On my 82 242, the lower steering shaft is a very interesting shape. Just so we're clear, the shaft I'm talking about runs between the u-joint right at the firewall (base of the column) and the u-joint that sits on the rack/pinion shaft. It's the part of the steering shaft you can easily see under the hood. 8-10" long. The splined sections on either end measure .710"/18.1mm in diameter. However, in between the shaft swells out to an odd pseudo-rectangular shape that's approximately 41mm x 36mm (about 1 1/2" x 1 3/8"). There's a link to a picture down below.

That bigger part of the shaft has interfered with the V8 exhaust manifold in the car --- so that the engine is offset about 1/2" towards the passenger side and one of the primary tubes on that side still needs a dimple in it for clearance. The offset's not a problem -- actually helps left/right balance with the driver in the car. But I'm about to go with a different V8 and would like a bit more clearance in this area.

Does anyone know: 1) why the odd shape of the shaft? I'm guessing safety related - to be sure in an accident it shears in a particular place....but just a guess; 2) if that piece is solid all the way through?

I'm thinking of removing it and turning it to something close to the same diameter as the splined ends. Before I jump into that, I'd like to be sure I'm not missing something.

Picture of the shaft in question here --- http://i937.photobucket.com/albums/ad214/MichaelYount/LS3%20Engine%20swap/shaft_zps9kg6xeam.jpg
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82 242 5.0L; '10 Cayman S; '15 Honda Fit