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Discussion Starter #1
Okay...here's the story. A while ago I switched my factory airbox/panel filter over to a K&N cone. All I did was take the top of the airbox off, remove the panel filter and used a large clamp to attach the new cone directly to the MAF housing. While this seems to flow much better (and sounds awesome), it also sucks in hot underhood air (as you can see below), causing the car to bog down under heavy acceleration from a stop (especially in the 90 plus degree weather we've been having for a week a so now). Now, it's pretty well known that colder, denser air means more power. After all, that is the basic principle behind a CAI. However, I don't want to risk hydrolock, or spend the money on a CAI, so I decided to find my own solution.




Basically, I'm making a heat shield that will (hopefully) keep the hot underhood air away from the filter. The shield is similar to the ones that come in the K&N FIPKII kits.

Making the shield:

The first thing I did was remove the cone filter, the lower airbox piece and disconnect the battery. Getting the filter out of the way allowed much better access to the lower airbox, which needed to come out, as it would be in the way of the new shield.

Next, I grabbed a piece of tag board, a pen, and a scissors and just went to work fabbing up a template of each side of the new airbox. I then taped the side pieces together, and after a few more test fits and cuts with the scissors I had this:


Next I pulled out the tagboard template, and transfered it to a more sturdy piece of cardboard. After cutting out the new cardboard template and bending it at all of the edges (I'm puposely making the shield out of one piece of cardboard in hopes of being able to use one piece of metal later, that I only have to worry about bending it and don't have to bother with joining two or more pieces together), I test fit it once again.



Then, I put everything back to how it was when I started, because unfortunately I have to work today and will have to finish everything up tomorrow. I'll be getting a sheet of aluminum tomorrow morning and cutting/bending the shield into shape. I plan on having two layers of aluminum for the shield, with some sort of insulation between them (possibly expanding foam like Great Stuff), and then will have weather stripping on the top to finish off the edges.
Before I install it, I plan on using a digital temperature gauge to test the intake temps both before and after. I'll update this thread as I get more done.
 

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to me i think if you make somethin yourself you get more of a satisfyin feeling knowin you built not bought nice prototype looks like the focussport keep up the work
 

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Discussion Starter #3
Thanks a lot, that is kind of what I was going for. I just don't see the need to spend money on something I can make. And you are right, it feels better to make something yourself.
 

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but if you box it in, youre just making another factory style box and w/ that cardboard its probably going to be the same temp
 

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Discussion Starter #5
I'm making it out of two sheets of aluminum. The cardboard is just a template so I can trace it onto the sheet of metal to cut out. There will be two layers of aluminum with some form of insulation sandwiched between them.
 

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Very interesting...I like your style..thinking outside the box as they say.The two wall insulated design is probably a bit of overkill,but interesting.It would be nice to find a source of cool air to vent the box into.Good job.
 

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breakaway said:
Very interesting...I like your style..thinking outside the box as they say.The two wall insulated design is probably a bit of overkill,but interesting.It would be nice to find a source of cool air to vent the box into.Good job.
I don't think there is such a thing as "overkill" when it comes to getting the coldest air possible in your engine.
 

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my .02...
looks good. you should use the side of the battery and extend another aluminum piece to go right behind the headlight to channel as much of the air as possible. and maybe invest in an iceman upper tube as well.

Great work though. one of these days im gonna get motivated enough to do something like this.
 

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When I swap out my throttle body for the BDR, I'm going to have to aquire a new intake system (since I modified my current AEM to where it won't work on a larger throttle body [?|]). I was thinking about an Iceman intake, but I know I'd really miss the sound. I might look into an Injen short ram. I think it uses some kind of deflector.
 

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Discussion Starter #10
**UPDATE**Update: August 2, 2006**UPDATE**

This morning I headed off to Home Depot to pick up some supplies. They didn't have any aluminum sheets, so I went with some galvanized steel. I also picked up a can of Great Stuff expanding foam insulation for between the two pieces of metal.

I started by testing the air temperatures with the current setup (no heat shield, K&N cone on the stock MAF). I'm using an old Hayden digital temp guage that has two seperate sensors to monitor the temps. These pictures are of where I had the sensors mounted.

The first one is right down by the filter. This way I know exactly what temperature the air is that is being sucked in.


The second sensor is just in front of the heat shield of the exhaust manifold. I wanted this temperature so I can comparte the difference between the hottest part of the engine with where the air is going into the filter.


Here ar the temperatures that I measured. Temp 1 is the sensor by the filer, Temp 2 is the sensor by the exhaust manifold. The outside temperature was 91 degrees (measured using the same temperature gauge).

