Having the ambient posted for each data collection bin would be very helpful b/c I'm convinced that it comes into play w/r to the delta IAT to amb i.e. at 100 deg ambient the same IC will show a higher delta vs. that IC at 50 deg amb but as always....have to have data to back that hypothesis.
For IC temps only, ambient is almost irrelevant as far as I can tell for the way I'm taking logs (on track - it definitely seems to affect the ability sitting still/in traffic etc). It's 100% relevant for coolant temps though.
Look at
@MonkeyMD 's logs... his 107F log shows a couple deg lower IAT delta vs the 88F ambient log.
Compare all #2-5 of mine: They range in ambients from 48F-90F. The "worst" of the DO88 was on stock tune in 48F ambient.
I don't think there's a strong enough correlation between IAT deltas and ambient temps to really matter. There's going to be more variance from session to session or track to track than anything. Hell - look at #4 and 5. Same day with a little over a 2F average difference.
Like I've stated before: None of these should be taken as "absolutes" to declare X is better than Y. The honest truth is that anything to the left of the stock intercoolers will all perform within noise of each other. You'll likely never notice a 5F difference on the street - where ALL of the above [aftermarket] intercoolers will perform BETTER because they won't be seeing WOT for 15-20 minutes at a time.
IMO the track makes the stock intercoolers look a LOT better than how they actually perform on the street. You'll see super high IATs from heat soak at lights, and they shed *some* heat quickly but if you're running more boost or bigger turbo they quickly heat up fast, and then there's the internal flow restriction/pressure drop aspect as well which is better covered on Jeff's page.
