28 May 2008

Received the Wavetrac LSD in perfect condition. I’ll try to deliver it and the transmission to the tranny guy this weekend. I’ve been told that it’s “easy” to install… eh, could be, but I rather pay to know it’s done right.

24 May 2008

Sorry for the lack of updates but there just isn’t much to report. Spending time on the book manuscript, updating it with my latest thoughts and bringing it up to date to keep it in-line with my progress, such as it is. The idea is that when the car’s done, the book will be, too.

Assuming Kimini doesn’t sell soon she’ll be put into storage. I refuse to give her away at too low a price, but my sense of urgency to get going with Midlana is reaching the breaking point.

Bought a WaveTrac differential (Quaife LSD successor), a key requirement of the project. It’s a cool assembly, both a gear-type and clutch-type LSD – theoretically the best of both worlds. From people who do a lot of trackday events, the word is that clutch-type LSDs are good for nearly two seconds a lap, which is a lot of time. This is apparently due to the clutch-type diff continuing to work when one wheel is in the air, like when driving over berms, while the Quaife goes open in those conditions. I’m taking a bit of a risk getting it now since I’ve yet to hear how they do on-track, but expect good things. I’d like to get the tranny inspected and have it installed at the same time, just to get that task out of the way. That way it’s considered a ready-to-go item that I don’t have to worry about afterwards.

The engine, however, is a self-imposed bigger deal. It’ll need to come apart, inspected, then rebuilt for turbocharging service, though this can wait. On the other hand, if for some reason I can’t start on the chassis soon, it’s tempting to dig into the engine, that way at least some progress is happening. The downside is that an unused engine can have rust form on the cylinder walls and the valve springs can take a set. We’ll see… I can always turn it over by hand every few weeks.

18 May 2008

I had a professional Mechanical Engineer look over Midlana’s CAD drawings who gave it a thumbs up. He made a couple of good observations which I’ll incorporate. He shares my irritation with the SCCA rule that allows using 1.375″ x 0.080″ rollcage tubing – which can be neither found nor bent!

7 May 2008

A generous reader, Matt, volunteered to run my CAD chassis through FEA (finite element analysis). The chassis has already changed since last week and will probably change more, but knowing its approximate stiffness is helpful. The center tunnel has already changed, too, now a 4″ wide x 12″ tall affair with about 5000 ft-lbs torsional rigidity.

The pictures are of last Saturday’s Irvine car thing. Notables were the 1970 Porsche 917 and that crazy Nash Metropolitan with its big-ass engine. It was like a giant leaf blower when he drove in, the bottom-exit pipes blowing dust everywhere. With the idle surging up and down it made simply driving through the lot a chore. Amazing that he drives it on the street! Of course I suppose he could say the same of me. On the way out I couldn’t help but get a shot of Kimini next to it.

Not related to the Nash – really – I verified that Kimini’s top speed is 127mph, gear-limited. It was still accelerating pretty well so I’m guessing perhaps 135mph aero-limited, which means the drag coefficient is lower than expected. I’m happy. (Early Saturday mornings the freeway is pretty empty; I didn’t pass anyone during this test and endangered no one but myself.)