Octane Boost question??

[FiveO]

So as far as I can tell, the U7194 programmer for my 2009 Sierra 5.3l (provided its even compatable with my "M code" engine? ...see other post "anyone running a DS on a "M" code ...") has a 87 octane and a 93 octane tune.

I live in Alaska, and the highest pump octane available is 90 (aint that some shit!). So if I wanted to use the "93 octane tune" would it be acceptable to use aftemarket octane boost in my tank when I fill up? If so, does anyone have an easy method for calculating how much boost additive to use per tank to get me to 93 octane or better?

If I'm running the "87 octane tune" ...would it be any more benificial to run 88.5 or 90 octane pump gas to get more from the "87 tune", or am I just spending extra money on gas for no reason?

Do I need to "adjust" the performance tune (wether its the 87 or 93 octane tune) during the winter months? I've seen a little conversation on this in the threads, but uncertain? Which parameters to "re-tune" for colder weather?

Appreciate any replies. Had the Diablo Sport on my 7.3l Power Stroke ...smoke'n tune!! Never need to mess with it ...just load and go! But this new 09 Sierra with the gas motor seems way more complex ...trying to squeeze every ounce of horspower I suppose.

Thanks!

[06MonteSS]

octane boosters do not raise your octane by that much.... you'd go from 90 octane to about 90.4 or 90.6 octane.... still not enough to run the diablo/performance 93 octane tune...

so if you use the diablo/performance 93 octane tune, you'd need to go into the spark advance settings for each rpm range, and pull out about -10% of spark advance... or, if you have a newer revision (9r08 or higher), then your spark advance settings will be in actual degrees instead of a %, so pull out about -2 or -3*....

[08chev]

you can ook into toluene as an ocatne booster. i use in my 08 to get ride of kr. works great. i mix about it to 10% to take 91 to 93. to "over the counter" boosters didn't do anything for me and they say MMT is hard on 02's and cats... toluene is used at the fuel refinery to increase octane... i just mix more in. its not creap ($50 for 5 gal. at the paint store) but like you i can't buy 93 so if i want the tune i dont have a choice.

[FiveO]

Thanks MonteSS ...thats what I needed to know.

08chev ...thanks for the reply Dude, but I don't think I'll be pouring anything from the paintshop into the fuel system of my new Sierra. Maybe if I were a Chemical Engineer I'd feel better aboout that! LOL!