pfaber, I struggled with throat hit for a very long time.
I tried high nic, everclear, mods and every other thing that I've seen suggested and got nada.
Not too long ago I ordered a bottle of Diablo Loco from Totally Wicked which is a Decadant Vapor flavoring and, bingo, throat hit.
But I have to caution you on how much of this to use...the description at TW says it is 200X hotter than tabasco sauce and refers to it as 'pain in a bottle'.
Turns out, that description was quite accurate. Keep in mind that I tried some pretty extreme ways to find TH because it was simply not something I could do without and none of them fazed me. There were a couple of occasions when I'd order a new liquid and think 'ah ha' I've got it, but for some reason it never lasted for long.
This stuff, though, is something you want to use in minuscule amounts like starting out with
one drop in, say, 10ml of PG or VG and then one drop of that mixture added to 10ml of juice. You might decide to work your way up from there, but keep the additions in very small increments.
So, I'd suggest trying all the other ideas first, but if you find that it just isn't working for you this might be something to consider.
Here's a link to the page that includes the information:
Decadent Vapours 10ml Flavour Concentrates
I bought a 10ml bottle and so far it feels like a lifetime supply.
Good luck!
Edit to add: Don and Kent who have posted above me are both extremely well versed in everything ecig - i have read and followed their advice on many issues along the way, and I'd recommend that others do the same. But I did try many different devices and atomizers and I guess I must have a much different reaction to the things that work for others when it comes to TH. Ultimately, I found that when I hit the right mixture of liquid I didn't even need a high voltage mod and I use a simple KR808d-1/cartomizer set up and still have a very good throat hit.