vented BRZ fender trim?!

[Yoshoobaroo]

Originally Posted by ThatYeti

Interested as well, though in less apt to be cutting the metal behind it unless the cooling benefits are significant

It does, there is barely a slot 1/8” wide without cutting.

[Ernest72]

I bought used fender garnish to experiment with. I would love to just slot the stock black trim and cut the back out first. Worse case if it does not look good I can cut it out and put in a new grill. Then I need to match the cuts on the fender. Once I get it, I will start some planning. Any ideas or input?

[ThatYeti]

Originally Posted by Ernest72

I bought used fender garnish to experiment with. I would love to just slot the stock black trim and cut the back out first. Worse case if it does not look good I can cut it out and put in a new grill. Then I need to match the cuts on the fender. Once I get it, I will start some planning. Any ideas or input?

I'm a little concerned opening this up at all will necessitate adding something stronger than 3M tape to hold it on given it's going to be dealing with air pushing out. Love the idea of making them any kind of functional though as fake vents are a real pet peeve of mine.

[Ernest72]

Originally Posted by ThatYeti

I'm a little concerned opening this up at all will necessitate adding something stronger than 3M tape to hold it on given it's going to be dealing with air pushing out. Love the idea of making them any kind of functional though as fake vents are a real pet peeve of mine.

Totally agree. At a first quick look, I would just be looking to remove fender material in between the clip mounting points. Then the tape is added as a secondary. I am going to focus on the garnishes first and what I will do to them. Once I have that idea, I can see how the holes I have made can match up with the fender.

[ThatYeti]

Originally Posted by Ernest72

Totally agree. At a first quick look, I would just be looking to remove fender material in between the clip mounting points. Then the tape is added as a secondary. I am going to focus on the garnishes first and what I will do to them. Once I have that idea, I can see how the holes I have made can match up with the fender.

Maybe using something similar to a brake duct to direct air to the vents so as to provide better cooling an potentially alleviate the pressure against the 'body' of the garnish

[RayRay88]

Originally Posted by ThatYeti

I'm a little concerned opening this up at all will necessitate adding something stronger than 3M tape to hold it on given it's going to be dealing with air pushing out. Love the idea of making them any kind of functional though as fake vents are a real pet peeve of mine.

Air isn't being "pushed out", it's a low pressure region, so technically sucked out. It'll see way less force than a spoiler and that is able to withstand adhesion with just adhesive tape. I wouldn't overthink it. Just make sure the surface is prepped properly and the tape is of good quality.

[dragoontwo]

Originally Posted by RayRay88

Air isn't being "pushed out", it's a low pressure region, so technically sucked out. It'll see way less force than a spoiler and that is able to withstand adhesion with just adhesive tape. I wouldn't overthink it. Just make sure the surface is prepped properly and the tape is of good quality.

I'm not an aero expert, but at interstate and above speeds wouldn't it become pressurized? The intent is to vent from the engine compartment correct? On a stock car, there is significant pressure in the engine bay that causes the hood to deflect upward at higher speeds.

[ThatYeti]

Originally Posted by dragoontwo

I'm not an aero expert, but at interstate and above speeds wouldn't it become pressurized? The intent is to vent from the engine compartment correct? On a stock car, there is significant pressure in the engine bay that causes the hood to deflect upward at higher speeds.

This is exactly what I was thinking, as everytime i'm on the highway I get uneasy when I see the hood floating up a tiny bit

[RayRay88]

Originally Posted by dragoontwo

I'm not an aero expert, but at interstate and above speeds wouldn't it become pressurized? The intent is to vent from the engine compartment correct? On a stock car, there is significant pressure in the engine bay that causes the hood to deflect upward at higher speeds.

Yes it's "pressurized" but it's not as simple as that. The vents will provide some release but it won't fully release the high pressure zone through the side vents the same way hood vents will. Also speaking of hood vents threes a reason they need to be in a particular area in the car to maintain effectiveness. They need to vent in a low pressure region otherwise they would intake vs exhaust. Wicker bills also aid in creating a larger low pressure region to increase their effectiveness. The fender vents will only flow whatever the low pressure region around it will support.

The stock hood is just flimsy aluminum, you're talking about a larger surface area for the pressures to act on. Hence the death rattle.

[Wally86]

Originally Posted by RayRay88

Yes it's "pressurized" but it's not as simple as that. The vents will provide some release but it won't fully release the high pressure zone through the side vents the same way hood vents will. Also speaking of hood vents threes a reason they need to be in a particular area in the car to maintain effectiveness. They need to vent in a low pressure region otherwise they would intake vs exhaust. Wicker bills also aid in creating a larger low pressure region to increase their effectiveness. The fender vents will only flow whatever the low pressure region around it will support.

The stock hood is just flimsy aluminum, you're talking about a larger surface area for the pressures to act on. Hence the death rattle.

I've been following this thread because functional vents would be baller, of course BUT

I had no idea the hood shaking at highway speeds had a name. I've noticed that over the last 1.5 months ownership and I've thought that maybe the play in the hinge or something needs to be adjusted LOL.

Death Rattle.

[Ernest72]

My concern is to do this correct, because years ago on the NAsioc forum, I remember someone doing similar things to reduce under hood temps. One finding was that it effectEd the flow over the radiator negatively which is something you don’t want to do unless it’s more flow. I can’t remember what the modification was. I will do some searching of the internet. My feeling is holes in the right place is good, holes in the wrong place is neutral to bad. I don’t want to do this much modification for a DD just because Racecar.

[RayRay88]

Originally Posted by Ernest72

My concern is to do this correct, because years ago on the NAsioc forum, I remember someone doing similar things to reduce under hood temps. One finding was that it effectEd the flow over the radiator negatively which is something you don’t want to do unless it’s more flow. I can’t remember what the modification was. I will do some searching of the internet. My feeling is holes in the right place is good, holes in the wrong place is neutral to bad. I don’t want to do this much modification for a DD just because Racecar.

I think it's best not to overthink this, it's going to help but don't expect jet streams of hot air to shoot out of these vents or a drastic reduction of under hood pressure/temps. You won't see that without large venting.

[Yoshoobaroo]

I did this 2 years ago. Hot air POURS out of them when the engine fans are running. at speed it must be even more.

3M tape is holding them on just fine. Keep in mind that venting the pressure reduces the force imparted on the trim piece.

[ThatYeti]

Originally Posted by Yoshoobaroo

I did this 2 years ago. Hot air POURS out of them when the engine fans are running. at speed it must be even more.

3M tape is holding them on just fine. Keep in mind that venting the pressure reduces the force imparted on the trim piece.

Did you cut out any additional metal from the inner fenders?