So I have a 94 Toyota pick up 22 Re motor. I just put a new head and timing chain on and started to fire it up and it just backfires. It actually backfired so hard it blew the muffler apart. Help please!! Any ideas?

 

Verify correct cam/crank timing. Verify distributor stabbed correctly, go from there.

 

You have a timing chain issue. The intake valve is open when the spark occurs. Blowing the muffler apart is unburned gasoline vapors in the muffler, can be impressive. Sorry but the front has to come off again so you can time the crankshaft to the cam correctly. Look at your colored links and make sure they are right and the piston is at TDC and both valves are closed on #1 . I hate doing things twice, its bloody awful.

 

Once you have those verified the next step is to pull the valve cover, set the crankshaft to top dead center of the compression stroke for the front cylinder (crank pully mark lines up with 0, might be worth the time to pull #1 sparkplug and insert a plastic straw to verify it is fully at the top, have someone watch the straw to verify it stops moving up/outwards), verify both of the rocker arms wiggle (tdc compression). Now look at your cam sprocket, the dimple mark should be just to your left of vertical, if I recall correctly it's about half a tooth to the left, the dowel on the camshaft should be at the vertical position (12 on a clock face).