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What option to pursue for max benefit?

  • Lid on.

    Votes: 3 60.0%
  • Seal on the hood

    Votes: 1 20.0%
  • Leave it alone as it makes no difference.

    Votes: 1 20.0%

  • Total voters
    5
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Discussion Starter #1
At present I do not have a lid on my air box and run a Cobb stage 1 air intake. It came from the dealer that way. I'm participating in the VelossaTech Big Mouth group buy but is this a waste of money without the lid on the box? So buy a stock lid or just mod the open box and seal it against the hood? Thoughts?
 

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well... I like a closed box myself ... all that hot engine air rushing into the filter/turbo .. or a "sealed" box drawing it from "fresh" (is the temperature of the air really different by the time it hits the turbo)?? no clue … :unsure: .. but I just "feel" better knowing its air more directly from outside … so personally, id fabricate a lid .. but as several of the aftermarket CAI are "topless" im gonna guess its not an issue … just personal taste ….. however having the bigmouth would still be a benefit id say no matter if the box is capped or not .. cuz in the end its "forced" outside air directed at the filter specifically
 

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I am running it a open-ended green filter and an RS airbox lid. And I have had no issues with charge air temps. They never really go more than 10 degrees above ambient since I installed the 3.5" fmic. in the winter months I've seen in go a few degrees below ambient. So in my case I don't know that the big mouth would really benefit me other than it looks awesome.
 

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For me personal: Try to keep as much of the hot air from the engine out. Closed lid or seal against the hood, whatever you like most
 

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Discussion Starter #5
All good points. The FMIC upgrade is in the cards for the near future, and will likely be installed concurrently with the Big Mouth. I do like the RS lid, but I'm not buying a complete air box just for the lid, because I'm also a cheap SOB... :D
 

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All good points. The FMIC upgrade is in the cards for the near future, and will likely be installed concurrently with the Big Mouth. I do like the RS lid, but I'm not buying a complete air box just for the lid, because I'm also a cheap SOB... :D

yeah I thought they were available before but I can't find them. Have to get to holebox it's like 70 bucks. Pricey for the lid.
 

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I'd suggest diverting the ram air funds into an upgraded intercooler. Intercooler should be your first performance mod imo. What good is a few degree cooler air going to matter when your stock intercooler heat soaks it and your car cant make power? It will look cool though
 

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Discussion Starter #8
As it stands it'll be a FMIC/Big Mouth combo going in concurrently once Depo has stock. I ordered a stock lid from the dealer and it'll be here tomorrow. The RS lid is pretty but not $100+ pretty.
 

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There is benefit to getting the coolest possible air at the highest possible density to the stock turbo inlet due to its small capacity. This reduces the required compression ratio of the turbo and keeps it in a more efficient operating condition, which gives more mass flow and less heat into the charge pipe.

Our baby turbo needs all the help it can get on both sides. Better intake + better FMIC. And at highway speeds the ram air should bump up the intake air density as well providing a bit more turbo efficiency. Admittedly, I'd like to see some speed vs intake pressure data...
 

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Our baby turbo needs all the help it can get on both sides. Better intake + better FMIC. And at highway speeds the ram air should bump up the intake air density as well providing a bit more turbo efficiency. Admittedly, I'd like to see some speed vs intake pressure data...
Id really like to see some logs from a 3rd or 4th gear pull with the widemouth vs with out it. Ideally same day/temps. Best to see with someone who has an aftermarket intercooler too. After this next round of their group buy's, i hope someone takes the time to do it!
 

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I can certainly understand the theory and it makes sense. All I know is that was my 3.5 inch intercooler my charger comes never get over 10 degrees above ambient. And I'm running an open-ended green filter with an RS lid. I am also running a stage 3 tune by JSt. With fully tightened wga preload. I'm pushin 24.5 PSI out of that baby Turbo. And I don't get high charge temps. I suppose it's possible that since I'm right at the max of the turbos capabilities if the intake temp was a little bit cooler I could pull a little bit more power at the same boost and timing. But I really think it would be negligible. Now if you were completely stock running the stock intercooler I could see how it could help a little.
 

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Discussion Starter #12
OK, got my lid today and Ford very thoughtfully didn't bother to put any screws with it. It fits fine with the Cobb filter FWIW. Anyone know what size the screws are supposed to be ? I'm not super worried as the hood keeps the lid on but it's a nice to know.

Maybe I'll try doing the data as rambleon84 suggests once I have parts...
 

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Little late to the party here, but I am running the Velossa Tech Big Mouth, and RS Airbox with a K&N Drop-In. I have and always will be a big fan of the K&N. There are also small drain holes bottom of the airbox that could be enlarged if someone wanted to.

I am thinking I have over-killed this now with excess breathing. I would be just fine with the Big Mouth, stock airbox and lid in place, and the K&N, all for what I use my '18 FOST for. Oh, and the symposer has been deleted. Pulling cooler air from the front by using the Big Mouth was my reason for that. Giving the air a place to go through the airbox, was my reason for using the RS Lid.

The RS lid looks cool, but a better investment would be the hood shocks. I just see more road dust on the filter from using it with the other items.
 

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Discussion Starter #14
Hood shocks? I'm assuming you mean replacing the prop rod with lifts? I've already put on the Dark Ice Designs hood lifts on and the fact I can move around in the engine bay without dodging the prop rod makes it totally worthwhile. Same with the Steeda jacking rails, not having to mess around with lift pucks if you're not using the factory jack on the pinch points and being able to lift the car anywhere along the rail makes maintenance much easier.
 

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Discussion Starter #15
OK, one more question (Hah!) My new airbox lid came sans screws. Anyone happen to know what size screws are supposed to secure the airbox lid to the bottom? I have to say it is a little quieter with it on, and I miss the whooossh a bit.
 
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