27 Feb

Moving the turbo over aft of the exhaust ports means fabricating a new exhaust manifold, either starting from scratch or seeing how much of the old one can be used. I doubted anyone could use my header since virtually all K-series engines are at the front of cars where it wouldn’t fit anyone’s engine bay, never mind being turbocharged. It was cut along the exhaust flange, then each primary knocked apart at the slip-joints, then the 2-1 junctions cut off. I may end up buying a new T3 twin-scroll merge collector since that’s the trickiest part. That said, most available parts are setup for thick 304 stainless pipe, not tubing, so I may build that type for fun.

My brother stopped by and observed how, with the existing intercooler being removed from behind the driver’s seat, the dry sump tank could move there – good idea! It moves weight forward, frees up more space for the new intercooler, and results in slightly shorter oil hoses. The last picture is what sank to the bottom of the dry sump pump. Dragging a magnet through it turned up some very small steel bits but hopefully nothing went through the dry sump pump. That and the injectors will be sent out next week for cleaning and inspection.

26 Feb

Disassembled the engine in-place. The turbo is in perfect condition which means nothing went through it. The front cover was removed, then the head, then the #2 piston. The cylinder walls were in amazing condition – the hone crosshatching still clearly visible with no scuff marks in any cylinders, even in #2. The #2 piston showed some sign of impacting the valves though the valves don’t appear bent. The head will be cleaned and fully checked out, then reused assuming it’s not cracked.

I sent closeup pictures of the cylinder and piston to the engine builder and he suspects I had a fuel or ignition problem. The injectors will be sent out to be flow tested and cleaned. I don’t really understand how a lack of ignition could cause high heat, but what do I know.

The reason the engine was disassembled in-place because since the turbo is being moved; the exhaust manifold flange’s location must remain fixed until it’s mocked up. Moving the turbo closer to the exhaust ports greatly reduces the surface area of the manifold and feeds more heat into the turbo instead of the engine compartment. The car’s been running without a muffler for many months because of how well the turbo acts as a muffler, and it finally occured to men that not having a muffler frees up even more space for the new intercooler. (If I ever run the car at Laguna Seca with its 92 dB sound limit, an external muffler will be temporarily attached.

24 Feb

A lot has been going on, mostly reading and talking to knowledgeable engine people. One engine guy says the plugs absolutely show signs of detonation, one said maybe, and one said no… nice. The pictures are the best I could do with my cellphone (my good camera doesn’t have a macro lens yet) so sorry for the slightly blurry pictures. While I feel compelled to point out that the tuner set up the timing tables, it was my responsibility to keep a close eye on the plugs.

I’ve been wavering back and forth between building another turbo engine and “bowing out gracefully”, resigning myself to a less-powerful normally aspirated (NA) engine, but one presumably more reliable – maybe. The “problem” is that I won’t be happy with 200 hp, or even 300. While the Honda K-series engine can indeed produce 350 hp NA, it’s not rocket science how it’s done. A CNC-ported head, over-bored, sometimes with a stroker crank, and then spun like hell. I don’t mean 8000 rpm, or 9000, it’s often 10,000+ rpm. That seems bad to me for reliability, never mind being many $1000s more than a turbo engine. Such an engine is probably awesome for drag racing where it’s run hard for 10 seconds then cools for many minutes. On the other hand, drive 20-30 minutes on a road course and I just can’t see how it’ll last long. Would it last longer at 10,000 rpm than a turbo engine would at 200 kpa and 7000 rpm? I think I’d bet – no. Many people will say that turbo cars are unreliable and a big pain in the neck at the track, and while they aren’t wrong, I also feel many of those cars cut corners. I’m convinced it can be done and I’m willing to give it another try.

Things I plan to do differently:
1. Install a much larger intercooler across the rear of the car*
2. Have my ECU calibration and protection setup professionally reviewed
3. Run less boost at track events (though the intercooler may allow more)
4. Inspect plugs after every session
5. Work out some sort of protection deal with God

*For some time I’ve been thinking of moving the turbo over to behind the engine near the exhaust ports – there’s space. It would free up a lot of space around where it is now and no longer bake everything in the area. It would also place the compressor outlet close to the new intercooler, the air filter assembly would have to move as well, to “somewhere”, and the intercooler-to-inlet distance would increase, but it’s probably a net gain overall.

The fun pictures and video will come later, too much going on right now.

