Ballast Part 2

Since first making the ballast for the racecar, it has gotten bigger wheels and tires, all the aero bits added, the electric power steering column (and the heavier, faster ratio PS rack), and a few Hill Climb safety bits and bobs. With nearly an empty tank, it rolled across the scales about 59 lbs overweight.

1983 lbs, where my class minimum is 1924.

I was able to drop 1 of the two 5/8″ lead plates, and also cut about 1/4 off the other one.

I got down to 1932 (8 lbs over minimum).

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I’m generally not comfortable with that tight of a margin, but I never run with that little fuel, so there’s a bit more wiggle room than it would seem.

 

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Differential NVH Damper Delete

The NVH vibration damper on the input flange of one of my diffs has started shaking loose (a semi-common problem). Given that they’re not a critical piece, that they can be a critical failure. that they would be a royal pain to fix in the field (assuming I have access to air tools, which I typically don’t), and that I’m in the process of having them both in and out of the car before and after the hill climb, it’s time for them to go.

The piece in question is the big steel (? might be cast iron) cross sitting between the input flange and the differential housing. It’s mounted on a rubber donut bonded to the input flange.

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A few minutes on the press (for the good one, the other nearly came off by asking it nicely) and it came right off. A little time on the wire wheel to knock off the excess rubber off of the flange and it’s ready to go back in.

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I didn’t expect it would add up to much, but it did end up being a worthy gain (or loss, depending on how you look at it), taking 1.75 lbs of rotating mass off of the drive line. Like removing a small flywheel off the front of the differential. Success!

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