Sincere congratulations from a long-time lurker. Your build has been both educational and inspirational. Thank you for documenting your journey - - I've learned a lot and am applying it to some projects of my own. It's been a truly epic thread.

I'm thrilled you're driving your dream. Best wishes for continued success.

PS: Your mileage looks good to me. I'm lucky to see 12 US mpg in my Cayenne TT, and my 997 [non factory] turbo is mid-teens at best. That said, I've got a thing for the boost... Cheers!

Thanks Brainz! Much appreciated.

Yeah I can't wait to now put some miles in - such a good car to drive long distance, I was less tired after a 340 mile round trip on Saturday than I usually am doing that distance in the BMW, even with the nervous tension.

I re-looked at my mileage calculations - I guess my brain had gone to sleep at that point - I'd converted the wrong way....now avg of 15.4mpg (US)...still more economical than your Cayenne TT though!! Some nice toys in the stable!

Cheers
Spencer.

Another update - spent yesterday messing about and swapping over the engine mounts. I still had the original ones in one of my many boxes of parts, a quick clean and they look like new and weren't too problematic to fit. Whilst the RS ones are great for stability, at the moment I'd rather remove the vibration (although I am getting used to it), so it'll be interesting to see how much difference they make.

I've also decided - while I'm at it - to remove the headers and buy some more sealing rings. Everything's a lot easier with the bumper removed, so that will come off tomorrow evening now that the car is back in the air with wheels removed. The silencer can then easily be removed and if I do need to separate the turbo from the 1-2-3 half of the headers, then again, it's a lot easier to disconnect the hoses running to it. I've also got EGT and backpressure sensors hooked up the secondaries, so getting access to these needs the bumper removing.

I'm currently trying to clarify the different header sealing rings that are available; two part numbers in the PET for a 964 (993 111 195 00 and 930 111 233 00). The illustrations I've found so far imply that the ones that work best, as recommended on Saturday, are the Carrera items rather than the 930 part numbered Turbo items. Whether or not they're interchangeable (I don't know the Carrera exhaust port diameter), is the bit I'm seeking clarification on, before ordering £70-80 for a set of 6 genuine items.

The hardware I need for the case perimeter nuts and 2 missing bolts is on order, plus another pair of Supra clamps for the silencer tail pipes....damn things galled on me. Originally I ordered full stainless, which was a mistake, should've ordered part stainless (band) with BZP plated bolt. Live'n'learn.

Think I'll fit the new dampers and springs - have got 8 weeks until Le Mans...I think even I can get those installed and setup in that time! (maybe).

Thinking about this while I'm typing it....I'm not convinced that the 930 part number won't work - what I think may be the problem is that the less-than-stellar headers I have (although they're spot-on dimensionally) may be the issue. When building the engine, I did carefully measure the protrusion of the primary "stub" that extends through the flange. Comparing that to the depth of the step in the heads, and adding the thickness of the sealing ring, should be sufficient, i.e., the step was shallower than the stub + ring. So, my theory is that the end of the stub is not parallel with the mating flange, in other words, I'm not getting a 360º seal against the ring.

The easiest way I can think to do this would be using a depth gauge in, say, 4 positions on each primary stub to verify (12, 3, 6, 9 o'clock). The other way would be to turn a jig on the lathe, which would hold a DTI close to the way of the stub...rotate the jig on the stub, and the DTI will give a clock reading around the circumference....hmmmm....yup, think I may make that once I've removed the headers.

Then I've got to go about correcting any variation. That'll be "fun" (tedious)

Bloody hell, full of good ideas this evening...

Even easier way of checking and correcting....I'll turn a stainless ring that slips over the protruding stub.

- The ID of the ring will be a clearance fit of the OD of the primary stub.

- The thickness of the ring will be whatever the head step depth is, minus almost the sealing ring thickness (leaving a ittle bit, for nipping-up).

- The wall thickness will be something that allows me to get a file nice and perpendicular to the stub.

And this will very quickly show whether or not the stubs are parallel to the flanges.

