GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER

Ram air Vs. Cold Air Intake

Discussion in 'Performance & Fuel' started by walmart player, Feb 22, 2013.

  1. walmart player

    walmart player New Member

    Joined:
    Feb 13, 2013
    Messages:
    18
    Likes Received:
    0
    what are the differences between the two?I know ram air is more expensive but is the extra cost really worth it? And on a ram air hood to you need to buy a ducting kit or does the hood already have the ducts built in? I ask this cause i have seen hoods that say they have the ducts already in them and also seen ducting kits for ram air.
    #1
  2. Conlan Rose

    Conlan Rose Super Moderator

    Joined:
    Dec 12, 2011
    Messages:
    2,113
    Likes Received:
    3
    Cold air intakes are better then ram air because ram air always end up sucking in hot air from the radiator. Cold air takes air from out side the engine compartment that is much colder and denser then in side the compartment.
    #2
  3. Enkeiavalanche

    Enkeiavalanche Moderator

    Joined:
    Apr 5, 2010
    Messages:
    5,365
    Likes Received:
    14
    There are a few hoods out there.. Steel and fiberglass.. I've had both Disney 034 (Custom).jpg Disney 036 (Custom).jpg

    Steel Ram air and Cowl From Goodmark

    And Ram air from .Cervini's. IMG_1543resize.jpg newav3.jpg Now in this pic is a hood from Goodhood(Keystone) and the Cervini. Differance? The Goodhood has duct that goes to the Air box, The Cervini is just open for air to flow in. How much air are you getting in those hoods? Not much... Between the two The strut brace on the Cervini is much stronger the Goodhood one on my friends is all cracked, Cervini's is a better built hood..

    - - - Updated - - -

    The Steel hoods that you see on top Both are open in the back (Cowl) The Ramair is not open.. There are a few other Co's that make hoods for our trucks Like RK Sport and Reflection..
    #3
  4. walmart player

    walmart player New Member

    Joined:
    Feb 13, 2013
    Messages:
    18
    Likes Received:
    0
    From a proformance point of view, which one is superior is another question I have.
    #4
  5. RayVoy

    RayVoy Active Member

    Joined:
    Apr 18, 2012
    Messages:
    2,122
    Likes Received:
    5
    IMO, using your butt-dyno, you won't see any difference between ram, CAI and factory. It (Ram, or CAI) may sound nicer, and that can make it worth the money.
    #5
  6. Enkeiavalanche

    Enkeiavalanche Moderator

    Joined:
    Apr 5, 2010
    Messages:
    5,365
    Likes Received:
    14
    You gotta remember.. Your driving a 5000lbs Brick which moves the air in front of it out of the way.. If anything With the open rears or both front and rear you may cool the motor more.. Some have put air intakes by the Tow hooks or under the front bumper.. You will get cooler air down there BUT how much you get up by the air box I'm not sure DSCF9861.jpg My friend Adams truck has it below the bumper Hard to see in this pic...
    #6
  7. SurrealOne

    SurrealOne Former Member

    Joined:
    Aug 14, 2011
    Messages:
    10,778
    Likes Received:
    13
    This is spot on. Street machines spend little time at WOT. WOT is where ram air, cowl induction, and CAI's tend to matter...

    Basically, if you don't intend to use ram air or cowl induction to duct cooler, faster, higher pressure air to the intake AND properly craft/tune the intake (specifically for your truck's engine at a given speed and air pressure) such that, together, they produce a resonant supercharging effect ... then your ram air or cowl induction is just for looks.

    If you DO duct and tune properly, you'll get the effect of having a light supercharger ... at a given speed and air pressure (for which you tuned) ... without the supercharger (because it's based purely on physics and pressure differentials) ... and you'll see a mild boost in ponies at that given speed ... at the expense of fuel, of course (because you'll burn more), presuming you've also tweaked the exhaust system to allow your engine to properly exhale.

    This really makes no sense for street machines because the place you tend to want to do this is at wide open throttle at top speed without the effect ... such that when you get there you receive a little kick. It makes a lot of sense for racing machines. Few are the people who can properly tune this, themselves, as there's a good bit of measurement, math, and physics involved. It's definitely NOT a bolt-on type of thing to do it, properly.

    As for CAI's ... it's the same sort of thing. Yes, they deliver cooler, denser air to the engine compared with warmer air from the engine compartment. No, it's not human-noticeable and, no, it's not going to get you piles of ponies or mpg's. Yes, it's measurable on a dyno, especially at WOT, where 3F degrees cooler can make a minor but measurable difference. The biggest difference CAI's tend to make ... is in how your engine sounds, not how it performs.
    Last edited: Feb 22, 2013
    #7
  8. sierra11

    sierra11 New Member

    Joined:
    Jun 26, 2011
    Messages:
    161
    Likes Received:
    1
    [MENTION=34858]Enkeiavalanche[/MENTION] where did your friend Adam get that bumper it looks awesome!
    #8
  9. TRPLXL2

    TRPLXL2 New Member

    Joined:
    Jan 13, 2009
    Messages:
    3,370
    Likes Received:
    8
    100_2682.jpg 100_2692.jpg 100_2683.jpg 100_2691.jpg 100_2690.jpg

