Increasing air flow through grill

[Paul McWhiskey]

OK, since my Harrop oil cooler arrived last Friday, I have been marinating on this. While I have things apart for installation, why not do something with radiator ducting? My thinking is that if I increase the pressure in front of the radiator it will also increase on the oil cooler causing more airflow through both. Increased airflow should equate to increased cooling. However, with a stock hood will I also be increasing drag and lift? Also, what effect will the air going through the cooler have underneath the car?

I know, I know, some probably think that I am way overthinking this. The primary reason for the oil cooler is for track cooling. But making a change on one thing most always causes changes elsewhere. I would be especially interested in what those that have installed the Harrop and use the car on track have to say, but any well-reasoned replies are appreciated.

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[Rapid Red]

I recently acquired a 2019 PP2. I noticed that the small area of the grill that the engine air in take ( drivers side) sits behind has a few hexagon shape opening open but also has some of the hexagon shaped closed from the factory, filled with plastic.
any ideas why all those would not be open?
The passenger side seems to have all of these shapes closed/filled. Seems for a track car it may be worth while to open them up with a dremel to allow for more air flow.
We did that with the 2012 Boss faux round lights in the grill when the Boss was having high temp issues on track.
Sorry if this has already been addressed, if so please point me in the right direction

Seriously, have my doubts as to any measurable performance gain to be found.

As a DD can see scooping up more trash & bugs.

 

[Jstang23]

Several tuners have told me the stock air-box is actually very good. Its completely sealed so the IAT stay pretty low. Unless you're building your engine pretty significantly I don't think cutting out the front grille hexagons is going to do anything.

 

[monte87]

The gt500 has bigger grill openings I’m pretty sure. The best reason to open the grill is to force more air through the radiator at speed, not the air intake.

Maybe I should do this…

Edit: GT500 pics suggest mainly the lower grill is opened up.

people also forget its open for cooling......... air at speed cools the engine bay, Big time.

 

[NightmareMoon]

airflow isn't really all that intuitive. more exposure to the air doesn't do what you might intuitively think for radiator performance.

We want to maximize pressure at the radiator, which actually means slowing the air down by ramping from a small inlet to a big radiator face. This is why the grill openings are a fraction of the size of the radiator core. (usually 20-40% of the core size). It also depends on the radiator for what pressure drop they work best at.

This is a good video if you want to get some info on the engineering.

 

[Dana Pants]

There is no room in the front of a car to have any approximation of an expander. Just gobble air with the biggest mouth possible.

 

[YULQQKN4]

i recently installed the Cervinis grill and velossa intakes and notice a great cooling effect on IAT's and block temps. IATS's are constantly within 1-2 degress of ambient temps at speed

 

[Bossdog]

airflow isn't really all that intuitive. more exposure to the air doesn't do what you might intuitively think for radiator performance.

We want to maximize pressure at the radiator, which actually means slowing the air down by ramping from a small inlet to a big radiator face. This is why the grill openings are a fraction of the size of the radiator core. (usually 20-40% of the core size). It also depends on the radiator for what pressure drop they work best at.

This is a good video if you want to get some info on the engineering.

very interesting video! That’s why Shmoe’s like me modifying anything on my car is more likely to have a negative impact, than anything else. Even young inexperienced engineers at the OEM’s have all the previous experience or their predecessors to guide them.

however, for all the accolades the std GT air box gets, the GT 350 and Mach 1 have the open air box. Is that just for show?

 

[illadvised]

I was under the impression that you want to force air through the center of the radiator. If you open up more of the grill, it's more likely that air can go around/under/over the radiator.

I did something similar on my 3 valve by opening up more of the grille, and it was enough air into the engine bay that it ripped my splash guard off of the bottom. And it did not help temps at all. Basically it made the front of my car a parachute instead of forcing air through the rad

 

[WItoTX]

I was under the impression that you want to force air through the center of the radiator. If you open up more of the grill, it's more likely that air can go around/under/over the radiator.

I did something similar on my 3 valve by opening up more of the grille, and it was enough air into the engine bay that it ripped my splash guard off of the bottom. And it did not help temps at all. Basically it made the front of my car a parachute instead of forcing air through the rad

The key is ducting the air through the grill, through and around the radiator, and up through the hood at the low pressure bubble. Otherwise it's all just a wash at best, and likely a cooling performance downgrade.

 

[NightmareMoon]

very interesting video! That’s why Shmoe’s like me modifying anything on my car is more likely to have a negative impact, than anything else. Even young inexperienced engineers at the OEM’s have all the previous experience or their predecessors to guide them.

however, for all the accolades the std GT air box gets, the GT 350 and Mach 1 have the open air box. Is that just for show?

Well, IDK. The newest stock airboxes have a restrictive piece that you can remove and after that they flow just as well as the 18+ airboxes which were great. (its the reason the hp numbers dropped a smidge). On the 15-17s, the lower part of the airbox which feeds from the grill isn't really the issue, it was the stuff after the filter which was restrictive on the 15-17s. Steeda's closed airbox reuses the stock lower stuff on my 16 and flows a ton better (like 20hp better with a tune), but then the MAF signal quality isn't great with that specific setup unless you take additional steps.

The open airboxes look fast, but they're sucking in more hot air, which is the issue (mostly from a stop or when heat soaked). They probably add a bunch of audible intake noise which makes them appealing on the 350/Mach 1? I'm guessing here, but I we do know the closed '18 intakes flow great. Could be they just needed 'something' different to claim the car is improved over the stock models, or maybe they do flow a couple horsepower more at the top of the rev range, IDK. Its doesn't seem to be a big factor. The different filter design is probably a slight advantage over the stock filter, but probably not a noticeable advantage over a K&N replacement panel filter in an otherwise stock closed intake.

 

[NightmareMoon]

I was under the impression that you want to force air through the center of the radiator. If you open up more of the grill, it's more likely that air can go around/under/over the radiator.

I did something similar on my 3 valve by opening up more of the grille, and it was enough air into the engine bay that it ripped my splash guard off of the bottom. And it did not help temps at all. Basically it made the front of my car a parachute instead of forcing air through the rad

Right, that video touches on the fact that where you're samping the air from matters. Not all regions of air are equally good based on the specific bumper/front end aero, so if you're opening things up, you're pulling in air from some of these bad regions too, which may be a little detrimental.

 

[TX-2019-Black_GT]

Yeah I sanded from the back when I added the big mouth :

WD

I also opened mine from the back, but how did you get the grille separated from the bumper? I thought it was a one-way snap in, but I didn't try too hard to figure it out.

 

[ice445]

very interesting video! That’s why Shmoe’s like me modifying anything on my car is more likely to have a negative impact, than anything else. Even young inexperienced engineers at the OEM’s have all the previous experience or their predecessors to guide them.

however, for all the accolades the std GT air box gets, the GT 350 and Mach 1 have the open air box. Is that just for show?

The open airbox does flow better at high rpm, that's how the bullitt/Mach 1 gets the 20 extra hp bump over the normal model (well, that and the larger throttle body and gt350 intake). The cone filter allows more air without sacrificing filtering quality, so that's why they do it.

 

[stannypack]

found this interesting

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