Chapter 15

Since last time, I have stripped down the chassis, painted it with POR-15 after sanding it down, removing extraneous brackets and welding on gussets and fish plates where I thought they would do the most good.  With that done, I have been bolting everything back together, and have determined that the LP tank that I used for trial fitting is shorter than the aluminum one I intended to use. That has required some creative thinking, but all is well now that I have modified the frame a bit. The motor/crank/input shaft of the v8 style transmission needed some revision. Turns out that the input shaft of the trans was 3/8″ too long, and so I had to shorten it, including shaving off some of the splines in the lathe.  When this was done, the driveshaft was now 3/8″ too short, so I had to make an aluminum spacer between it and the pinion flange on the differential. I have mounted a battery box under the floor, directly beneath the access door that I created just in front of the drivers seat. This should allow a 26R type battery to drop right in.  I have been working on the clutch mechanism, which is still a work in progress, and may ultimately change from hydraulic to manual. If this happens, I will be able to use both sides of the master cylinder for brakes. Many race cars actually have two masters, linked together, side by side to optimize braking power. When a proportioner valve is used, there are compromises in braking power which result. I may be able to eliminate this issue.

Another issue is the rear axle. If you have been observant, you will have noticed that the rear hub, from a big GM, has two cone bearings which somehow needed to each be tight up against the races with no slop. These are different sized shafts, and I made up a rather complicated two piece affair to accomplish this. In discussing the design with my favorite machinist, we concluded that there might be a better, safer way to go about it using parts that I had not previously encountered. Actually, all front wheel drive cars have a big bearing which has a solid mounting to the A-arms   on one end and a bearing supported disk with wheel studs on the other side. Motive power to spin the front wheels is transmitted thru splined half-shafts with CV joints which slide into the rotating splined center of the bearing. Now, if the A-arm side  is bolted securely to one swing arm (the driver’s side), the bearing/hub can have the disk brake rotor attached, and then the wheel. This supports most everything from one side. Then, using a chunk of a half shaft (actually the splines on the “inner” happen to fit), the passenger side can act as the drive shaft which has a flange to bolt on the rear sprocket. The outer-most extreme part of this shaft is then machined to tolerate a 1″ diameter pillow-block bearing which bolts to the passenger swing-arm.  I may have to do a little more beefing/triangulating the driver side swing-arm.  All this will set my completion date back some more, but after all, I am designing as I go, and when an idea really seems better I need to roll with it….literally!


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