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Discussion Starter #1
If I keep it off will it heat up engine or damage anything? Sounds better off I prefer off actualy
 

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You mean if I close it?
Take hood liner off it will sound good lid off or on.Take cowel seal off if you want to hear max sound.I have had engine cover and hood liner off for 2 yrs.+. Would put back on only to sell car.I did put cowel seal back on.
 

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Discussion Starter #5
Take hood liner off it will sound good lid off or on.Take cowel seal off if you want to hear max sound.I have had engine cover and hood liner off for 2 yrs.+. Would put back on only to sell car.I did put cowel seal back on.
Perfect aswome this convinced me to keep it off wich I already did amd drove 30km so amzing trottle response increased alot car dosent hesitate anymore. Also clunging noise from 2nd gear gone
 

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You mean if I close it?
No if you leave it off it will run hotter. Also the open ended type filters have the potential to increase IAT more than stock or closed end style filters. Same goes for leaving the air box lid off. Plenty of people do it though, nothing will break, it’s just not technically the best solution.


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Leaving off can suck in hotter air as opposed to closing the air box. You'll also lose some pressure from keeping the lid off.

Really minimal, and more so just a personal preference.
 

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But only if you use the RS airbox lid. If you're driving without a lid on, it won't seal anything, hood liner on or off.
 

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To answer your question, no, you are not going to damage anything. The car will compensate for whatever small changes it sees from running the lid or not. If you have an AP, go do some pulls and log with and without. I really dont think you will see anything significant, less so if you have an aftermarket intercooler.

I dont think the under the hood temps up in the front of the car are going to be overly high with all the actual hot parts near the firewall and fresh air entering at the front. Maybe if its really hot out and you are in traffic you might see idle temps climb
 

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I agree with this! Also with or without an aftermarket intercooler the air temps are cooled before entering the throttle body.. obviously an aftermarket intercooler out performs the stock one.. but the point is the same.. you’re not going to cause any damage what so ever purely because you do or do not leave the air filter box off.. ultimately do whatever makes you happy! I had mine off for 80k miles what no problem ever.
 

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The RS cover seal against the hood liner like a horseshoe. The front opening of horseshoe it is still open and grab air going in between the hood liner and the radiator support. The opening on top of the RS cover act as cavity collector to ram air inside. If the car is not moving it will draw hot air from the engine bay, as soon it start moving the air entering the front grill will push the hot air back escaping under the car. I'm not too worried about the horsepower the engine make while I'm waiting on a red light.
 

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Did you guys leave the stock box in or take that out as well? I just put my green filter in this afternoon, havent had a chance to drive yet.

Question 2...On my F150, I installed full air intake system (piping and filter). Is there any benefit to changing out the stock parts, vs running stock piping with the green filter?
 

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Did you guys leave the stock box in or take that out as well? I just put my green filter in this afternoon, havent had a chance to drive yet.

Question 2...On my F150, I installed full air intake system (piping and filter). Is there any benefit to changing out the stock parts, vs running stock piping with the green filter?
not really...the stock setup isnt so much of a bottle neck. People that are really pushing the limits might see some improvement. Id say save your money for an intercooler and tune if you havent already
 

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Thanks Rambleon. Kinda what I thought. I'm just getting started with the car (I've had it for a long time, but got the bug). AP is up next and then RMM and Intercooler. :)
 

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Get an RS airbox off of ebay. I got my brand new last year for like $80. It seals against the hood and keeps hot engine bay temps out and let’s you hear more turbo noises because it’s open on the end. Cheap and easy fun mod.
 

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Discussion Starter #20
Did you guys leave the stock box in or take that out as well? I just put my green filter in this afternoon, havent had a chance to drive yet.

Question 2...On my F150, I installed full air intake system (piping and filter). Is there any benefit to changing out the stock parts, vs running stock piping with the green filter?
I took it out completly I installed the green filter with cover off but the piping is compelty stock. I been driving 500km with it off already. I noticed you ear the turbo spolling and sound trottle response better the pedal feels lighter.
 
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