944S2 16V Turbo Build

[BasHenneman]

Well I've had some good news for once, we found a welder who specialises in exotic alloys who is confident he will have some success repairing my cross over cracks. Apparently heat treating before welding is the key, if this works it will buy me some time to get the car running until I can get something fabricated.

New oil pickup arrived (not sure I needed it but its cheap insurance) The sump is finally on and timing/balance belts all done. It took a little while to get our heads around timing the 968 cams but we got there in the end.
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Rebuilt intermediate steering shaft arrived from JMG in the UK, added a little heat protection because these sit about 10mm from the headers in the RHD car. I didnt realise how much play mine had until the new one arrived.
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Nice work Luke! Happy to see some progress again!
Really digging that CF cover plate! Do you have the step file of it? It would go really well with my CF intake!

[Bergerac]

No STL Bas, it's hand made.

Did a bit of zinc plating today, it's not perfect but it's came out surprisingly good. Only a few pieces had to be redone.

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[Bergerac]

Getting close now

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I had to employ a unique strategy to mount the turbo temp switch. Its not vital to have this switch as my pump is controlled by the ECU not the stock relay but knowing when the turbo is sufficiently cool after a run can only be a good thing.

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[Thom]

Even if there are occasions when the fans keep running for a short while after the engine is turned off the turbo's CHRA will keep radiating heat that only coolant can absorb and circulate, thus the need IMO to keep this function enabled. At least this has been my experience with either of the 3 engines I have had in my car, especially if the car is parked under the sun. I am not sure how you control this with the ECU if it is turned off.

Did you have the TTV flywheel lightened eventually? If not you better do it now as it is as heavy as the stock flywheel and will make for S-L-O-W gearchanges as I have experienced, not a desirable feature IMO with the response of a 16VT engine, unless perhaps for events like quarter mile racing. From what I can remember of early full load drives after breaking the engine in, and that was still with the mega restrictive stock intercooler, a stock weight flywheel should make for far worse wheelspin than what I get now and may cause some traction control to kick in pretty much all the time, not something I'd wish if a "natural" balance between the engine and chassis should be retained, and I mean with as little driving aids as possible. A stock weight flywheel makes sense on an 8V where we want to shoot for as much mid range beef as possible, but not so much on a 16V which is all about top end breathing and fast gear changes, IMO at least.

Great work anyway, looking forward to hearing of the first start up.

[Bergerac]

The ECU has a power hold function, you use one of the outputs to hold the ECU relay in, or in my case the PDM powered up which the runs fans and pump. Its on a timer ATM, but I have some ideas about how I can setup it up to stay on as long as required with some logic and virtual outputs.

How much weight did you manage to take off? the KEP pressure plate weights a ton so Im not sure how much difference its going to make?

[Thom]

-1.5 kg if I remember right, which with a KEP2 made a massive difference for me. Just wanted to somewhat warn you before you have everything buttoned up and figure out, possibly after spending further time on teething issues and on the tune, that the overall experience is eventually let down by excessive inertia in the rotating assembly. Out of the box the TTV flywheel may have the same mass as the stock flywheel but it is a rather crude design with a more or less uniform weight distribution over its radius and will cause more inertia than a stock flywheel. My machine shop had lightened both my former stock flywheel and my current TTV flywheel for me and although he got them down to the same final weight he found difficult to get inertia with the TTV flywheel down to the same level as the lightened stock flywheel, and I can feel this in the way the engine reacts to throttle inputs. I would say it's "just ok" by now.

With that said and depending on your experience and how you want your car to drive it may actually suit you fine. Here's just my real world feedback for you.

[Bergerac]

Bosch '200' fuel pump installed with stock sleeve and fuel lines finally finished. It seemed like none of the fittings were going to work but I just ran with it and everything lined up with the stock mounting plate. I've got to wonder what the hell Porsche were thinking with this design.

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I'm pretty happy with the way the routing for the front coolant line and charge line has played out, the silicone bend will be trimmed a bit but this should look nice and clean in the car.

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I installed some heat shielding to in the spots the S2 didn't have it compared to the turbo, I had to also replace the A/C line with one from a turbo, the stock one was going to clash with the compressor housing

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Transaxle with LSD installed is back and Only 944 short shifter added. Sean Buchanan said it one of the best condition boxes he'd seen for a while so only the diff bearings and a few seals were changed. Hoping it will hold up well but I managed to pick up a spare S2 AOS trans cheap just in case.

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Thanks Thom, I'll look into the flywheel, I was hoping to have the engine in this week but the crossover pipe and headers were held up again with the guy doing the coating ending up in hospital.

[Bergerac]

It's in!

TT and transaxle went in today too, apart from an exploding release bearing it's going fairly smoothly.

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[944m3]

Well if someone wants an intake, best get in touch with Sebastian or me than so you dont get a cast one but a CNC one for about the same price

Bas are you guys doing them all with a carbon plenum or are you mainly just selling the runners and flanges?

We’re now doing the first test and then making an Aluminum plenum so we can make the full intake.

Any update on the intake?

[BasHenneman]

Bas are you guys doing them all with a carbon plenum or are you mainly just selling the runners and flanges?

We’re now doing the first test and then making an Aluminum plenum so we can make the full intake.

Any update on the intake?

Yes! We now have a finished 8v unit and the 16v on my car is installed and making boost!
Send me a PM or email me if you want more info (I’m only on this forum to see Luke’s progress)
[email protected]