I’m not filthy rich

My ticket did not have the winning Mega Millions numbers. To be precise my ticket had nothing in common with the winning numbers. The closest my ticket came to winning was the jackpot total printed at the bottom. And at the end of the news was the announcement that if nobody won today Friday’s draw would be for $2 billion. That’s roughly $44,000,000 for the first year after taxes. To put that in perspective the jackpot for tomorrow’s Lotto Texas drawing is $13,500,000 over 30 years, or less than a third of the post tax first year take home. And because I’m not super greedy, just regular greedy, I bought a ticket for the Lotto Texas drawing.

Lotto Fever has not been the only thing running through my mind, I have also been thinking about making the Subaru powered variant of the Sprint-T lighter. If my math is right, I can save 7 pounds by fabricating an aluminum housing for an aluminum 9-inch center section, but I won’t save any money and I won’t be able to find the right final drive ratio to match the Subaru 5 speed transmission for racing or cruising the Interstates between races. The available ratios are kinda thin taller than 4.11, and especially between 3.50 and 3.00 as in there was literally nothing in the current catalog between 3.50 and 3.00. OK looking in the wrong page of the catalog, there are actually 3.50, 3.40, 3.25, and 3.00 in the other side of the catalog. The street side of the catalog doesn’t get as low (high numerical) as the race side, but it has much more choice taller than 4.11. Anywho, just thinking out loud again, looking for better options and not finding any.

And I was watching some racing videos last night and saw a ISMA supermodified racer that was running an interesting setup with a ball joint upright on a twin tube truss beam axle. I could only see the back of the right end of the axle because the camera was on the right side pointed forward from the driver’s seat area, but it looked like an inverted Pratt truss because they wanted as much of the load carried in compression as possible to avoid welded joints under tension and still wanted triangulation. Or it could have been a modified Warren truss with one vertical member to provide a place for the 4-link to tie in. Either way it gives a way to run different spindles and hubs if I didn’t already have an axle and spindles. But I’m keeping options open for a replacement that is lighter than the boat anchor I have at the moment. Not that it’s an actual boat anchor, just like 10 times stronger than needed for a 1300 pound street car, and correspondingly 10 times heavier and it’s all unsprung weight. Unsprung weight is bad because it’s basically uncontrolled dynamic weight. Sprung weight, as the name suggests, is weight controlled by springs and dampers (shock absorbers).

One of the options I have been looking at was making an axle from a foam core and carbon fiber for light weight and super stiffness. I could build for the same breaking load as my steel axle, or go for the same yield load, but since carbon fiber has the same breaking load as the yield load but there is a huge difference between yield and breaking loads for steel I’m thinking there is a larger safety margin matching the breaking load. I was also thinking that doing a final, non-structural, layer of Kevlar I could protect the assembly from abrasion and contain the sharp bits of carbon fiber when it does break using the different moduli of the two materials. Simply put the Kevlar has about the same strength as carbon fiber, but it has to be stretched a lot farther before it breaks so what breaks the CF won’t rupture the Kevlar layer which then contains the broken bits unless the load or impact also tears the Kevlar. I could use the same spindles I have now or I could adapt aluminum upright/titanium spindle sprint car spindles, or I could whittle aluminum uprights to use lightweight GN hubs and spindles with the same kingpins and bushings as my early Ford spindles. The sprint car spindles and uprights are tempting but questionably legal for road use. Anywho, carbon fiber over foam is about 1/5 the weight of steel for the same breaking strength, partially because the foam acts to prevent the CF from deflecting but adds little weight, and makes manufacturing the part easier because it provides the shape for the part, just lay up and use wicking peel plies inside a vacuum bag to remove excess resin. So end result is stronger, lighter, and almost as easy to make as welding it from steel except for the cost of materials.

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