8 Nov 2009

Added the flex tube to the exhaust. It’s finishing other than muffler hangers which will happen later. Note the mocked-up rear wheel; due to the chassis sitting on the table, the wheels can’t sit at ride height, but it gives an idea how big they are ๐Ÿ˜‰

So now starts the long process of wiring the car. First up is placing the fusebox; placement is important for both weather weather reasons and being able to access it after the lights go out on a dark night! The first real wiring is the engine/ECU wiring, which goes behind the seat on the backside of the bulkhead. Shortening the harness was easy, though there’s some wires left over – who knows what they are. A paperwork task is adding a connector so the dash can be completely removed. Also made a list of missing connectors and the needed lengths of battery cables.

21 Oct 2009

The exhaust is almost finished and in hindsight it’s overdone – again. Thing is, what’s the point of doing something half-assed? It could have been a constant reminder of corners cut, so no corners were. How much better will it work than an ordinary turbo with a built-in wastegate? Who knows, but we’ll have an idea during the first tuning session and first drives. The tube at upper-left isn’t welded; it’ll be replaced with a flex-joint. It, along with the oil supply and oil return lines were ordered.

Still have to figure out a support for both the turbo and muffler. On Kimini, all the rubber muffler mounts did were to melt and smoke, so Midlana will get stainless supports. After that’s finished up, time for the electrical system!

Heard from my brother who said at the trackday weekend, by the end of the event he was laping faster than a Porsche GT3. That’s very impressive – those GT3s are serious track cars.

18 Oct 2009

After a very long day, the turbo manifold is done. Still left is adding the muffler tubing, along with the wastegate exit pipes. The exhaust tube in the turbo is just stuck in there for effect; it’ll be rerouted, but yeah, it’s pretty big. Made a list of all the bits and pieces needed to finish it up, included the oil system. An oil pressure and oil temperature sensor are needed, and will be plumbed into the remote oil filter housing, after figuring out which brand to buy.

I got some grief on a forum after posting how expensive the exhaust is. I could have used 304 weld-els which would have lasted for a while, but went with 321 to ensure longevity. Ask anyone who knows about turbo track cars and they’ll say to use cast-iron, 321, or Inconel to have it last, or risk it disintegrating or cracking. Whatโ€™s it worth having a trackday terminated by a cracked header? The wasted entry fee, gas to get to the track and back, food, lodging, it adds up. Around here, having that happen twice would pay for the 321 header.

Also, having the car break is a poor way to instill confidence in potential builders; what’s that worth? The goal is to built a high-powered example of what the car can> be, proving the chassis can handle it, and if builders choose, they can do the same; it gives them options. For example, using a stock drivetrain means they may be able to use the OEM exhaust manifold – which no one wants – for practically free. Maybe I’m looking at this wrong, maybe I should put on my Marketing Weasel hat and mislead people how cheap it is to build a turbo engine – “Joe Smith built his for $50, you can too.” I don’t think so.

12 Oct 2009

Sorry for the late update; yesterday was a long day. Pushed hard to get the entire manifold tacked up and got it done late in the evening; the pictures pretty much sum it up. A header is great fun to make – lots of room for creativity. The primaries are within about 1/4″ of each other, and for a turbo manifold I’m not going to sweat getting closer than that. While not intentional, the manifold somehow looks like it belongs on a drag boat…

The big concern – like always – is heat distortion. The worry is that as it’s finish-welded, the tube assemblies will move round enough to ruin the collector slip-joint alignment; all four tubes have to line up just right or the tubes will jam part-way on. Each tube assembly will be welded separately, polished, then welded to the cylinder head flange, giving one last chance to tweak alignment. Even then, as each tube is welded, the flange will distort (it’s common that header flanges have to be ground flat after final welding. Small misalignments at the flange-end mean big misalignments at the collector.

4 Oct 2009

The exhaust. Lots of time is spent placing the turbo while keeping space for two wastegates. Once located, the turbine flange is temporarily welded in place, and the turbo removed. With the flange fixed in space, the two rectangular secondary tubes are added, then the collectors. You can tell which welds I did and which were done by the experts… Fortunately there’s enough Eastwood polishing materials left-over from Kimini’s header to make this one shiny, too.

Once the collectors are in place, the fun starts, creating primary tubes connecting the cylinder head flange to the collectors. Romex house wiring serves as the mock-up material. The trick is to bend it with the same radius as the tubing – no cheating. At the end of the day, one primary is tacked-up, but as was re-learned, an exhaust takes more U-bends than expected. The thing with 321 is that it’s really expensive so there’s no rush to buy too many up-front. Hopefully they’ll get here before next weekend. The book will have more pictures and details on assembly ๐Ÿ˜‰ Fun stuff.