...since you will likely be running an aftermarket PCM, those do usually require 93

 

I run 87 in my NA 3800 impala, and 93/94 in my SC 3800 grand prix / monte (although the monte has had some 100 unleaded in it a couple times)


Thats because they add more spark advance. If you run regular fuel, it will knock (the pcm will respond and pull timing back out)- and you end up negating a lot of the gain with a tuned pcm on a NA application.

Octane booster is a waste. If the best you can find is 91; and you're doing a top swap; you'll need to get a ZZP 4.2" pulley (makes the top swap a bit easier too since you won't have to pull the crank pulley)- and also possibly add a handful of mods.

 

you are correct bumpin. octane boost does NOT work. it is pretty much a sham so don't waste the money. the only way you can change the octane rating is during the refining process, period. if you can't get 93 in your area, a top swap or aftermarket PCM may not be the right thing for you.

 

Well that sucks, Ill have to prowl nearby towns for 93+.... prob be a shell station.

 

Well, unfortunately, I let my friend talk me into putting premium in my car before I had the chance to get on here and look at everyone's responses. On a quick side note, I have the hypertech programmer and it recommends premium... However, when we put premium in it, I almost immediately noticed that my monte kind of "shutters" when you have the foot steady on the gas pedal... at first it did it every now and then, but I got in my car after a 36 straight hour shift, ready to take my hour and a half ride home, and it gave me problems the whole way. There were a couple points where I thought it was going to stall out when I came to a complete stop, it would just idle real rough. And still when Im driving it kind of bogs down a little... I dunno what it is... I just cant win!