Yeah you heard it right.

Was able to achieve temps between 750-850 in the home oven without having to cut the lock or run it on the cleaning cycle.
First off, I just moved into my new house and we have a Viking oven to play with. The heating element is on top and I'm not sure if it heats from the bottom as well, but I'm thinking not. Top oven temp setting is 500 and then followed by broil.
When baking pizzas in the home oven in the past, I have always baked on one level below middle with the oven at 500F preheated for 30-45m. I had no idea what the stone temp was. Likely around 550, but don't know. Well recently I just bought a thermogun from sears and now able to read surface temps with a click of a button. Very cool.
So I had an idea for a new setup (new for me anyhow) that I hadn't seen before. Remember, I'm new here so there's only so much I have read.
Anywho, the set up goes like this. Set the stone about 3 inches from the broiler and heat up using a temp of 500F for 45mins, then broiler was turned on for 15m. Stone temps were checked periodically to see how high I could get it. I have no idea how hot the broiler gets but I know it's above 500. Well after 30-45m preheat, I tested 3 different stones and got surface temps of 650, 750, and 850! Likely due to the different properties of the stones.
1st stones are actually D-plates (deflector plates) from my Primo ceramic outdoor oven. It's the same material as the oven itself and I believe the material is kiln fired to around 2000 deg. So no worry about cracking there. There pizza stone is made from the same material but is glazed on one side. I'm in the process of having the other side glazed as well, so I had to use the D-plates for this experiment. It's possible that these would have gone higher into the 800's and that i was just too impatient. When the temp seem to stay around 650, I cooked 1 pizza and then added stone #2 on top of them for testing.
Stone #2 is a 16x16 natural slate Tile from Lowes for $4. It is rather thin at less than 1/2" and dark in color. Not a great choice b/c it ended up cracking along the middle but was able to achieve 750F.
Stone #3 is a 16x16 natural travertine tile from Lowes for $4. This is the porous travertine. DO NOT use the smooth travertine as the pores have been filled in by the manufacture with

who knows what. The one I used for the test is in it's natural state. It's only been cut by the manufacturer. This stone was tested after all the pizza's were already baked on stone #2. I assumed that it wouldn't reach as high a temp b/c of the white color but I got a reading of 850F in the center of the stone right under the broiler. As you move away from the center, temps started to drop to 750's.
So 1st pie was baked on stone #1 (D-plates). I was concerned about burning so after the pie was loaded at 650F, temp was turned down to 350, then up to 400, and 450 after a few minutes since I realized it wasn't gonna burn. So color of the pie is a bit light.
Here is the setup. Oven is set to 500F for 30min, then broiler is run for 15min or until stone reaches desired temp. Once pizza is loaded, oven temp is turned down to 475-500F. Stone is about 3.5" from the burner/broiler and pie is about 2.5" from the broiler. Pie is then baked for 5-6mins turning once or twice. The back of the oven is hotter than the front. When I turn the pizza with the aluminum peel I take a peek at the bottom to make sure it's spotting properly. After 5 mins or so, I turn the broiler back on for 30 seconds or so.
You have to watch the pie very closely at this point or it will burn very quickly. Broiling at the end chars the top crust and cheese. Again baking times here are around 6 min at an initially stone temp of 750.
Next time I will bake with stone #3 at a starting temp of 850.
Pic #1 is the slate stone(stone #2) ontop of the D-plates (stone #1). I stacked these for the thermal mass.
Pic #2 is the travertine stone (stone #3) on top of the slate stone (stone #2). High temp of 850F here!