Stuck side seal in a rebuild engine
 

Front rotor is experiencing a single lower number of the 3 bounces.
Was anyone successful in freeing a stuck side seal using chemicals?
The engine is a non turbo S4, I did switch over to OMP metered 2-cycle oil.

Any thoughts?

It's a fresh build? Do you have a catalytic converter?

Run a gallon of water through the engine. Use vacuum nipples on the UIM towards the front of the engine. Have a friend rev the motor to about 3k rpm while you stick a clean piece of silicone hose in a gallon of water. Don't go too crazy with it, I'd split the gallon up into about three or four 'pulls,' let the car idle normally and cool off in between.

No cat, Racing Beat piping all the way. Engine was rebuilt 300 miles ago. I was trying with sea foam trough the same nipples you mention with no luck. Using water with the attempt to decarbonize a stuck seal, I'll try and see what happens. I could run the hoses inside the passenger compartment that way I can drive the car and control the amount of water that enters the engine.

If it's stuck after a rebuild, it's probably not carbon buildup sticking it. Try forcing a gratuitous amount of oil through a vacuum line and spin the engine over by hand a few times. Let it sit, spin, sit, spin, etc. It'll smoke like crazy. There's a few different ways the seal could be stuck. One possibility is a burr is keeping it pinned down, which would probably take a few redlines to unstick it.

if it's that new of an engine and hasn't freed up by now, nothing you do is EVER going to free it up. tear it back apart.