What would be the effect of using the programmer on level 3 but still just using 87 octane?

 

Detonation. Bad idea. Run the 87 darn near dry and fill with high octane.

 

That would be a VERY VERY VERY bad idea.

 

Bad idea. BAd, BAD!

 

thanks fellows

 

I tried it (by accident) for about a quarter of a tank. Never heard any predetonation. Makes me wonder if the gas is not better than the rated 87 it says. That was with a few WOTs. I have been running 93 and really can't tell any difference from when I was running the 87. Not brave enough to do it all the time though.