Definitely super clean Dave!
Gents - I apologize.. I think we're getting lost in the weeds here. It doesn't help that I used a misleading picture to illustrate my point! Agree that this shrouded setup (with the gaps on the side) would not work and like you said.. the air will get sucked in from the sides instead of thru the core.
The copper/brass radiator Jim and I are using now has a denser fin configuration than the Aluminum rads I've seen including the OEM. The denser configuration allows for better cooling capacity at the expense of requiring slightly better airflow (at stop/go traffic conditions). It's difficult to provide you guys with a comprehensive set of data because there's a lot of different configurations to test for. Not to mention it's already winter and some of these conditions can't be tested for (i.e. 100F+ LA traffic stop/go conditions where the 1 fan, no shroud configuration failed me with a stock non-vented hood)
With that said, we've tested in so many conditions already that Jim and I are already looking beyond our cooling problem of past. The MASiV radiator works for us and it's the OEM size.
Here's are the conditions we test for.
Car 1 - Jim's 500+wHP turbo, Laminova Oil Cooler, Front mount Intercooler with MASiV V3 Radiator. Tested on the track in AZ and CA. Tested on the streets and fwy.
Vented and ducted hood
* OEM shrouded fan (does not work)
* Two Mishimoto fans with the Dali Shroud (did not work with V2, haven't tested on V3)
* Two Spal Fans (ideal setup for Jim due to his high HP)
Car 2 - My car ~360+wHP CTSC, water injected, side mount oil cooler with MASiV V3 Radiator. Tested on the track in CA. Tested on the streets and heavy LA fwy stop/go traffic.
Type R style Vented hood
* OEM shrouded fan (works fine)
* OEM shrouded Spal Fan (also works at the track)
* Single Spal, no shroud (this might work because the vented hood will allow enough low pressure air behind the rad. Have not tried it)
* Two Spal Fans, no shroud (have yet to try this but we already know it works in Jim's car)
OEM non-vented hood
* OEM shrouded fan (works at the track at track speeds but I experienced slightly longer cool down times, not alarming because as I pulled into the paddock ECT was 82C but as I was pulling into my stall it climbed to 90C+. I had to do a slow lap around the parking lot and it got back down to 79C before I turned off the car. As Jim mentioned it cools down fast enough)
* OEM shrouded Spal Fan (also works on/off the track, my best configuration so far for all conditions)
* Single Spal, no shroud (have not tried this yet but I hypothesize it might not work in stop/go LA traffic because the MASiV is a denser core rad and requires more airflow in stop/go conditions. Without the additional low pressure venting of a vented hood I believe the air flow will suffer. I hypothesized with Billy that if this was a side-to-side flowing rad that it would work with this fan config but it won't work with a top-bottom flowing rad)
* Two Spal Fans, no shroud (have yet to try this)
Hope this helps illustrate that there are a lot of conditions to test for. Happy to hear your thoughts!
p.s. I forgot to mention that I have two slim Mishimoto fans. They are really mediocre fans but they are slim and draw very little current. I will try this fan config with no shroud soon. I think it will work with the MASiV V3 because the fin design is more optimized for air flow.
