Has anyone drilled 1 1/2 inch holes in the plastic cover attached to the grill directly in front of the stock air intake? If you put in a K&N replacement filter for the stock air box in would seem that you would have true cold air intake with better air flow? It looks like you would get a ram air effect with the air flowing under the hood lip but over the plastic plate directly into these holes if you lifted the hood rod that slightly blocks this area flow would be straight into the holes. The only downside I can see is that some water would actually go in un-restricted if you drove in torrential rain.
Last edited by R Altima : 05-04-2009 at 08:45 PM.
Reason: picture added
After 1 week my gas mileage is up by1.75 mpg. But this is on a single tank so it is not proof that the holes have anything to do with it. I do live in Southern CA so most of my driving is at highway speeds.
No comments on any performance gain since my seat of the pants dyno is pretty subjective. This MPG gain is WITHOUT adding the K&N yet. I have to believe that if MPG is up then HP must be as well.
As far as drilling out the air box and removing the snorkel that would be counter to my whole premise that this could produce forced cold air into the box as opposed to relying on the engine to draw the air in.
Of course all the big after market intake producers would be totally bummed if my no cost hole drilling proves out.
After 1 week my gas mileage is up by1.75 mpg. But this is on a single tank so it is not proof that the holes have anything to do with it. I do live in Southern CA so most of my driving is at highway speeds.
No comments on any performance gain since my seat of the pants dyno is pretty subjective. This MPG gain is WITHOUT adding the K&N yet. I have to believe that if MPG is up then HP must be as well.
As far as drilling out the air box and removing the snorkel that would be counter to my whole premise that this could produce forced cold air into the box as opposed to relying on the engine to draw the air in.
Of course all the big after market intake producers would be totally bummed if my no cost hole drilling proves out.
You will never gain anywhere near as much from drilling holes as putting a SRI on the car. Also I would have a extremely hard time believing the holes are the cause of you increased mpg. One more thing HP increases normally result in MPG loses if any change not gains so saying that because your MPG is up your HP must be as well is pretty far stretch.
I typically find in these forums that people do not really read posted items but simply scan them for ones they find interesting or want to comment on. Therefore comments are typically not well thought out but are "off the cuff". No disrespect intended to anyone just a personal observation from comments I read not just on my post.
The whole idea behind my hypothesis is that drilling the holes would FORCE outside air into the stock air box there by increasing the air flow as opposed to any type of system that simply relied on the vacuum created by the engine to draw air in. Banks system for RV's uses this principle by installing a large intake positioned inside the grill with ducting to carry the air flow to the intake. In theory increased air flow would allow for better combustion increasing both MPG and HP. I am not an engineer and do not have access to a wind tunnel or DYNO so I cannot make any scientific judgments. I am a backyard mechanic with an interest in automobiles so I thought I would throw this idea out there.
My comment on MPG and HP stand since there are many aftermarket systems that claim to offer increase in HP as well as MPG so to say that HP usually results in MPG loss would not be true.
I welcome all coments and if anyone does know if this is plausible please let me know.
One more thing HP increases normally result in MPG loses if any change not gains so saying that because your MPG is up your HP must be as well is pretty far stretch.
I cannot state for the gains, as I havent done this myself, but i can say that both HP and mileage can potentially go up due to this. you cannot floor it, gain the HP and gain mileage while doing so. but when youre driving light footed and gain mileage, that is possible. and when you step on it, you can get more power...thats possible. and who knows, you may be getting a bit better gas mileage when you step on it with the intake rather than without. now, the reason an intake can drag your mileage down is if youre flooring it more often because you enjoy the power gains. but this is the whole thing with any intake....there's potential for both sides.
and i believe this is what the OP was stating.
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I typically find in these forums that people do not really read posted items but simply scan them for ones they find interesting or want to comment on. Therefore comments are typically not well thought out but are "off the cuff". No disrespect intended to anyone just a personal observation from comments I read not just on my post.
The whole idea behind my hypothesis is that drilling the holes would FORCE outside air into the stock air box there by increasing the air flow as opposed to any type of system that simply relied on the vacuum created by the engine to draw air in. Banks system for RV's uses this principle by installing a large intake positioned inside the grill with ducting to carry the air flow to the intake. In theory increased air flow would allow for better combustion increasing both MPG and HP. I am not an engineer and do not have access to a wind tunnel or DYNO so I cannot make any scientific judgments. I am a backyard mechanic with an interest in automobiles so I thought I would throw this idea out there.
My comment on MPG and HP stand since there are many aftermarket systems that claim to offer increase in HP as well as MPG so to say that HP usually results in MPG loss would not be true.