And on that last flash of brilliance for the evening, I'm going to bed.

Spencer I think you want "distorted thread" M8 lock nuts for the case perimeter. Rather than DIN 985 Nylocks, because the nylon can melt and leave you with no locking. In the later cases the Factory specified such a nut, I haven't checked PET but I'm pretty sure.

Here is what they look like:

https://encrypted-tbn1.gstatic.com/i...k4Al9WypwQXKPQ

Now, the torque settings are useless with this type of a nut, becuase the friction from the locking feature will make the wrench click long before the requisite preload has been obtained. So measure with a stretch gauge -use a conventional DIN 934 plain nut with the same washer, bring to fastener to clamp load until the torque wrench clicks then measure the length between the back of the flange and the head of the stud with a micrometer, then install the lock nut and turn it until the same stretch is achieved.

Or just tighten it with a wrench by hand until it feels tight and call it cool. :)

^^^ agreed, those are the preferred fastener.

However, as nylon melts at approx. 220C/428F... If you have the nylon melt in the perimeter case fasteners, I'd venture to say you have much, much bigger problems on your hands -- problems requiring a fire extinguisher!

Yup, a set of those nuts were ordered yesterday John - was rather hoping they'd be with me today, but no.

I found out that they're called Stover Nuts...and now I'm typing it, I wonder whether I have a box of Wurth ones stashed somewhere. That'll be annoying, if so.

I have a stretch gauge in the toolbox - bought it to tighten the rod bolts....however, I'll pose a question. Would the tightening spec already accommodate the increase in friction of a stove nut? If the factory specify this nut, and they give a specific dry tightening torque, would it be expected to use either a stretch gauge or a vernier to in order to reassemble the crankcase?

Of course, using the stretch method on 4/5/6 studs and finding the mean stretch vs factory torque, and then finding the stove nut torque to achieve the same stretch, should achieve the same result....but as you say, using The Force with "click + a bit" is probably fine, lol!

Lol....don't!....There's one there that I really really don't want to test!

I've got the bumper off, well worth spending less than an hour to get it removed, access is an order of magnetude easier.

It's also been a good exercise to perform an inspection of the components. A couple of points I've picked up...

1) Despite adding the various heat control measures, like the gold foil and Nimbus sheet metal shields, there's obviously significant heat travelling upwards...the rubber lined P-clips that hold the Lambda sensor harness in place on the top side of the engine tinware, are shot - the rubber completely burnt and crumbled.

2) At the time, it looked like a good idea to retain the Lambda harness in place; saves it getting caught, or dropping somewhere where it shouldn't. In retrospect, this makes it completely unserviceable should the Lambda fail. It's a bumper-off job to change it - that's no good, so I'll re-route it in a simpler way before reassembling everything.

3) I found a loose bolt on the silencer hanging bracket - needs split washers under the heads.

4) A few of the bumper fastener screws, that engage into the speed fasteners, have vibrated a little looser than I'd want. I'll fit new speed fasteners, clearly the original ones have lost their strength to hold tension against the screw.

5) Have now found an ideal route to thread the oil:air separator tank drain hose. It will now run down under the AC pump, where there's a spare rubber grommet in the tinware. From there, I can fasten it to one of the major engein oil lines, right up to the -8AN fitting that the turbo oil feeds into the drip tank. Perfect.

6) I may replace a lot of the thermal sleeving I've used on the various hoses that run near to the turbo and the silencer. I used the aluminised cloth sewn sleeves, but the extremes of heat have destroyed the reflective aluminium already. The material itself it holding up fine, if a little scruffy. Perhaps it's time to switch these sleeves for the orange silicon type. Doesn't look as nice, IMO, but it's about function not form.

I have to say that upon inspecting the components at the rear end, I'm stunned just how much heat has clearly been generated; lots of evidence of it, and I've only done 450 miles in total! In fairness, there's been an unnatural amount of idling whilst we've been tweaking the maps, so lots of static hot air, but even so...