Temp 1 Temp 2
Idle 149 deg. 157 deg.
30mph 146 deg. 101 deg.
60mph 103 deg. 96 deg

At first, I thought it was odd that the sensor in front of the manifold was registering lower temperatures when the car was moving. But, after thinking of the fact that it was right behind the grill and close to the fan for the radiator, I realized that there was a good amount of air moving over the sensor, causing the temp there to be cooler than the temp of the air going into the filter.


With these first tests out of the way, I moved onto actually making the shield. I grabbed my template and traced it out on the sheet of galvanized. Next, I used a Dremel with a small cutoff wheel to cut the shield out.


After everything was cut out, and the edges were smoothed using the Dremel's grinder attachment, I made the two bends, and put it in for the first test fit.



That is as far as I am right now, I came inside to escape the 95 degree heat for a little while, and thought I would put a quick update on here. I'm heading out to make the second piece of the shield, or at least the template for it. Hopefully, everything will be finished up tomorrow morning. I'll keep updating this thread as I get closer to a finished product....
 

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good idea. i'm intrested in seeing the temps with the sheild. personally i think the shield is going to be restricting air flow. but hey ... who the hell am i!
 

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expanding foam REALLY expands, though, so you might want to maybe make a frame or form out of something, maybe wood or the like, so it can only expand to the thickness you want it to. maybe some thin foam insulation board? the pink or blue variety? that way, if it doesn't work well with the foam board, you can try something else. if the expanding foam doesn't work, you have to start from scratch, because that stuff is pretty hardcore in its stickiness- you know, gorilla glue is expanding foam that doesn't expand quite as much. it's practically permanent.

i like the idea, though. there are few things more awesome than making your own parts! keep it up!

lucas.
 

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Discussion Starter #14
After a little more work, I have the template for the second piece of metal done and traced out on the sheet of metal (after basically dripping sweat in the humid, sticky, heat). As far as the expanding foam goes, I've used it before to seal my sub's box and to seal some areas around the house and have a pretty good idea of how much to put in.

And as far as restricting air flow, that thought hit me as well as I saw how much room the shield was going to take up after the template for the second piece was on. However, I do still have the factory snorkel hooked up, and will be using that. Also, I'm going to do the HRW intake mod (cutting the little debris shield in the front of the snorkel's intake) and also running some form of a hose from the driver's side cowl to the end of the filter to direct in some cool, outside air. The HRW mod showed pretty good results in lowering air temps just by itself, so I think all of my work will just improve upon it. Well....I will know for sure tomorrow.
 

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aluminum gets hot for one, and like you said w/ the shield, theres less air moving to the filter, so youre having to compromise air volume for air temperature
 

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This is an interesting exercise, and I'm curious to hear the results - would you, for the sake of humoring me, shove one of those temperature probes down into the outlet of the factory snorkle to see what the temperature of air moving through it is at your various speeds?

This experiment has some bearing on a notion I've had about fabricating some type of bottom for my Cool-flo with a hole cut into it for the snorkle outlet.
 

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well yeah aluminum does get hot.. but he's using galvinized steel! secondly he's making it a sandwich style box with insulating foam inbetween the two layers of steel :)..
 

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Discussion Starter #18
This is an interesting exercise, and I'm curious to hear the results - would you, for the sake of humoring me, shove one of those temperature probes down into the outlet of the factory snorkle to see what the temperature of air moving through it is at your various speeds?
Yeah, I'll give this a try. I might have to redo all my temps from yesterday, as it just cooled off here significantly. It was mid 90's yesterday, and it's not anywhere near that now. Oh well, I'm heading out to finish it up right now.
 

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I don't think breathability is going to be an issue if you retained the factory snorkel to channel air, and having done the HRW mod recently, it does make some difference, esp at speed. If you're feeling really brave you could also look a t cutting (Carefully!) a hole in your hood and installing a small offset cowl like the older 300ZX. Shopping around in the local boneyard should enable you to find something you can use. Chops to you for doing it yourself, that's what it's all about.
 

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Discussion Starter #20
**UDPATE** August 3, 2006 **UPDATE
I don't really feel the need to cut into my hood.....I'll do the HRW mod and also run a tube from the cowl on the driver's side down to the filter, and I think that should be good. Anyway, onto the update.


It's almost done!! The second piece of metal is cut and after a few test fits, I have them bolted together. The second panel only has two sides instead of three. I did this for a few reasons....first, the third side would have been the back piece, where there isn't too much heat to block......second, it would have taken up extra room that the filter can use now.....and third, it was easier to build this way! I used some 1/4 inch by 1 1/4 bolts and some spacers and nuts to hold the two pieces together while maintaining an even gap between them. The foam is sprayed, and I am waiting for it to dry right now so I can put the finishing touches on. I just hope it dries before I have to leave to go to work...I want to see what the temperature guage tells me.

 
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