I welcome all coments and if anyone does know if this is plausible please let me know.
The problem is the stock duct is not air tight with the intake box so you can't build pressure up especially since you have a restriction in the airbox (filter). Your engine is not getting air pushed into it and I don't see it really making it any easier to suck like a SRI allows which is why I said I don't see there being any gains. I read all the post I just don't believe it is doing anything for you.
I have never seen any soild proof from aftermarket systems that they accutally increase mpg and HP but have seen shows that disprove gaining MPG. I also didn't say it never happens I was just saying you can't compare getting better MPG as having more HP they just don't relate.
I would believe that if you got the K&N air filter you might seen tiny gains but thats cause you are getting rid of the real restriction. Also the difference in air flow through a regular filter and a K&N is very minute.
I am not trying to say you are wrong in trying this in fact more power to you I am just giving my opinion that I don't see it really doing anything cause I don't think the stock air box is starving for air the stock duct already has air being blown in from the grill.
I typically find in these forums that people do not really read posted items but simply scan them for ones they find interesting or want to comment on. Therefore comments are typically not well thought out but are "off the cuff". No disrespect intended to anyone just a personal observation from comments I read not just on my post.
The whole idea behind my hypothesis is that drilling the holes would FORCE outside air into the stock air box there by increasing the air flow as opposed to any type of system that simply relied on the vacuum created by the engine to draw air in. Banks system for RV's uses this principle by installing a large intake positioned inside the grill with ducting to carry the air flow to the intake. In theory increased air flow would allow for better combustion increasing both MPG and HP. I am not an engineer and do not have access to a wind tunnel or DYNO so I cannot make any scientific judgments. I am a backyard mechanic with an interest in automobiles so I thought I would throw this idea out there.
My comment on MPG and HP stand since there are many aftermarket systems that claim to offer increase in HP as well as MPG so to say that HP usually results in MPG loss would not be true.
I welcome all coments and if anyone does know if this is plausible please let me know.
At anything less than full throttle, the intake and throttle butterfly are resistors in series. They restrict the air flow, so that the engine produces only the power needed to maintain speed. If you lower the restriction of the intake, or otherwise raise the pressure upstream of the throttle butterfly, all that will happen is that the butterfly will close a little, to keep the same total resistance. No increase in HP, no change in mileage. That is, unless you drive at wide open throttle most of the time. And the combustion is already about 98 or 99 percent complete, so "better combustion" is not going to happen, either.
At anything less than full throttle, the intake and throttle butterfly are resistors in series. They restrict the air flow, so that the engine produces only the power needed to maintain speed. If you lower the restriction of the intake, or otherwise raise the pressure upstream of the throttle butterfly, all that will happen is that the butterfly will close a little, to keep the same total resistance. No increase in HP, no change in mileage. That is, unless you drive at wide open throttle most of the time. And the combustion is already about 98 or 99 percent complete, so "better combustion" is not going to happen, either.
Well thought out comment and I am enjoying the feedback.
So following this comment one could come to the conclusion that all aftermarket intake systems are really only making your engine compartment look nice at anything less than wide open throttle.
On the other hand cooler denser air whether restricted or unrestricted will allow for better combustion so I will change my hypothesis from performance gain to "These holes with a less restrictive filter could, especially at highway speeds outperform the expensive but totally cool looking aftermarket intakes". While enjoying the feedback on this issue I also have to think "Why do most modern cars have snorkels that give access to some air flow from outside of the engine compartment as opposed to the older cars which draw air from a very short snorkel in the engine compartment".
Here is just another thought to generate more feedback on this post. Could it be that the automotive engineers may like cooler intake air as well? If I remember correctly from other posts I have seen here; the K&N CAI for the 2007-2009 2.5 incorporates the stock induction snorkel in their design.
Of course if these very cool looking aftermarket intakes were not so expensive I would probably own one myself.
The thing is taking off the stock snorkel and other pieces by the grill allow more air in your engine bay while driving. I have tested this and with the fujita SRI I had on average 2 degree cooler air then with the stock system at any speed over 20 MPH. At idle they were the same.
The thing is taking off the stock snorkel and other pieces by the grill allow more air in your engine bay while driving. I have tested this and with the fujita SRI I had on average 2 degree cooler air then with the stock system at any speed over 20 MPH. At idle they were the same.
This might be true, but you LOSE hp since you no longer have a RAM air effect.
This might be true, but you LOSE hp since you no longer have a RAM air effect.
You don't have a RAM air effect on any of the intakes available for this car or with drilling the holes. Unless you have some air tight system where the air is forced all the way into the engine its not RAM air.
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