Right, the night shift is about to start, no rest for the wicked.

Some pics from last nights night-shift. A good, productive couple of hours....

The nuked p-clips debris....

http://img.photobucket.com/albums/v2...3CD8E4A55D.jpg

These fasteners will also now be replaced with stainless items; the area was quite wet, some of the fixings already rusted.

Removal of the bumper and heat shields paying dividends; all the areas behind the shields look to be in fine fettle.

http://img.photobucket.com/albums/v2...FBB263ADE4.jpg

Access to the turbos supporting bracket fixing is now very easy (hoping to keep the turbo attached to the manifold for removal)

http://img.photobucket.com/albums/v2...C092EA5618.jpg

When originally fitting the oil feed hose to the turbo, I just about got by with the OE 9/16" spanner in my toolbox, but the width of the jaws allowed approximate 0.8659º of rotation before fouling the compressor housing. To remedy that, and in the same spirit of up-cycling my Grandads tools, I found one of his old offset ring spanners; brings the swinging height to the point of almost clearing the turbo housing and with the bi-hex ring, I can now really snug this hose fastening up nicely....

http://img.photobucket.com/albums/v2...FBAD2E4352.jpg

http://img.photobucket.com/albums/v2...17C2AC716F.jpg

So, not a million miles away now - just need to uncouple the heat take-off pipework and then start swearing at the 12 locknuts on the header flanges, then removing the system...definitely a two-man job with the turbo still attached.

What is the small AN fitting for on the exhaust just before the turbo flange?

Sent from my Nexus 6 using Tapatalk

It's one of the exhaust gas back-pressure connections, one on each secondary before the flange. They join onto stainless pipes that are about 50cm long before then interfacing to -3AN hoses, then into pressure sensors.

As it happens we've not been able to use them yet. Lots of work to install but we don't have a suitable map in the ECU to present the readings. Work for another day ($$$'s)

Also on the secondaries are 2x exhaust gas temp sensors that feed into a 4 channel AEM system, which then feeds into the ecu. That is up and running, and is useful info to see.

....another long time lurker here.
Love your work Spencer, very inspiring.

That type of nut is also known as a Cleeve Lock Nut or Prevailing Torque Nut.

Hi Costa, thank you, appreciated!

Got it. I figured it was some sort of measurement port (or perhaps even antilag injection). I'm familiar with EGTs for turbo applications, but not familiar with how exhaust back pressure is factored into the ecu map. More to learn.

Sent from my Nexus 6 using Tapatalk

I can't believe how long this has taken, it's not a case of just getting the bumper off, there's so much else that needs to be removed, whole back-end of the car is in pieces, it seems. Talk about soul destroying, but there you go, it's necessary just to get to everything.

http://img.photobucket.com/albums/v2...F210D24637.jpg

Headers are finally now off, with the turbo still attached. A lot of the top-of-engine stuff has had to come back out yet again, just to get to the EGT sensor plug/socket....cunningly mounted under the inlet tract :rolleyes:

While it's all in pieces, now's the time to send the cold pipe out for powder coating. I've opened up the BOV as well, to see what spring is installed. After speaking with Chris a few weeks ago I may increase this spring rate, as it does open very easily when lifting.

Looking at the headers and re-familiarising myself with how they seal, the blowing is quite obvious....

#6 - Not too bad, no evidence of soot on flange
http://img.photobucket.com/albums/v2...7D3ED487FB.jpg

#5 - Needs fixing
http://img.photobucket.com/albums/v2...4916221649.jpg

#4 - Not too bad, flange dirty but not sure yet if it's breaching gas.
http://img.photobucket.com/albums/v2...638BB7037C.jpg

#3 - Not too bad
http://img.photobucket.com/albums/v2...FDF1904AB5.jpg

#2 - Not too bad
http://img.photobucket.com/albums/v2...3379E9AD51.jpg

#1 - Worst of the lot, needs fixing
http://img.photobucket.com/albums/v2...7E33A779A5.jpg


The first job will be to check how flat the flanges are; simple to check, a pain in the arse to rectify if required, with the primaries protruding through. I'll get the vernier out again and re-check the step depth in the exhaust ports.

