I've put two new cyls on my tiger over its life.. the last one just last week.

1) it took 3hrs to see a 30^o drop in CHT on the new cyl.

2) the factory new IO-550 had test stand time on it.. it was enough
so I didn't see a drop in CHT, or I was too busy trying to fly to notice.
http://rob.com/lancair/2002.03/550.jpg

Still on mineral, Rob

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Utopian Maturity: Eternity, Liberty, Equality and now Fraternity & Altruism.