Accidentally put 87 in the REX
 

That bad and what do I do with a full tank of it now? Wasn't paying attention when I was pumping gas until about a third of the way through fueling.

I'm at 90K on my original '04 engine, been using 87 octane pretty much since day one. Don't worry about it, just drive the car.

Just "enjoy" a little less performance, and don't repeat. That's pretty much what my manual reads.

Yeah, I also almost always use 87. So, unless you experience problems, nothing to worry about.

Well I haven't noticed any difference but I just wanted to make sure I was going to cause severe engine damage like the manual states even though manuals like to over exaggerate things sometimes.

you'll probably notice the difference when you go back to premium. I can certainly tell a difference in the performance between 89 and 93.

But not a problem my engine won't blow up or some crazy shit? Thats all I want to know

You should be okay. I did that the first time I got my 8, and nothing happened.

I did it once in my 05 couple years back, it made the marbles in a can sound and I've never used anything but 93 since. Little powerloss but you should be ok.

I seriously don't think so. My manual reads that you will likely experience a loss in performance at lower octane. If it could cause serious engine damage, I'd think it would be page 1 in red. You're gonna be okay.

On the factory tune there is no knock detected, so it does not add fuel or pull timing in either leading or trailing plug based on either 87 or 93 octane.

I can run 87 in the fall and winter when it's in the sixties. If your fuel is too low in octane the Rotary will let you know. Keep your Bose lower so you can listen for a new sound from your engine. If you do hear a new sound from your engine(when asking for more power) back off the throttle. Take it easy on this tank till its down at least half way before filling with prem. You don't want to push your car and hear the MIAC (Marbles In A Can) pre-ignition sound of a Rotary engine. It is very damaging!

I'm sorry, where in the manual does it state anything about severe engine damage with 87 octane gasoline?

I agree woth OR, take it easy while using the lower octain as it can't stand up to the hotter temps. as well as the higher octaine. Or, you can just put a can of octaine booster in your tank ;-)

you should be fine just dont do it again