recommendation - ideal for tight spots where you cannot lever the ratchet)

To be honest though I am surprised the shoes are so badly worn. I rarely if ever use the handbrake going on the Norway premise where in Arctic you never put the handbrake on as it is likely to freeze to the discs. I always leave in gear and only use it after a track session to keep off the main brakes or on a hill start.

Trouble is with these post is you think "Hmmm .....perhaps I should put new pads on just in case"

Looking forward to the next episode.

Pip

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Hi Peter, I'm like you when it comes to handbrakes, I rarely if ever use the things.
The N/S handbrake shoes would have gone again inside the new discs, though the O/S definitely wouldn't.

Put simply, the accelerated, excess wear (less than 200 miles since the shoe retaining springs were replaced and the shoes adjusted) was due to the two pivots (the cable attachment pivot pin AND the pivot pin of the activation lever) being seized or partially seized, along with the activation lever getting jammed in the stirrup due to a lack of clearance.

In addition to the above, which would have made adjusting the shoe to drum clearance accurately all but impossible, the adjuster on the end of the handbrake cable/s at the handbrake lever, hadn't been backed off at all, and by not not doing so, trying to adjust the shoe at the hub was a pointless and expensive exercise in futility.

Front brakes.

Fortunately the car was fitted with the Mk2 6 pot front calipers, and whilst they were in reasonable condition aesthetically, I thought it best they went away for a purely mechanical refurb.

I mentioned in a previous post, that whilst removing the front dampers, I'd made a faux pas, that being that whilst I was manhandling the the N/S strut out of the hub carrier/upright, the caliper which I'd carefully balanced out of the way, fell off it's temporary perch, in doing so the full weight of the caliper was born by the braided hydraulic brake line. It may have been undamaged and unstressed, but knowing it had happened meant I now had to replace it, and whilst doing the N/S, I may as well also replace the O/S.

With both calipers removed from the car, I inspected the dust seals, all twelve had disintegrated and were in need of replacement and several of the ceramic pucks had separated from the ends of their pistons too.

I rang a couple of Brembo agents to get the prices for the primary piston seals and the dust seals (and the cost of replacement pistons with their ceramic pucks) The figures were truly eye watering.

So I decided to take the calipers over to Bigg Red at Worcester to be mechanically refurbished.

My first question to them was : Are the replacement seals they supply genuine Brembo items ?

They informed they were not, they were manufactured by a well regarded Spanish company who supplied seals to a host of automotive suppliers and brake component manufacturers.

Bearing in mind the good reviews Bigg Red seem to get and the volume of calipers being overhauled in their workshops, they must be doing something right. So despite concerns over the non OE seals being used, I elected to get them to do the refurbishment.

This would entail cleaning and stripping the calipers, fitting new primary seals, dust seals, bleed nipples and finally, pressure testing them ...

They had the calipers for three days, and their costs were very reasonable. Whilst delivering the calipers to them, I noted they also manufactured Hel braided brake lines. Accordingly I provided them with the braided line off the car and asked them to replicate a pair.

With the calipers now overhauled, I was left waiting for the AP front discs to be supplied and the custom bells to mount them to be manufactured.

I'd planned to fit 380mm X 34mm discs, but I suspect that clearance (even with the BBS E88's) would have been on the tight side. So I settled for 365mm X 34mm Audi B7 RS4 front discs. These are a standard AP Racing part (albeit they have 6-8 week lead time) :roll:

They're reasonably priced, but have the benefit of being supplied with the required mounting bobbins, securing nuts, bolts and washers and anti rattle springs included in the price. Two bobbin sets would be required and they'd normally cost £50 plus vat for each bobbin kit. Thus making the discs considerably cheaper.

https://www.part-box.com/ap-racing-...-side-audi-rs4-b7-rs6-c5-365x34mm-cp8080z14sd

These aren't much (if any) lighter than 362mm Alcons, but both are lighter than the OE one piece 350mm 'boat anchors".

The bells took some weeks to manufacture, but were worth the wait. They're as light as feather and nicely finished with a durable hard anodised process.





The slightly larger discs also required some slightly thicker 8mm caliper spacers, these were supplied with the bells.
To ensure the front pads were easily bedded, quiet and worked from cold, but also up to the rigours that would be imposed upon them, I went with a set of TRW 997 Turbo items.

I did a dry build, but needn't have bothered, the whole lot bolted up easily and fitted absolutely perfectly :thumbs:

Fitting the new Hel braided brake lines wasn't so straightforward ...
When I came to fit them to the car, the diameter of the bosses on the chassis end of the pipes were too large to fit the brackets that secure the connection between the hard line and the flexi pipe on the inner flitch.
Of course I could just have opened out the hole in the brackets, but that was never going to happen. So I returned the pipes and Bigg Red credited me in full.

I asked if they could supply them with bosses that were the correct diameter. They said they'd have to speak to the manufacturer in Germany, but they rang me a day later to say Hel couldn't supply the correct fittings to enable them to manufacture the pipe.
I suspect they could, but they would probably have to have bought a box of 100, and they didn't want a box of 96 of them sitting on the shelf for the next ten years ...

Next stop James Lister Motorsport in West Bromwich. They manufactured a set of braided hoses that fitted perfectly, though their hose ends didn't have a flange formed adjacent to the hexagonal part of the boss (to stop the pipe pulling through the bracket on the inner flitch) ...

This was easily addressed by getting a mate to machine me a couple of chunky washers that fitted tightly over the circular boss, but not the hexagonal section.
The braided hoses cost the princely sum of £18 plus vat for the two ... The washers were FOC.

With the discs and calipers fitted and plumbed, I tried to bleed the brakes (and let me state for the record, I HATE brake fluid, and I HATE working with brake fluid even more !!) I always have, and always will. Horrible slimy stuff that gets everywhere, and is difficult to shift when spilt in large quantities ...

