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When I look on either side of my front Pontiac symbol, at the two inlets in the front bumper of the GXP...
Nearly 30% of the possible airflow stream through those inlets is actually blocked by black styrofoam... the bottom 30%.
Seeing as any opening in the front of a car is an airflow disruptor, which increases drag and lowers speed, and it's already 30% closed anyway... what benefit would there be in closing up completely the two iconic Pontiac grills?
Good idea? or?
Mathematically aerodynamics would be better I don't think anyone can dispute that... that's a pretty major wind tunnel mod blocking those grills... possibly the most beneficial of all(I'm also looking at adding skirting underneath where possible)
But would the cooling system at all be taxed by closing it up? And if so who cares it's not like I won't know when the car needs to cool down because I have all the temp gauges through the Torque Android app...
I've already redirected my front license plate up higher towards the top grills (it's law here to have a front plate) in order to allow the intercooler down below better airflow(plate was blocking airflow)... THAT's the thing I want to get cool air to the intercooler... Plus.. would love to hear some ideas on how I could maybe semi easily find or fabricate some kind of front lower air dam... the bottom of the bumper on the GXP can be reinforced on the inside with a plate, then an air dam secured to it rigidly...directing airflow to the sides of the car and more importantly increase air speed under the car...
First I have to say I didn't read that article you linked to, but removing the only real source for fresh air to the radiator or engine compartment would in my opinion not be a wise move. Race cars are purpose vehicles , and as such do no apply to the rules of the road as any street car would, highly modified or not. I do not know if your car has a functional ram air hood, but heat is this cars worst enemy already so blocking off fresh air entering the engine compartment would make things much worse. I am sure removing that front bumper you could probably remove some material in places to enhance flow, but then you might lose some structural integrity. Anything can be accomplished with time and money, so you have to figure out exactly the direction you are heading with this car. Cars designed for high speed and top end runs like you would find in a car prepped for the Silver State runs are set up totally different from a car running the quarter mile. Another thing to consider is this car is a heavy sedan, and at the end of the day every trick of the trade to achieve some sort of supremacy will most likely fall short against cars with a bigger parts aftermarket or are more aerodynamic to begin with. This is a fantastic read of what car be accomplished with fat pockets.
One last thing, if it was me and I invested in all the modifications to the engine /transmission/vehicle as you have I would not rely on any Torque app for real time engine specs. A good quality set of gauges can not only be helpful in diagnostics, but also eye candy if installed correctly. Pic complements of Spawne
Actually, you bring up a lot of good points which has changed my mind mostly about what I'm going to do... especially the point about cooling...
And as it stands now, I am not interested in TOP SPEED numbers at all. I've been as fast as 262 KPH in my car and I don't want to push major HP through the 4th gear as I've been advised by Cartuning that 4th gear is really a fuel economy/highway gear not something to push 600+ HP through trying to get to 300kph or something even though that would be a cool video to have... and as to your other point, better 1/4 mile times have much more to do with driving and traction management rather than aerodynamics anyway.
I still am going to add diffusers though, and more skirting underneath because I think there is definitely room for improving airflow underneath the car... speeding up the air and getting it out the back... very important.
Here is a couple questions though...
1) what do you think about using those two openings on the front lower bumper underneath the forward facing turn signals... build some type of channel/duct that redirects some airflow up into the engine area? As it stands now those openings are not being utilized at all aside from looks...
2) Why is torque not good compared to say the Aeroforce from the pic you posted... both hook up via OBD2 and get their information from the same place... no?
The gauge pictured was just an example installed, I have no experience with that model or how it hooks up. Mechanical gauges plumbed thru oil port, vacuum or water is more what I was referring to. I have the Torque app also, not sure if that is true readings but I would think people who spend big dollars on their upgraded drivetrain mods probably are not relying on it. As I said anything can be accomplished either by how good your crafting skills are or how deep your wallet goes. Those ports could be utilized, but they are very small. One option would be to look into replacing the bumper with a 2004 GTP models, it has much more open area to create something. Or fabricate something like this, but route it for fresh air to the engine compartment instead.
I am no engineer, but that could possibly cause issues so a ram air hood should still be considered to help with those temps.
10-18-2016, 12:35 AM
reduce drag/optimize airflow 
Pontiac grills?