    I put a unknown cowl induction hood, I bought it used on craigslist for $100. It was cheap because the whole passenger side corner was broke off, had to refiberglass the whole thing and build it back up. It is functional, as you can see from the underside shot. I chose to buy a GREEN intake kit, which seals pretty good on this hood but not perfect. The only definitive information I can give you as far as performance goes is this, I have a CST monitoring device in my truck. I watched the MAF reading for several weeks after the install, It multiplied the % by at least triple fold. I do believe it sucks a lot more air than it used to, I have not had it retuned since I did this. If you don't retune you won't get anything anyways, I have hptuners but am too lazy.
    #9
  10. Enkeiavalanche

    Enkeiavalanche Moderator

    Joined:
    Apr 5, 2010
    Messages:
    5,365
    Likes Received:
    14
    That would be a GoodHood Now owned by a Co called CoreMT
    #10
  11. TRPLXL2

    TRPLXL2 New Member

    Joined:
    Jan 13, 2009
    Messages:
    3,370
    Likes Received:
    8
    Well that would make sense that it's a goodhood, I reread your post and it makes sense about the cracking. Mine is cracking around the corners of the scoop, not to mention the large amount of water that stays in the hood at all times. When I open the hood, water just pours out of the drain holes underneath. Poor design but I love it, since then I have also put the Volant power scoop on it as well. Got it for $20 at Summit Racing in the scratch and dent thing.
    #11
  12. Enkeiavalanche

    Enkeiavalanche Moderator

    Joined:
    Apr 5, 2010
    Messages:
    5,365
    Likes Received:
    14
    Cool beans.. When I got mine It was painted up at Valanca up in the Bronx. Lou there is the same guy who built 3 trucks for the Goodhood ad's and he even sad the Cervini hood was better built.. SBN 2 067.jpg SBN 2 068.jpg Here's some more pics of my old trucks Goodmark Steel hood (Also painted up at Valanca's and here is Lou's Down in Daytona for SBN's SBN 2 072 (Custom).jpg SBN 2 071 (Custom).jpg SBN 2 070.jpg SBN 2 052.jpg
    #12
  13. TimTom64b

    TimTom64b New Member

    Joined:
    Jan 6, 2012
    Messages:
    518
    Likes Received:
    2
    I have an RKS cowl induction hood on mine... I've noticed some improvement when up to speed (above 40)especially when towing my camper... just seems to have more power. Of course this is only my observation and not dyno proven. :)))
    #13
  14. SurrealOne

    SurrealOne Former Member

    Joined:
    Aug 14, 2011
    Messages:
    10,778
    Likes Received:
    13
    The butt-dyno isn't terribly accurate... and is prone to observer error.
    #14
  15. TimTom64b

    TimTom64b New Member

    Joined:
    Jan 6, 2012
    Messages:
    518
    Likes Received:
    2
    What one really needs is the cold air intake... in combination with the ram air hood. The colder the air the more power you can build.
    #15
  16. SurrealOne

    SurrealOne Former Member

    Joined:
    Aug 14, 2011
    Messages:
    10,778
    Likes Received:
    13
    How do you figure? A CAI is ideally drawing in air from OUTSIDE the engine compartment. (Even the OEM airbox draws through the fender and not the engine compartment.) So an unducted ram air hood would cool the engine compartment, some, but should have no impact on the air temp of what a CAI draws in.
    #16
  17. TimTom64b

    TimTom64b New Member

    Joined:
    Jan 6, 2012
    Messages:
    518
    Likes Received:
    2
    My RKS ram air hood dumps directly into the top of my air box... way better then just cold air from whatever enters via the fender.
    #17
  18. SurrealOne

    SurrealOne Former Member

    Joined:
    Aug 14, 2011
    Messages:
    10,778
    Likes Received:
    13
    Is the airbox sealed against it or open to the rest of the (hot) engine compartment?
    #18
  19. TimTom64b

    TimTom64b New Member

    Joined:
    Jan 6, 2012
    Messages:
    518
    Likes Received:
    2


    Mine right now has about 1/2" gap between the air box and hood ram air opening. My plans are to install a seal around it... just haven't gotten to it yet. Planning on installing a seal similar to what is used where the firewall and hood meet. Even with the 1/2" gap the amount of cold air coming in would easily displace the hot air coming from under the hood.
    #19
  20. buckmeister2

    buckmeister2 New Member

    Joined:
    Nov 28, 2012
    Messages:
    247
    Likes Received:
    1
    You may be flowing 300% more air to the intake, but your engine, if it is basically stock, is not using it. The stock induction on our silverado's delivers more air than the stock engine can use, even at WOT. The stock filter element flows something like 1700CFM, while the 5.3 engine uses a max of around 750 CFM, if I recall correctly.

    As for "cold" air, the only significant diff will be when you are sitting at idle for a period of time and the air under the engine is somewhat stable (stagnant), i.e., not moving. At low speeds there is some movement of air through the compartment. At higher speeds, such as on a freeway, your under-hood air temp may be 10 degrees or so warmer than the outside air. Many tuners can be set to measure air temp at the intake. If you have one, try that out and see for yourself. There is just no significant benefit from a CAI on a NBS or NNBS Silverado, both of which have a shielded intake system. This is coming from a guy who used to swear that there were a few extra ponies under the hood after adding the CAI.
    #20

Share This Page