Go with the LS1... the 7M-GE will net you dick... even with high comp and NOS. The only CO2 systems I've seen are used to cool intercoolers in order to compensate for the extreme increase in air temps due to compression from turbo and s/c setups... it's not sprayed into the intake nor does a N/A have enough surface area in the intake tract to reduce air temps enough to make any real difference. Actually spraying inert gasses such as CO2 INTO the intake on a relatively low displacement and low compression (even with off the shelf higher compression pistons) engine like the 7M is more likely to cost you power than gain any.
I know a few people who've spent absolute fortunes on the GE only to abandon the project or settle with the fact that they'll never see the numbers a mildly modded GTE will get. I was like you... had BIG plans for the GE... now I run a turbo.
An IAT isn't really needed with a GM MAF... do you mean IAT and MAP sensors? It's referred to as Speed/Density. FYI, a MAF measures actual air flow whereas with s/d it's calculated.... s/d can be a bit tricky to get running smoothly but imposes no restrictions on the intake.
I ran high comp and s/d on a very well tuned 7M-GE... still didn't dyno past 200RWHP... Just reaching 200RWHP on the 7M-GE is quite difficult. If you want some more negative commentary on the lacking potential of the 7M-GE from those who have tried it head over to supramania and search the 7M-GE section for "potential" (might as well just search "irony"). Then look up build info from members including "Defiant7M" and "AJ's 88". For 1/10th the cost you can achieve more power with a forced induction setup. Sorry, but that's just the way it is. On the upside, at least you don't have a 1G-GE.
