VL head measurements

[sny]

Measuring head volume. (inspired by Steve's book) I wanted to see if the heads I have are close to the same size since they have a different bowl shape.

Front head is stamped 9.3 with a walled bowl. Rear head stamp looks like 9.4 and has a rounded bowl. Tried covering the head with plexiglass and pushing water in through a hole and never got more than 8.6 into each head. Then I tried no plexiglass just to see what I could get to sit in the bowl without it spilling out. Front head could hold about 9.2 and rear head was closer to 9.

I did multiple passes, verified the syringe numbers were accurate and made sure I wasn't getting any air in so I think these numbers are pretty accurate.

Now my question is how important is it to have the heads match?

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[Steve Slocombe]

I've pulled down well-used engines with a high compression head on one cylinder and low compression on the other, so I would say not very. You've got the sought after 1930-35 high compression heads rather than the soup bowls used on the sidecar bikes, so I'd quit while you're ahead. Blueprinting, or cc-ing the heads may be important on modern race engines, but the flatheads are very forgiving about inexact set-up.

[sny]

Thanks Steve, "very forgiving about inexact set-up" is what I was hoping for! I keep thinking I'm almost done getting all the parts together for this engine but then I keep learning new things to look for.

_Eric