Oh, so now im going to have to mod to INCREASE my IATs?
Jk.... they're high enough.
I dont even want to know what it'd be on these 100+ degree days @ 50%+ humidity after a 1/4 mile pull. Its about 130 degrees peak when its 80 degrees ambient.
Im kidding about all that though.
However, im curious about the benefits of IATs on a PD vs centri. I've read that IATs are meaningless on a PD below a certain point. Ill just summarize to say that whatever IAT temp puts you below "knock thresholds" (hand wave)... because cooling down the air charge after the rotors CAN'T add any additional air MASS to the charge because of the nature of a positive displacement pump. A set VOLUME of air will pass the rotors depending on the physical characteristics of the PD. Whatever you do, that quantity of air will never change regardless of what you do to heat or cool it.
Only thing super low IATs could do in PD is decrease boost pressure by cooling, thus shrinking the air VOLUME (not to be confused with air MASS) after it has passed the rotors. In same way, decreasing the boost in this way ALSO has no effect because its always going to be the same air *mass* aka same quantity of air regardless of what you do to it after it has passed the rotors.
Now on a centri, not sure that holds up. Cooling the air charge, thus making it denser, supposedly has continued benefits on a centri the lower you go because it is not a positive displacement pump. Densifying (by cooling) the air after it passes a centri supercharger will allow higher air mass to enter the cylinder.
This is just what I've heard/read, not necessarily saying any of that is hard fact. Plus typing this out on my tablet, so hopefully that was all coherent.
To summarize, my question is... on a PD, if your IATs are already below the threshold where you need to pull timing, whats the benefit of going even lower on IATs, because once you pass the rotors, the quantity of air that enters the cylinders is the same regardless of temp.
AND does this work differently on a centri (and turbo too)?
Sorry, not trying to hijack thread, but the original question was about meth for cooling on a centri, and im unclear about whether there would still be a benefit for OP to add meth for cooling which occurs AFTER the air compression occurs for a centri.