[ZLRob]

Originally Posted by TurboC3

This is similar to my, currently 93oct, under warranty plan. Stage 1..x-port & 107tb, no tune. Stage 2..add a lower pulley, E85 and a tune. Is this a good plan? Don't want headers, trying to keep it as stock as possible...lol.

Not a good plan. You do not change any airflow characteristics on this vehicle without needing to compensate for it within the calibration file itself. You will either be losing power from going lean, and/ or creating knock which will rob you of power due to timing pull, which is dangerous due to the fact that if you do it a lot you can grenade the engine despite forged internals in the LT4, so you'll either be making the same or quite possibly even less than what you make right now despite the extra mods. Just to give you an idea, despite all of my mods, I still only make 585 on 91 octane fueling (it's the most available fuel around where I am) and then as soon as I fill it up with pump E85 I go all the way up to 758, which is absolutely stupid from a power delivery standpoint, but those are the limitations of the standard gasoline fueling where I am. Is what it is I suppose.


Save yourself the trouble and get the mods you want on it, then tune for it. Just know if you do a pulley, a ported blower, and try to run E85 on it you will definitely not be able to run pump.


The mods in my signature, they're not on accident or just because I wanted extra fueling headroom. I was forced into it because in order to run ethanol the fuel system demands at least 30% more fueling over standard octane gasoline.