21 Feb

Two years ago, Midlana’s first Willow Springs track day was cut short due to the fuel filter being installed backwards – my fault. Last event I spun off in T8-9, damaging a couple of body panels and my pride, but nothing serious. This weekend, well, read on…

Saturday morning we ran two skid pad sessions in which I found drifting Midlana to be harder than expected. Due to the size of the circle, Midlana was either at the top of first gear or the bottom of second, neither being optimal. The top of first meant hanging around 6000-7000 for an extended period of time, which I didn’t like doing. In second gear, the car pushes wider than the smallish circle we had to follow. Any time you see videos of cars drifting – on Top Gear for example – they don’t have a set path to follow. The driver’s left to reach the speed he wants, pitching the car sideways and using the throttle to steer the rear for the camera. I think every car has an optimum speed at which to drift and be able to easily control it. Or maybe it’s just my lack of skill…

Anyway, after I’d finished my second skid pad session, a late model BMW M5 went out and threw a rod due to oil starvation; a very expensive weekend for the owner – I would become more understanding later…

They then had us run a short version of the Streets of Willow course and we were only allowed to pass on the one straight. I got stuck behind a BMW that wouldn’t pull over and got annoyed, so I let the newish Porsche GT3 behind me by to beat on the BMW for a while. The Beemer eventually relented and let us both pass so I then got to see if I could keep up with the GT3 – he couldn’t get away and boy was I having fun! Full disclosure: the event was a class; there was a good chance the owner was either new to the car or inexperienced. It didn’t matter much to me as I was not only able to keep up but had to lift so I didn’t run into him. He wouldn’t let me by because he had the “faster car.” And then…

Heading down the straight I had just shifted to 3rd when Midlana suddenly lost some power, like it was running on three cylinders. At first I thought I had blown the gearbox because after pushing in the clutch, it was still idling. I coasted to the side of the course, shut it off, and thought about my fate as I waited for a tow. I realized that things were bad, that one way or another I was going to have to pull the drivetrain, I just didn’t know why. Through the helmet and earplugs I couldn’t hear what the GoPro – mounted to the chassis – heard, the rattling of a connecting rod…

So maybe you’re wondering “what did the ECU datalogs show?” Good question and I wish I could tell you, because the effing ECU datalogger didn’t record it! It did record the car warming up in the morning, it did record the two skid pad sessions, and it also recorded driving from the trailer to the hot pits before going out on-track, and that’s the last recording – extremely frustrating to put it mildly. Posting questions on the manufacturer’s forum has resulted in silence… hmm. Working with what I have for what happened is the GoPro video. It’s not high enough resolution to be able to read the values, but I can see that oil pressure, oil temperature, and coolant temperature were in a green font, indicating that all was well with the engine. It wasn’t until later when looking under the car, we found just how dire it was – a hole through the block and pan. Somewhat surprising, instead of being upset about the cost, the amount of work, or the downtime (all of which will be substantial) what keeps going around in my head is “why?” and “what should I do different to avoid this next time?” I’m completely mystified why the engine failed because:

1. It was built to withstand 9300 rpm – the rev limit was 7700 rpm.
2. The rods can handle 800 hp, I was running 400
3. The pistons are a conservative 9:1 compression ratio
4. The block is sleeved, typically only necessary when running more than 600 hp
5. Boost was 18 psi on ethanol, which is around 400 hp
6. The ECU protects the engine from oil and coolant over-temp, low oil pressure, MCT protection, and knock protect (though I set all of these up).

This evening I sent the picture of the plugs to a buddy who used to build 1000+ hp Honda drag engines. As soon as he saw the close-up picture he immediately said that in his opinion, I killed it due to detonation. A very bitter pill if true and I’ve forwarded the picture to the engine builder to get a second opinion. I’ll post more pictures this week, along with the video of chasing the GT3, which almost made it worthwhile.

15 Feb

Increased the left front camber 1/2 turn and the right rear camber a full turn, whatever that ends up being, to better balance the car.

I had the day off so did a test drive into the back country: up Palomar Mountain, down the east side, across Mesa Grande then back through Ramona and Highland Valley Road. Unfortunately it was ridiculously warm for February, around 90 degrees F, never mind getting stuck in an endless train of RVs and toy haulers returning from their weekend desert outings. Both my brother and I have a habit of driving up Palomar Mountain at about 30-40 mph – never using our brakes. It makes for a less-threatening-to-others approach to test drives; no spinning tires, no drifting, no hard acceleration, yet corners are nearly traction-limited. It’s saved us several times coming around a bend and finding a cop sitting there. Anyway, around a few turns the car was really loaded up but felt much better than before, so that’s promising. My brother said “so what you’re saying is that I figured it all out for you.” I said, “well what happens if it still spins off on-track?” His reply was, “well in that case it would mean that you obviously did something wrong then.” I see…

I’ve started hearing something loose in the car, like a component not fully-restrained somewhere behind or near the driver’s seat. It’s noticeable during even slight acceleration and also when swerving back and forth. I got under the car and couldn’t find anything obvious other than the coolant lines that go up and over the fuel tank being a little loose. I jammed a shop towel in there to see if that “fixes” it, since there’s poor access and nothing to tie them to. The engine mounts are fine, the suspension arms are fine, and the oil-to-coolant heat exchanger is well-restrained – I thought sure that was the cause but nope.

