tehe...how 'bout somtime in january

 

Try driving around for 1/2 hour, then put the probe on the airbox. 5 min is not nearly enough time to recreate how hot it is inside the engine bay at temp. If the radiator fans are running, that would be a bonus also.

 

HAHAHAHAHAHAH!!!!!!!!!!!!

 

DR-RJP:

Us 5th gen people have already completed your test that you are about to perform. save yourself the trouble. I am still trying to find the thread that was made about it for you. this is why i have been telling you this information because we have already thought about this, and ran extensive tests.

BUT... if you want to know for your own satisfaction, go ahead and have fun!

 

No, all of the scientists make this thread dumb.


And I hugely disagree that the air temps under the hood are constant whether you're moving or at a standstill. Even the electronics already in the car proves that this assumption is wrong. If the temps were constant, there would be no need for a fan attached to the radiator to try to cool off the coolant when idling on hot summer days. The temps go up and the fan turns on. When the proper temps are reached, the fan turns off.

2 years ago, I had a digital temp guage setup in the car with the sensor in the engine compartment that proved my point also.

 

Did you see the word "gain" in there??? You are pointing out the phrase "BAD FOR PERFORMANCE". Did I say that doing so will result in X hp loss? You assumed that doing the opposite WILL result in gains? That is your assumption but that's not what I'm pointing out. I'm merely trying to point out that hot air can potentially be bad for performance. Everyone is hacking their airbox letting in hot air into the intake for sound. But there is a side-effect.

YOU need to read it again and try to comprehend what is says, instead of jumping ahead into your conclusions about what it should mean.

 

I think you guys maybe misinterpreted his argument. He claimed that the engine bay temp isn't THAT much different from the outside temp when MOVING. However, when the car is not in motion (like how he mentioned about going down the track in Park), then YES.... the engine bay temp is quite a bit hotter than the outside temp. And I agree with this hypothesis. There have been studies done by Berk Technology which back up this claim; can't find the thread tho.

BWT, here is an idea.... why not hack the airbox and create TWO snorkel intakes instead of one (like fabricate something such as a tube that runs underneath the car which catches additional outside cold air). This way you get the benefits of the stock intake with the added cool airflow = more HP. BUT, it probably wont be as loud because you will be attaching a snorkel to the opening you drill into the airbox.

 

In addition to deezo's post,

If the air temps under the hood are constant, then why is there an air temp sensor attached to the airbox? Nissan engineers must have thought that outside temperatures differ and changes. If that's so, under-hood air temps are never constant either.

 

I really like this idea for those who want more sound but don't want to drill a box and are also not willing to spend the $$ on an intake

 

man, people can't read in here. here deezo... let me copy and paste what i wrote ok? here:

 

The studies of all of what we're doing and saying has been done by the members, ions ago. Berk isn't a credible source as far as I'm concerned especially when they jumped on the Frankencar idea after my man Steve got Frankencar up and running.

Hacking the box isn't what reduces the HP, removing the resonator is what does it. How hot do you guys think the air gets when flowing through the stock intake which doesn't attract as much heat as a metal intake pipe. There are more factors in the "hot air, cold air" thing than people care to talk about. They just keep repeating the same thing over and over again.

 

.................

You've said it here and I saw that but people continue to think differently about this. What I was saying was not directed toward you to make you feel like an idiot or anything of the sort.

 

http://forums.maxima.org/showthread....ght=hood+temps

 

Interesting. Consider this. How fast is your care moving while it's sitting at the staging line? How fast will air cool down once moving?? Will the air temp cool down even by the time you finish the 1/4 mile? Or will be just finishing ingesting all the hot air from sitting there? Considering that the 60ft time is critical, I would think getting colder air from the beginning would be best.

But with all that said above, Dave B has mentioned that in his experience, there wasn't much diff inbetween intakes in his 1/4 times. But a 1/4 time should not be subsituted for normal driving experience either.

 

Oh, and thank you... i didnt read your post untill after i made my other post to deezo. atleast you understand what I am trying to say.

 

oh ok.

 

This is the best way to resolve this debate, IMHO!

