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Interesting topic, as I'm looking at regearing my 80 LTD to compensate for the 18" rear wheel swap. The taller rear tire-whee combo is sure to affect acceleration, plus I simply want a lot more snap down low. I could care less about top speed, as this isn't a bike that I even ride a lot.
My thoughts were a 14x45 combo but going to a 520 pitch chain. I've done 520 swaps on all my modern bikes and with a premium chain there's no strength issues at all and a huge reduction in unsprung, rotational weight.... That's all flywheel weight. I don't see much mention of doing a 520 swap here.

I run 18/40 sprockets with a 530 chain, it's equivalent to the 15/33 gearing that was stock with the 16" rear wheel on the LTD, but I have an 18" rear. When I looked in to the gearing for mine, the 18" rear came with 15/35 sprockets and the 16" with 15/33, allowing for the different wheel and tire diameter the overall gearing was the same. I wanted to go higher so I went with the higher 15/33 equivalent ratio and the larger diameter 18" tire. To me it still seems pretty low, I'm in 5th gear in no time when short shifting and at 60 or so you feel like there's a lot of pull in 5th. I do have 28mm carbs, a 1075 kit and 4-1 exhaust, on the minus side I am at 5,000 feet of altitude, so I'm not making lots of extra power.

I cannot even imagine going to 14/45 that's a 3.21:1 final drive ratio compared to a 2.22:1 on mine, that would seem horrendously "thrashy" to me, but I guess it depends on your goal. You'd be doing about 5,800 rpm at 60 in 5th with that ratio for a top speed of about 88 mph at 8,500 rpm.. I think you'd find first so low, you'd be better pulling away in 2nd. Regardless of overall ratio I wouldn't run as small as a 14 tooth on the front, a very tight angle for the chain to go round the sprocket, more friction and chain wear.

I am running a 17/38 = about 2.23....on the stock wheel tire combo I ran a14/35= about 2.5. The bike is not as snappy as it was before, I am thinking of going up to a 42-43 in the rear= about 2.47. Dunno.

15/35 has you at about 5000 RPM at 70 MPH. I have 16/35 and I'm at 4000 at 70, 3500 at 55.
Steve

I have run 14/37 a few times when riding my KZ1075 with my +120hp, giant cubic in V twin Harley friends just to torture them mercilessly!!
They won't even accidentally accelerate too fast from a light, fearful that I might think they want run me a few blocks. LOL