When I pulled into the garage and shut off the engine, I was enveloped by a strong smell a lot like acetone. It was as if my wife had used fingernail-remover, but she’d never do that in the garage. I asked her if she’d been doing anything in there, nope. I hadn’t done anything other than backing the car out. It turned out that a 15-year old can of spray paint had developed a hole in the side of the can, spewing very old and very stinky paint all over – made a sticky mess. It was a reminder to go through every bottle and can to decide what should be kept around and what should be discarded

Using the spreadsheet from the original Midlana design, I tried moving the dry sump tank from where it is now (aft of the rear axle) to way up front, to see how much it moved the CG of the car… 1%. Bah, that’s not very much for the amount of work and expense (two fairly long -12 and -16 AN hoses. Also is the thought that where would I want the tank to be in the event of an accident. Up front, it’ll get squished and spray hot oil all over, probably on me. In the back, it’s at least be contained in the engine compartment. Meh, right now I’m not feeling driven to move it, but I’ll have to see how the car’s handling is this weekend, whether moving the CG forward is that important.

The weather forecast for Streets of Willow is very promising so looks like it’s a go. My buddy Kane should be joining me for at least part of the weekend; having someone there who’s handling photography makes everything go much smoother. Hopefully he’ll be bringing some gear that makes the upcoming track video extra special :).

13 Feb

Took the car in to get the alignment checked to see how close it was to where I thought I set it. On the way there was a bit of excitement: two drivers on the freeway got into a serious case of road rage, stopping side-by-side on the freeway in the middle of heavy traffic, waving their arms and shouting at each other, then taking off, weaving in and out of traffic, then doing it all over again. During one of their “standoffs”, everyone at first came to a stop behind them, not sure what to make of it, then we all got annoyed and went around. After they finished yelling they took off again, cutting through traffic which was now ahead of them. They came right by me and I could see the guy in front was thinking of cutting into my lane, but then turned the other way – maybe the funny-looking car threw him off. I’m just glad they didn’t take out anyone and didn’t see them again; I guess one cooled off or the other got away.

The alignment. The shop had been recommended by several websites as being race car friendly and being able to accommodate low cars. It was surprising to see that instead of a high-end laser alignment rack, they used clamp-on devices and strings, not all that much different than what I do at home. At the front, camber was 1.875 degrees left and 2.1 right. Caster was 8.75 degree left and 8.5 right. Front toe was zero. At the rear, camber was 2 degrees left and 1 13/16 right. Left toe was zero and right toe was 1/32 degrees out. I had the shop change rear toe to 1/16″ in on each side for a total of 1/8″. It was very useful watching how he did the alignment, so I can do the same at home.

7 Feb

Corner-weighed the car: 1718 lbs fully loaded, full tank but without me. Rear weight percentage is 65.4%, not as much as I thought but I want to run the numbers and see what moving the dry sump tank to the front of the car would do.

Anyhow, after that, went out for a long test drive in the back country. We’re having strange weather, last week it was freezing cold with near hurricane-force winds and tons of hail. One week later it’s 80 degrees. Anyway, right as I was about to turn into one of my favorite twisty roads, I caught sight of a Ferrari turning ahead of me. The first part of the road is straight and he took off like a shot, so naturally I had to see if I could catch up. I did, but he also let off to let me pass. Well that backfired – he knew as well as I did that when two cars are doing “spirited driving”, the guy in front has all of the pressure. He’s first to find out what’s around the next corner: open road, dirt scattered through the turn, water, squirrels, bicyclists, or a cop (turned out to be a bit of each). The guy behind doesn’t have to worry about that stuff and can concentrate on just keeping up. I refuse to get into “who’s got the bigger pair” so drove at 8/10s. Several times the Ferrari would lag back then catch up in a hurry. Toward the end of this road is some pretty twisty bits, so when he lagged behind the last time, I decided, no, you’re not catching up this time. At the end of the road I was pulled over, out of the car, putting on my sweatshirt because it was getting cold at altitude when the Ferrari caught up and pulled over.

I had a long enjoyable talk with the driver who turned out to be an automotive journalist. He was doing a road review of Ferrari’s first turbocharged street car, the 488 GTB with 661 hp. I learned that the base model has a turn-your-head-and-cough price of $250,000, with this one having another $100,000 in options – yikes. He used to work for Road and Track and is now a freelance writer who knows a lot about everything automotive. He was interested in Midlana and asked a lot of questions, so I was happy to open the engine cover – that’s why the cover’s off – no I hadn’t broken down 🙂 The place we stopped was a very old section of road which is hardly used, that’s why he’s sitting in the middle of the road.

Anyway, back to Midlana’s suspension, it’s definitely working better. The back end can still be made to come around but no longer happens as suddenly and is much easier to control. We’ll have to wait a few weeks to see how that translates at higher speed, but it seems promising.