Radiator air flow

[driveslikejehu]

When I finally fitted up the radiator floor panel, I realized the only air to the radiator is thru the top opening in the bumper. Shown in yellow.
front bumper 2.jpg

This is about 79 sq.in. Is this why the hood vents seem so small? They add to about 92 sq.in. These openings seems small compared to the size of the radiator.
It seems possible to space the radiator floor down and use both openings. Is anybody doing that? If you run a splitter, do both openings go to the radiator?
Am I over thinking it?

[J R Jones]

What other thermal load do you have?
It looks like your car is an R model, for track duty? So no air conditioning.
Are you running a AWIC core in front of the radiator?
How much power are you dealing with?
Shrouding is effective but disputed by some forum members.
It looks like there is a void between your splitter lip and the panel below your radiator that will by-pass the radiator core.
Your temperature gauge is the final arbiter.
jim

[lance corsi]

I’m running a splitter and my grille openings are more generous than yours. I’m utilizing the entirety of the grille (except the outer perimeter and the other whoopteedos ). All goes through the rad and the ic rad. I’ve got hood louvers to exhaust the air, as well as the gap between the hood and windshield. Some rads have a shroud which covers the entire core, except for the cutouts for fans, plus maybe a couple small pass-thru flaps for passive airflow. On mine, I’ve cut the shroud down to only a bracket to support the fan, the rest is open. This allows much more passive airflow than the full shroud. Btw, I used a bulb seal to seal the fan shroud to the rad core.

[Hobby Racer]

It seems possible to space the radiator floor down and use both openings. Is anybody doing that? If you run a splitter, do both openings go to the radiator?
Am I over thinking it?

I run an R with a larger front splitter and yes, BOTH openings go into the radiator. I highly recommend fully ducting the air to the radiator AND ducting it out the hood vents. If you do not duct the exiting air it creates a high pressure area behind the radiator and reduces the air flow through the radiator.

[Ford & Jeep Fan]

I saw something years ago (I lived in Daytona beach at the time) that the super speedway (NASCAR) teams found that a grill opening 1/6 the square area of the radiator was the best for cooling AND running the smallest opening possible.

[Rob T]

Mine is the Same as Hobby and ducted to the radiator. AWIC is in front. I also added some nomex honeycomb about 1/2 thick on the radiator or your AWIC radiator will get shelled with track debris. Cooling on hot days was a bit of a problem, but not an issue now that my oil temps are under control (3 stage scavenge system and a few coolers).

[Hobby Racer]

Mine is the Same as Hobby and ducted to the radiator. AWIC is in front. I also added some nomex honeycomb about 1/2 thick on the radiator or your AWIC radiator will get shelled with track debris. Cooling on hot days was a bit of a problem, but not an issue now that my oil temps are under control (3 stage scavenge system and a few coolers).

I forgot to mention that my setup is just like Rob's, AWIC radiator in front and 1/2" honeycomb protective barrier in front of that and no issues with temps.