The guys who bought the Kimini body mold are looking to sell it. Don’t know if they changed plans or pulled some shells from it.
Beta-builder Jim is doing his build in a slightly different order than I am since he doesn’t have to mess with a turbo. He’s about to start on the A-arms, flying without a net since – while I’ve written the A-arm fab chapter – I’ve not yet actually followed the directions!
I’m coming down with something… hope it’s not the H1N1 thing… it is flu-like.
The two beta-builders help keep me in line, pointing out issues and asking questions that, if left unanswered, will be amplified once the book is released. Part of the burden of keeping them busy is the occasional grenade they lobe in, asking some innocuous question or asking about a dimension of such magnitude that it gives me a good scare. The last one was a big deal, something about the rear wheels not fitting(!), but a fast mock-up appears to show all is okay. This could have been a big deal since axle lengths come into play if there’s something major amiss in the rear axle track width. Whenever one of these problems gets lobbed in, it always makes me wonder what they think, after they’ve discovered I don’t know as much as they thought… That’s the deal with beta-builders, they see all the dirty laundry.
Both are apologetic about pointing things out, but that’s exactly what I need and the input is extremely valuable. Also helpful is the input from the third beta… guy. He’s not a builder, but has been a big help on quickly getting the manuscript into Latex, and who has recently started an initial copy-edit. He’s also reluctant to mention my many errors, but the truth is, the more the better. I won’t get my feelings hurt – much – because I already know my skills are less than perfect! (Oh, and he says the manuscript has already caused him to buy a welder in anticipation of buiding his own…)
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.
Ordered fasteners for the turbo system… nuts, just realized I forgot to order bolts for the muffler flange… oh well. Will work on the rest of the exhaust next, and if there’s time, figure out where the remote oil filter is going, which determines oil supply line length. The plan is to tap into the housing for oil pressure, temperature, and the turbo oil supply.
My brother is leaning on me to go with him this weekend when he takes his Super Stalker to Button Willow raceway – sprung it on me today since his other passenger backed out. But, Midlana’s gets built because I don’t do other stuff. That’s what it comes down to, doing family activities, or selfishly working on the car – the all-consuming time-sucking car which I really enjoy working on. So now, if I don’t go, I’m the bad guy; wonder if he regrets badgering me about how slow things are moving along, How many times I’ve heard, “Is it done yet?” Well, it’s getting done becomes it’s being worked on.
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. What’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.
The book is moving right along, currently at 268 pages. It’s worked on every evening, while the car’s worked on each Sunday, and more when I can (three weeks off coming up at the end of the year.) The ratio works out about right; 6 evenings of typing keeps up with one day of fabricating.
I want to start the engine, so after the exhaust is done, the oil system will get sorted. Dual remote filters and an adaptor plate will get mounted, along with oil supply and return lines to the turbo (so the bearings won’t fry during a brief startup.) Water lines can wait until later; I just want to run it for 30 seconds or so, not minutes. A complete fuel system isn’t necessary either (a hose stuck in a gas works fine for test starting). That’s because I don’t want the real fuel tank with gas and fumes in it stinking up the garage for months while everything else is finished. Anyhow, after the oil system’s plumbed, electrical work will be tackled.
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.
Received the additional exhaust tubes, so Sunday will be busy. Made the decision to sell what turned out to be an expensive intake manifold and am replacing it with a part that fits with less bother for less money. Right now everything necessary to make big progress is here; it’s now up to me to make it happen.
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 😉 Fun stuff.
Good news on the shifter; it turns out all the drag is being caused by the very snug end seals – nearly five pounds of drag. Remove them and it works great, the shifter centering itself as it should. The seals however, must remain in some form since they’re the sole protection against dirt and water getting between the inner and outer sleeves. They were trimmed back to decrease the contact area but still retain a seal, and now all is well. Excellent, since it avoids a lot of extra work, and the exhaust manifold can be concentrated on.