Whining about my carb problem

[DeltaMustang65]

Taken directly from fat0eknee's latest topic:

I took out my mustang for the first time in months yesterday. This was after I read a topic here about mustangs getting in accidents when they sprung a fuel leak after sitting too long. It was pretty fun, the single mothers and their kids were checking me out. Anyway, this is leading to a bit of a nagging issue I've been having since I stopped driving my mustang daily.

My mustang doesn't seem to want to start unless I take the top of the air cleaner off. I checked the choke clearance and although I haven't actually measured it (since I highly doubt it's the problem), it hasn't changed and it's wide enough to stick a standard screwdriver shaft through. It starts fine if I drive it regularly, and it runs great even after being in storage. The little 289 can still howl those tires nicely, not the screech those little ricer tires have, but the sound of spinning tires that have some semblance of traction. There's still the tiny lag at about 1/3 throttle, but I'm assuming that's because I never got around to getting it professionally tuned since the new intake and carb were installed. All in all it's not a big issue, it just seems very odd to me and it'd be nice if I knew what the deal is.

P.S. I just got my "user ride" page done. I was looking up info on factory parts and I was wondering if Ford used cast aluminum pistons? For some reason, I had it in my head that they were iron, but what do I know.