Daily Archives: January 15, 2017

More reminders that I’m getting old

When I woke up this morning my foot was swollen and felt like someone had been beating on it, again, and my cognitive functions pretty much haven’t functioned most of the day. Part of the latter problem is despite being exhausted last night my brain was still firing away at 0500 when I had to get up at 0900 to get ready for church, and I haven’t been back to sleep since. It’s like a switch gets thrown at midnight from “wasted” to “creative” and if I can’t get up and do something like writing or building I just race through ideas all night until something else switches “off” so I can sleep. Now I’m wandering the house in a haze trying to put two thoughts in a row, and failing at a third.

And there is a cat (Clint) sitting outside my office door demanding to be let in to do what cats do in my office: pretend it’s the world’s largest litter box. Actually that’s not fair, he wants to Be With Me because I am His Favorite Person In The Whole World™. Clint shows his pleasure at being with me by clawing my legs and stomach trying to get situated in my lap both initially and any time I move, and shoving his face into my armpit constantly. I don’t object to armpit-butting and lap-sitting, but the waving of claws in ecstasy gets me in the chest, belly, and sometimes face and/or crotch. As a result I have invoked the “No Claws Clause” in the adoption contract that allows me to remove a cat from the room for using claws inappropriately.

Back to being creative, or else, I’m still trying to figure out the mid-Bucket (and how to spell mid-bucket, obviously). Testing various risers has shown that putting the gas tank under the seats raises the seating position too much, the ideal seat height is making the cushion 5″ above the floor and the 10″ riser puts me too high in the body as there would only be about a foot of body side between sitting in the car and getting tossed out of the car. Visually going from the 5″ riser to the 10″ is the difference between sitting in the car vs sitting on the car, looking like an adult in a real car to looking like a kid too big for his toys. That means I have to find a place to put the fuel cell, and a place to put the trunk, that don’t unbalance the car either visually or dynamically. The original idea was to put the fuel cell behind the rear axle and under the rear trunk with another trunk up front between the original firewall and the front axle. That one got dumped because of too much weight in the rear and no space in the trunks for a full-size suitcase. The current (pre-underseat) configuration has the fuel tank under a tiny front trunk and a bigger trunk in the back. Neither trunk is suitable for hauling temperature sensitive cargo like chocolate bars or rolls of photographic film in a TX August. The front trunk is right behind the radiator while the rear trunk has the hot exhaust on either side and the engine in front. Lots of radiated heat sources around the rear trunk to raise the temperature inside the trunk even though the main source of heat has been located on the other end of the car. So after thinking some more and consulting the fuel cell pages in the Speedway catalog I decided to put in a 16 gallon cell that will fit under the steering column and allow a small trunk behind the axle, but still allow me to run E85 and have enough range to get to Nashville from Casa de El Poeta without running dry at the projected fuel economy for the car of 20 MPG highway on E85.

There was a lot of material in my EFI books on setting up an engine for E85 (AKA Car Booze) including tuning to max economy at part throttle while maintaining max power at WOT in the same fuel/spark map. It turns out there is a lot of commonality between tuning for fuel economy and WOT power, and it is entirely possible to have both. It is almost a case of having your cake and eating it, too. And with what can be done with an engine set up to burn E85 you can get more power than any pump gas while getting a carbon footprint lower than pump gas without factoring in if the ethanol was not fossil-sourced, which it isn’t. Getting the most power and fuel economy from E85 will take an engine rebuild to install higher compression pistons to take advantage of the higher octane rating, higher flow injectors to give some leeway on the fuel/air ratio at WOT, and a camshaft that will bleed some pressure off at lower RPM to allow even more compression which increases the expansion ratio and extracts more energy from the fuel at low power settings. From all the hype about compression ratios what is really important in economy is the expansion ratio of the burned gasses. Ideally you would like zero pressure to a slight vacuum at the bottom of the power stroke in an Otto cycle engine. This is a fact I picked up in first-year thermodynamics in engineering school. To do that requires a really small combustion chamber and a really large cylinder, AKA a high compression ratio. Which is why people looking for power and people looking to get as many miles per gallon as possible both go for as much compression as the fuel will allow.

AAAnnnnnd that’s enough rambling for today, bye.

Billed @€0.02, Opus the Unkillable