 

I just read the thread Kevlo posted. There's a couple of variables that remains unknown in Sascuderi's findings. Did or does he have the stock airbox with the snorkel when he did those tests? Or is he running a cone intake? Ok so he put the inside temp thermometer next to the intake however, that doesn't prove much about what goes on inside the airbox. The airbox acts as a heat shield. I do agree that things get really hot in there when the car is parked after running around for a while. The heat build-up takes a long time to discipate and that proved true because after he started driving his car again, the temp under the hood remained 10 degrees hotter until he parked the car again. Stopped at the light, under the hood temp is 28 degrees hotter!!! As you drive off from a stop, under the hood temp drops gradually. All that makes sense. However, those temperature differences is significant. IMO, the airbox helps shield the intake from hot engine temps. The snorkel does help too. Ever came home after being at work all day and your room is extremely warm? What do you do next? You open a window to let the heat escape and cool off your room! That's how I see the snorkel. Now you open another window, and the room cools off alot more. That is the principle in which I based my airbox mod on. As the car sits at a traffic light, temperature climbs, everyone understands that. Why help it alittle by keeping the snorkel and venting the box even more by not just hacking it but adding a duct of some sort to direct outside air in or let hot inside temp out. Since we aren't talking about air induction, air can either come in or out.

 

it would've been interesting if this topic was brought up at a forum for lambos and porches...

 

Come on now, that's not resolving anything. A dyno will resolve the issue and not a butt dyno like everyone else is trying to use. Maybe dki378's car feels slower after hacking the box because he expected it to be tremendously faster.

 

I don't see your point especially when there are some cars here that are faster than both.

 

I hacked my airbox by drilling 4 1/2 inch holes in the bottom part of it. It has made an improvement in the sound and i noticed an improvement in the throttle response, but not at WOT. I also used a midpipe from an ebay $40 ram air intake, sealed of and removed the stock resonator and drilled a 3" hole into the wheel well through the bottom of the box and dropped in a k&n filter and im satisfied with it all.

 

Silvermax:

You'll be pleased to know that I ran the tests anyway.

Here are the results. The photos may not show up yet as I am having trouble uploading them.

Here is a photo of the outside sensor placed in the wheel well:



The first readings are when the car was parked five hours after it had last been driven. The engine was not exactly "cold":



Both inside and outside readings are 85.8 and 85.6 respectively. BTW, these readings were taken while the car was in my garage.

I ran the car at idle for five minutes. Here are the readings:



Inside was 86.2 and outside was 81.3 respectively. The temperature dropped because I moved the car out of the garage. What I should have done is run the car for a longer period of time.

Next, I drove the car at 50MPH for 15 minutes. Here are the results immediately upon stopping:



Inside was 85.1 and outside was 76.1 respectfully.

It really does not matter for how long I run the car, or at what speed, the air outside will always be cooler than on the inside, and running the car at high speed does result in a cooler engine than having it sit at idle.

If I had let the car sit after running it for awhile, then the engine would definitely have gotten a lot hotter. I know, because when I lifted the hood to check the minimum temp, I also checked the max, and the inside temp was 94.2 degrees.

Given that amount of heat, running the car at high speed then would have resulted in a lot more relative cooling as well.

However, I doubt that the temperature inside would have dropped below 85 degrees at high speed no matter how long I would have driven it.

Now, I will also run a few tests with the sensor placed inside the air box, and also the snorkel later on, and compare that to various air box "hacks."

I'm doing these tests for my own edification, so I could care less if it has done it before.

However, I find it very interesting how uncomfortable it made some people feel that I was doing them at all.

 

I thought I was the only person that thought the same.

 

Have you thought of what you are going to do when it starts raining? As your left wheel roll on a wet road, it'll be kicking up water thru that opening and into your airfilter! Have you thought of a way to prevent water from entering your airbox???

 

That's a good approach, but I wonder if you need the 1/2 inch holes in addition to the 3" hole in the bottom. Or, did you seal up the small holes when you did it? Otherwise, you will be defeating the purpose of the wheel well input which allows access to cooler air than what transpires through the small holes inside the engine bay.

I have been doing some experiments on where best to place an intake on my car. Let me reiterate, this is for the benefit of my car, and my car alone, so don't be spouting things like "it's all been done before" and "you're wasting your time." I have already got that crap before on another post.