I don't mind bleeding brakes on my own, though the bleed pipes I use are effective (they're just plastic pipes with one way valves on their ends) they're old and the rubber ends tend to slip off the bleed nipples on the calipers, and when they do so, they spray brake fluid everywhere. Hence my hate of the infernal stuff.

I've learnt to secure the rubber ends of the hoses to the bleed nipples with small cable ties, but it makes the job I hate doing already, more time consuming and more of a PITA !!

So with my magic bleed kit fitted to both nipples on both front calipers, and the M/C reservoir full of Motul RBF 660, I pumped the pedal to get the fluid through (not forgetting the front calipers had been off the car two months and the fluid had long since dripped out of the pipework)

Try as I might, I couldn't get a pedal of any sort. A check of the N/S/F caliper revealed a large pool of brake fluid on the floor beneath it ...
I double checked the hose connections, then the bleed nipples (I only back them off ½ to ¾ of a turn to reduce the chances of air getting back into them), all looked fine, so I cleaned the caliper with brake cleaning fluid and tried again.
Same result ...

This required further, close examination, and with the pads removed, it became clear the leak was coming from one of the pistons/seals, witnessed by a small stream of brake fluid running in a tiny, neat, barely visible stream from the piston's dust seal.

Bigg Red had told me they pressure test all their rebuilt calipers, so to find a caliper leaking in this manner was 'unexpected" to put it mildly, not too mention less than confidence inspiring ...

A call to them saw them agree to collect the leaking caliper from my house that evening. And sure enough the boss (Phil ?) appeared to collect it.

I asked if I could have the caliper back the following day. To which he replied yes, but I'd have to collect it as he was going to a funeral. He suggested I ring them mid- morning to see what the problem was and when the caliper would be ready for collection.

Sure enough I rang Bigg Red at 10am the following morning to see what progress had been made. Seemingly no one knew anything about this leaking caliper .... Hmmm :?:

I explained the situation to them, and was promised they'd ring me back within the hour to give me an update. Fair play to them, they rang back half an hour later and said they were pressure testing the caliper now, and that it would be ready for collection by lunctime.

I duly collected it and was informed that they'd found a faulty seal which they'd now replaced and pressure tested. I fitted the caliper to the car and bled the system without any further problems.

I have mixed emotions about Bigg Red, primarily because I can't see how a seal fails between a caliper being rebuilt and being pressure tested and the caliper being fitted to the car some 3-4 weeks later ? The cynic in me says it wasn't pressure tested after being rebuilt and I dislike being lied to, least of all about such a safety critical component.

The whole episode left me lacking confidence in their ability to overhaul what is a critical part of the car's braking system.
No matter, here's the end result of my labours :





I'm very pleased with the outcome of the brake system overhaul/replacement and my impressions of these (and all the work I've carried out to the car) will follow once I've completed my reports on tweaking the cooling system and sorting the car's bodywork

I have used Bigg Red seals on most of my cars that I have kept for any length of time and are currently in both my Porsche's, I have found their parts to always be a perfect fit but I have only ever fitted them myself, I have a thing about other people working on my cars as I don't trust that work is always up to my care, I'm not on the clock when I do my own work.

infrasilver said:

I have used Bigg Red seals on most of my cars that I have kept for any length of time and are currently in both my Porsche's, I have found their parts to always be a perfect fit but I have only ever fitted them myself, I have a thing about other people working on my cars as I don't trust that work is always up to my care, I'm not on the clock when I do my own work.

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Yep, I'm with you on that , though I'd hoped (expected) that by handing the job to BR I'd ensure it was done right, with the added benefit that the end result would be pressure tested. My unease over them (and their abilities) stems from the fact the caliper miraculously 'sprung a leak" between their alleged pressure testing of the finished job and then it sitting on the shelf in my garage for a few weeks before failing once bolted on to the car ...
If they didn't pressure test it (and I don't think they did) what other safety critical processes have been omitted/forgotten or ignored ?

Hi Henry,

Enjoying reading the ups & downs of your time with the car. Is this being written in real time, or are you still catching up?

Cheers

Ollie

-ollie- said:

Hi Henry,

Enjoying reading the ups & downs of your time with the car. Is this being written in real time, or are you still catching up?

Cheers

Ollie

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Hi Ollie, I hope you're well? I was on your doorstep on Monday lunchtime (though I was in the 'wrong" car)
Fettling halted for the summer about a month ago, just enjoying it when work allows now.
I'll let you know in advance when I'm going to be in your neck of the woods with car next It'd be good to catch up.

Still waiting for pictures of the car with the new wheels on ...

Slippydiff said:

-ollie- said:

Hi Henry,

Enjoying reading the ups & downs of your time with the car. Is this being written in real time, or are you still catching up?

Cheers

Ollie

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Hi Ollie, I hope you're well? I was on your doorstep on Monday lunchtime (though I was in the 'wrong" car)
Fettling halted for the summer about a month ago, just enjoying it when work allows now.
I'll let you know in advance when I'm going to be in your neck of the woods with car next It'd be good to catch up.

Still waiting for pictures of the car with the new wheels on ...

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Really well thanks! Trust you are too.

Nice, it's fun to read about you & several others getting involved in the mechanical work yourselves, and especially then taking the time to document it on here. I was used (being a BMW nerd historically) to seeing & enjoying that kind of content, but being new to the Porsche scene it had appeared to be lacking, until recently 8)

Wheels are yet to be fitted. FVD have sent RS rears, so short of fitting some GT3 R style overfenders, I'll need to wait until the suitably sized replacements arrive.

Do let me know next time your local, would be good to go for a beer and I'd love to see the Zanzi cup.

Cheers

Ollie