For the Baltimore, I just put on bulge. It doesn't have enough DP to pack on the heavy armor, so anti-torpedo is the way to go for me, because I personally HATE being torped by a noob with no skill from across the map. With that setup I think I went 25 knots normally, OH being 37. Noob DD/CLs shouldn't be a problem for either, if you equip them with the level 51 triple 8" guns. Their range is two to three times more than any DD or CL can do.
In Pensacola though, I would equip the BB guns on it. To use them effectively (and have good spread) I made sure I had at least 110 veterans and 300+ experts. Same as on the Baltimore, I relied on range and firepower rather than armor. Even with the triple 12" guns, I was able to put on 255" of bulge, and go 24 knots or so, with OH being 36. That's just my reccommended way of doing it, but it's your choice to opt for the anti-shell, or anti-noob.

I agree with what jubdub said, but remember to put on 0.2 inches of belt even if you arent going to armour up the Pensa/Baltimore, 0.2 belt will half damage taken from torpedo hits.

The Baltimore/Pensa are very good ships if you exploit their range advantage over small ships rather than relying solely on armour. The best setup for the Baltimore is to use the Trip 8" Mk 14 Ls with Light HE and the Trip 12" Ls with Light HE on the Pensa and just shell them from long range, but you'll need very good gunners for this. If you dont, you can use the regular versions of each gun and Medium/Heavy HE ammo as long as you keep a relatively safe distance from the from the guy your trying to shell.

Its not always easy to use range to your advantage in Blitz, especially for Hobbit War, but it will become extremely useful once your past level 61. Great Battle is a very different game from Blitz. GB is all about range and tactics whilst Blitz is everyone rushing to the middle for a giant slugfest (not that theres anything wrong with that, its a nice change of pace).

I'm assuming that you are new. If you are struggling to learn manual AND playing in blitz, put on a stack of belt. Let them drive up to you and be a big slow moving pillbox. Yea, other people will tell you that its not the best thing to do blah blah. Thats because they have mastered manual already.

For you, a slow moving ship means its easier for you to adjust. You aren't going to go ripping an shooting at 40 knots. If you need to go slow to shoot, then you midas well have the belt and bulge. DO NOT go into GB like that.

well... Armor up your CA its not such a great idea...
im sorry about being the one that brings the bad comment for u... but US CA are to be played using range - firepower and speed...
you should only put 0.2 belt... (reduces torp dmg) 1 o 2 bulk head (for more ship resistance) and arround 40 to 70 bulge (anything more its just a waste of speed, US bulge can take some real punishment)

Baltimore: its a great CA, one of the very best in the entire game (the only real disadvantage its he's size) but like someone said before, he (unlike CA N.O.) can't pack any real armor, so you should try using his good range against incoming DDs, what you need to do its learn some basic line tactics... if any enemy rushes on you just go back and keep firing at him...

if your guns fire wide open try putting some vets and experts on your gunners, CA 8's can blockshot at very low lvl so your spread will be decent after some vets
if you dont want to spend money in that matter go back to Cleveland and use it in GB as AA ship (only using sec. guns)

Pensacola: one of the best CA for ASuW, you have some advantages over Baltimore, the first its that you can carry a BB FCS and you can carry BB guns, but besides you can carry a lot of armor... i have to say that it can work a Armored Whore set up for pensa, using triple 8' Mk 14L instead of Triple 12'.... but remember putting the same belt bulk and bulge than with balti...
at last i'll have to say that the very best config for pensa its similar to the one in baltimore (only bulge) and using triple 14D

your spread with 8 triples will be quite better than with Baltimore due to BB FCS, but since you got only 2 slots you'll have less firepower. You can also try Triple 12 L or triple 14 D... be aware that you are going to shoot quite bad with any gunners that are able to enter Blitz but when used with High lvl gunners in GB you can one shoot any DD-CL even some CA. besides triple 12 have 45º angle that its quite hard to manage in Blitz

whatever you do, whatever CA you may choose, use manual shooting and aiming FCS, its time for you to learn how to use it, i know its hard the first days and you might be thinking that you will never hit anything, but when you learn it you'll be ready for GB

Well, I already use Manual FCS, and I know how to use it pretty well.

I saw that people saying that I needed around 300 experts and 100 vets on my gunners. I already had the 100 vets on them, so I dished out some cash and bumped their experts.

The difference was night and day. I can actually hit things at max range now, and I can wreck things at close range fairly well.

Suffice to say, I don't need that armor anymore. Thanks for the advice guys.