Intakes are not as simple as they seem. Not only do you have to consider the temperature of the incoming air, but also factors like turbulence and negative air pressure that occur due to the design and placement of the intake.

Bigger may seem to be better, but not necessarily. Here is an easy test to illustrate what I mean.

You'll need three ordinary drinking straws, and a piece of lightweight, but stiff piece of paper -- a birthday card or other greeting card will be perfect.

Stand the card on your table kitchen table. What you will do now is sit on a chair facing the card, and blow through the straw to move the card. If you can move the card, then slide your chair backwards until you reach a distance from the card where you cannot move the card anymore.

Now, take a second straw, and with the two straws, try to move the card. What you'll find is that you can now move the card with ease.

Carrying this analogy to the air intake system in a car, some people would think that a larger diameter tube (straw) would let in more air. But, as you saw with the straws, all you need to do is to add an additional intake (straw) of equal size to achieve the desired affect.

Speaking of the experiment, you can move the chair back until you cannot move the card with two straws, and then add a third straw. Voila! The card moves again.

The point of this is that you can take three small tubes and place them in openings in your bumper, and then bind the other ends and insert them into an existing intake opening, like the tube leading from the resonator to the snorkel, OR put them directly into the bottom of the air box. If you want to put them into the air box, put each one into a different side of the box, slightly offset from center so that the air streams do not collide, head- on.

For example, put one through the left side of the box, offset to the LEFT of dead-center; put one in the right side, of the box, offset to the LEFT of dead-center, and lastly, put the third one into the front of the box, with the tube BELOW dead-center. This configuration will create a little vortex action in the bottom of your air box.

I know that because I tested it out on an old air box using a small electric air pump as the air source. First, I sealed off the inlet and outlets of the box with duct tape, leaving a small hole in ther inlet, though. Next, I placed a piece of clear plastic over the top half of the box and injected a puff of smoke through the inlet while the pump was putting air inside. I watched as the smoke began to swirl.

I may do it again, and videotape the result, but i'll have to get another air box bottom as I threw out the previous one.

Isn't Science great?



That is the design I am employing

 

No one died and left me to be "god of the board” and I am not trying to be Mr. know-it-all like you claim. I have been here for a long time, and I have seen these results before. This thread is old news. There is nothing in this thread that has not been beaten to death before by other people. I was just giving the facts. If you don't like them, fine. If you don't want to like them, fine. If you chose to ignore them, fine. But don’t put me down by saying sarcastically that I am a know it all, or I am a god.

Fact of the matter is, is that you can run the tests, sure. Frankly, I could give two ***** less. I was trying to save you your time. When it all comes down to it, this thread is like saying "I found a book in my car, and I took it out, and now my car is faster"

The difference is nominal.

However, I would be interested to see your project dr. rjp, if you do decide to do it.

And on that note, I am done with you guys and this thread. This is last time I venture in the 4th gen forums to help out. Good luck with your project.

 

I did this last night. I just undid the bottom portion or the airbox and took it out. Then I loosened the MAF clamp to the resonator chamber and twisted it upside-down instead of loosening the four hex bolts that connects the MAF to the airbox. I strapped on the paper filter using zipties also and it sounds awesome at WOT after 5,500rpm. You'll definately know your doing WOT by the racket it makes.

 

thats exactly what i did. I like how if you do get into it and drive below 3500 you really can't notice that you modified it

 

Thanks, Silvermax, for all your help. No hard feelings. Give my best to the 5th Gens.

 

I still would like to see the tests that were conducted.

Some other references about hot vs. cold air I found on the internet:

Actually, the performance "gain" of cold air versus hot air is preventing the hot air from robbing you of existing HP, rather than adding new HP.

Perhaps, to correct this oversight, we should refer to "NET GAIN" of one set-up versus another.

Here's the deal, folks. No matter how many tests have been done on 4th Gen Maximas, there have never been any previous tests done on a 1998 Infiniti I30 automatic, with 119k miles on it, with all the usual factory options, plus a bunch of "everybody-gets-these" add-ons, sitting in the driveway of one Dr RJP in Jacksonville, Florida.

In the final analysis, those are the only tests that matter to me.

Can I get an "Amen?"

 

I totally agree rmurdoch.