Help, I can't figure this one out, does not run smoothly
 

Oil overfilled, oil in intake, air filter oil soaked, intake oil soaked, smoked like on fire.
Removed air box and hoses, cleaned all oil in intake and throttle body, fresh new air filter, Cleaned MAF, cleaned eccentric sensor, disconnected battery, applied brake pedal to clear memory, changed leading plugs due to visible effect from oil.
Car has gutted cat, 1 oz two stroke per gallon at fill up

Symptoms are release clutch at idle, engine shutters/jerks at high idle speed without touching gas pedal. Feels like I am pulling a trailer extending through rpm range in each gear when at operating temp. Does not fell smooth, feels resistance.
Car starts up instantaneously, idles high and drops when hot, no codes, shutter valve free, no ticking from shutter valve actuator, engine has 21,000 miles on it, BHR ignition and premium every tank. I may have left something out, but this is the base line. I have searched the forum and cannot find the root cause.

Help, it is aggravating me! Thank you in advance!

Are you sure you overfilled it with oil or did you just assume? Oil in the intake could also be from excessive blow by meaning a failing engine. Was it running fine before?

I am absolutely sure I used a 5 quart container thinking it was a 4 quart container when I filled the engine on my oil change. I am also sure when I drained it I measured 4.X quarts that came out, not including the mess I cleaned from the intake. I refilled it with 3.8 quarts and cleaned all of the above mentioned. I am sure I have no internal engine issues. It runs like a bat out of hell when I ask it to, it starts up immediately both cold and hot, it idles smoothly with the exception of the motor mount vibration and there are no other symptoms that indicate engine issues other than I have outlined.

I twisted it up between 7 - 9 k for an extended amount of time through multiple passes and then it choked and smoke came out like it was on fire. I removed the intake tube and found oil every where. I did this a couple days after I changed the oil and checked the oil container I used to fill and realized my mistake.

Thank you for the comment and please keep them coming. I don't want to turn wrenches or start hanging parts on it without a root cause. I have enough rabbit trails to go down at work. :yesnod:

https://www.youtube.com/watch?v=GfpZg15sIkk&feature=share

There is no telling how much oil made it back into the intake tract and how far revving it to redline with an extra 1.5QTS. It possibly made it into the vacuum solenoids, purge valve, etc. I would remove the UIM and make sure everything is clear of oil.

In the future, I'd suggest adding only 3.5 quarts at most and then checking the level after running the engine for a bit. 4 quarts is even too much. The manual recommends only 3.5QTS if you are not changing the filter and 3.7QTS if you are. I use an extractor and barely get 4QTS out, no way you are getting 4 with a standard drain.

Thanks, I'll look into your suggestion on the Uim and a good point. I am sure I will find residue. I agree on the oil, however I can extract 4+ quarts out when 4+ quarts went in. I generally put 3.8 as my original manual lists as I always change the filter. The filter holds an amount, so measuring the drained oil is always less than 3.8 quarts.

The mike on my iphone did not pick up the audio. The shuttering sounds like multiple rapid misfires when the rpm drops in the video.

Sorry, my VW is 3.8 quarts, the RX8 is 3.7 quarts. I have always added judging approx 1/4 left in a 4 quart container. I will use your suggestion of 3.5 quarts, start engine for a bit then read after it levels off.