Yes, YYZ is a preclear station. As long as things are on time you should be able to make it. Here are my notes from doing this walk last year (May, 2012). I went T1 --> T7, but the walkway is really between T1/T2 and dumps you out next to T6.
So I figured I'd update this thread with my findings from my recent T1 --> T7 connection at LAX.
I had a ~1.75 hr connection in LAX between T1 and T7 (international). I walk pretty slowly and was only carrying a large computer bag (~15 lbs) -- the walk took < 10 minutes. Someone in a hurry could easily clock in < 5 minutes if they aren't lugging a heavy bag. It took longer to walk to the gate inside T7 (post security) than the walk between terminals.
In general, the walkway is poor and LAX needs to do a **MUCH** better job to keep up with modern airports. Furthermore, the walkway has a cloud of smoke/exhaust due to the overhead highway part. If you have more time, definitely take the upper route for a more pleasant experience. Honestly, I would avoid LAX for connections if at all possible. If you can, stick to terminals 6/7/8 -- which are all connected internally (behind TSA security.)
There is very little signage (none?) indicating that you should actually take this route. The walk is lit, but I wouldn't call it "well lit" and I wouldn't really call it "safe" either. It's safe by virtue of the fact that the airport is constantly in motion, but it still feels less than optimal. The actual walkways themselves are in fair condition (nothing to really trip over.)
A couple of notes:
1. Exit T1 at the far right end, the crosswalks to T6 are just out the door to the right. Cross the "curbside dropoff" area and stand in the center.
2. ** Wait for the green crossing signal ** at the island thing. The button is on the left side. It will take a while (~2 minutes). Do not try to cross while the hand is red/orange, you'll end up pancaked on the roadway.
3. Walk across the left side by the parking deck, which then forces you to the right side as you get closer to terminals 6/7.
4. Eventually you come to a similar island thing near terminals 6/7. Repeat step 2 (button is on right side this time, and it takes ~2 minutes.) After you cross, there's a small curbside dropoff zone before you reach the actual terminal building. No need for a crossing signal there though.
5. Terminal 7 is to the left a pretty good distance. Terminal 6 is to the right (closer than T7.)
6. There's an outside escalator to take you up to the departure level.
My view on LAX is very skewed because I usually travel through ATL exclusively, which of course doesn't have any outside connections. Having flown through ATL, CLT, DEN, HOU, JFK and now LAX in recent memory -- I have to say that LAX is way at the bottom of the list. Terminal 1 was fair at best, Terminal 6 is in pretty bad shape.
-- Dan