While a lot of the top-side components are out of the way, I'll likely get the old dampers removed and fit the new ones. Getting to the 3x top mount fixings at each corner is impossible with everything installed. To that end, all the required components have been ordered from Porsche, so hopefully it'll be a straightforward swap in a week or two's time (and I get to use my torque multiplier again to undo the M14 lower damper bolts...."should be a breeze").

Just some light duties this evening to report on.

A check with a (new) steel rule against each of the header flanges shows that they are indeed flat. Thank God. Checked in the 4 planes on each of the "diamond" surfaces.

Here's some corresponding pics of the ones from yesterdays sooty header photos:

1-2-3....

http://img.photobucket.com/albums/v2...BE61CA5F52.jpg


4-5-6...

http://img.photobucket.com/albums/v2...B02A17A694.jpg

Look like hell, don't they? Annoying, but it justifies pulling everything to pieces I guess.

What's also annoying is that when I was casually peering down the intake elbow for the turbo, I saw this...

http://img.photobucket.com/albums/v2...B5A4F30354.jpg

I'm bloody plagued by oil issues. A quick shove of finger down the silicon elbow that accommodates the oil:air separator tank from the main oil tank, and it's dry. The end of the inlet tract (that enters into the turbo elbow) and there's signs of oil.

So, the only other place it can be coming from, is from the (long) breather hose that comes up from the turbo drip tank, through the tinware and across to underneath the inlet tract, joining half way along.

I confess to be a little puzzled when I removed the drip tank yesterday, as to how much oil drained out. It wasn't gushing out, but neither was it only a few drips. For once I had the forethought to grab a container before trusting the tank was empty and undoing the connection...

http://img.photobucket.com/albums/v2...C87A4B58_5.jpg

And when you compare that the size of the tank and its outlet...

http://img.photobucket.com/albums/v2...B4A9BB1E_1.jpg

Maybe this is normal, but my expectation was that because the oil feed into the GT35R has been restricted (versus the way the K27's journal bearing is flood-fed), that the auxiliary pump would have no problem keeping pace, leaving the tank empty at all times. In fact, I had considered whether the pump would be sucking air because of the lesser quantity of oil.

Now I'm wondering whether the aux pump is actually working correctly. I guess a check would be to use a short length of clear tubing in between the swaged hose and the oil tank entry, and observe the oil flow.

Or maybe that's a complete red-herring, the drip tank and Aux pump are fine, but the induction is sucking up the oil from the tank.

Or maybe the oil in the turbo is perhaps a turbo seal that's gone? (find that hard to believe, as there's evidence of oil upstream in the inlet tract, but welcome any educated thoughts)

A few other jobs this evening; the headlights are now removed and stripped again. The powder coating on the rings is too thick, preventing the body coloured trim ring from clipping into place. The plan for these is to get them blasted back at the powder coating shop where they were done (shame, they look really nice) and either get them re-done but as a very thin coating, if they do such a thing. More likely is that I'll get them plated. New ones are stupid money, so worth giving this a shot first.

The cold exit pipe from the IC is also now prepared for sending to be powder coated. Final checks made with IC alignment following the switching of the engine mounts last weekend, just to make sure nothing's moved, and that the lid still clears the IC - it does, thankfully.

^^^^^
"Maybe this is normal, but my expectation was that because the oil feed into the GT35R has been restricted (versus the way the K27's journal bearing is flood-fed), that the auxiliary pump would have no problem keeping pace, leaving the tank empty at all times. In fact, I had considered whether the pump would be sucking air because of the lesser quantity of oil.

Now I'm wondering whether the aux pump is actually working correctly. I guess a check would be to use a short length of clear tubing in between the swaged hose and the oil tank entry, and observe the oil flow."

Or, you may have an air leak between the suction end of the turbo sump pump and the turbo sump tank.