After searching and reading threads on heatshields, finding how ridiculously expensive they are to buy already made and being completely bored while on break from school I decided to make my own and IMO it came out quite well. I will do my best to explain step by step with the pictures I took and if any of the moderators find this helpful feel free to throw it in the e36 DIY library.

Materials (bought from homedepot):
1x2 ft sheet of black powder coated aluminum $12.47
weather stripping of your choice ( i got 2/3 in. window weatherstripping) $3.97
card board and tape FREE

Tools:
dremel (not required but helped to cut the hole for the intake)
tin snips
small file
hammer + 2x4 + vice (used to bend the sheet of aluminum)
utility knife

Time: about an hour

Step 1: Remove you intake

Step 2: Find a nice piece of card board that you can use to cut and make a template as a guide to cut your sheet metal.

Step 3: Once you have a rough template (I say rough because more then likely you will have to do some more trimming to your metal) make marks on the metal sheet where you will be cutting the intake hole as well as where any intial bends and cuts will need to be made.

*Steps 4 and 5 are interchangible I guess...I bent my sheet first*

Step 4: Bending the metal. To do this I placed a 2x4 in a vice and first bent the metal along the drawn lines I made. I then used a hammer to define the bend more. This step is fairly easy once you know exactly where you want the metal to bend.

Step 5: Cutting the metal. Now im sure you could cut the intake hole a number of different ways but with what I had available I used a dremel to slice the circle for the intake into 4 slices. I then was able to use my tin snips to remove the 4 pieces. I then used a grinding attachment for the dremel to smooth down and even out the inside of the circle. I followed this up with a file to get it as smooth and metal shard free as possible.

in this photo I have the hole cut and the metal bent
http://images.snapfish.com/3459%3A68%3B9%7Ffp337%3Enu%3D324%3A%3E%3A37%3E%3B9 4%3EWSNRCG%3D323345763394%3Cnu0mrj

here I have used the tin snips to remove a cutout for the shock tower and the area where the cruise control wires run and such.
http://images.snapfish.com/3459%3A68%3B9%7Ffp337%3Enu%3D324%3A%3E%3A37%3E%3B9 4%3EWSNRCG%3D3233457633958nu0mrj

I then brought the shield up for a test fit. I found that the part of the aluminum that would be nearest to the headlights and the radiator would need to be trimmed a little off the top so that it would not hit when the hood is closed. Here is a picture.
http://images.snapfish.com/3459%3A68%3B9%7Ffp338%3Enu%3D324%3A%3E%3A37%3E%3B9 4%3EWSNRCG%3D323345763395%3Bnu0mrj

Step 6: After test fitting everything it was time to weatherstrip. One of the write ups I read spoke of pep boys selling automotive weatherstripping. I just bought some window stripping from homedepot. It will do the job for right now. It seems to work nicely on the bottom and sides of the heatshield but to complete this project I will most likely buy some automotive type to put along the top of the shield so that it can seal fully with the hood.
Here are some pictures of the heatshield weatherstripped and installed for the first time.

http://images.snapfish.com/3459%3A68%3B9%7Ffp337%3Enu%3D324%3A%3E%3A37%3E%3B9 4%3EWSNRCG%3D3233457633967nu0mrj

All thats really left now is to re-install the intake and make sure everything looks good.
http://images.snapfish.com/3459%3A68%3B9%7Ffp337%3Enu%3D324%3A%3E%3A37%3E%3B9 4%3EWSNRCG%3D323345763396%3Cnu0mrj

http://images.snapfish.com/3459%3A68%3B9%7Ffp337%3Enu%3D324%3A%3E%3A37%3E%3B9 4%3EWSNRCG%3D323345763397%3Anu0mrj

From what I can tell you do not neccessarily need a bottom to this heatshield. Mine fit pretty flush after putting the weatherstripping on. The only thing I question is the durability of the weatherstripping. Time permitting I will try and get some better and more adhesive stuff that maybe even looks a little more attractive.

Please keep in mind I'm no professional, just a bored college kid (on a budget haha). I hope this is helpful to some people and if you have any questions or comments I will try and explain myself further. Good luck!

-Matt W

I know the ECIS is similar, but I would think that you still have a source for hot air, see arrow. Now look at the Comfortis intake...seals all around and top/bottom

I know the ECIS is similar, but I would think that you still have a source for hot air, see arrow. Now look at the Comfortis intake...seals all around and top/bottom
Haha... stuff a rag between the strut tower and the fender. ;)

or u can remove you horn and go CAI

I know the ECIS is similar, but I would think that you still have a source for hot air, see arrow. Now look at the Comfortis intake...seals all around and top/bottom

Ya I bought a 1x1 sheet of aluminum in addition to the 1x2 sheet. I am definately going to try and put a bottom on it so that it seals all the way around but I have yet to determine how to secure the additional piece of aluminum. My friend just got a welder so maybe I'll see if he can help me out.

sweet job man

When I had my 325 I made a similar heat shield (used a buddy's conforti as a template) and my sheet metal wasn't large enough, so I used rivets to secure the two pieces.

I know the ECIS is similar, but I would think that you still have a source for hot air, see arrow. Now look at the Comfortis intake...seals all around and top/bottom

true, but that does not justify the ridiculous price. nice work mcw323is.

true, but that does not justify the ridiculous price. nice work mcw323is. nor does a low price of a DIY justify lack of effectiveness...I'm not a Conforti fan or user...Cosmos V2 :alright

nor does a low price of a DIY justify lack of effectiveness...I'm not a Conforti fan or user...Cosmos V2 :alright
how is a DIY "lack effectiveness"? if you do it right, it does just as well as a conforti. Cosmos is good because there is no need for a heatshield, but if you dont feel like being ripped off and paying $120 for a CAI, you can easily make your own and if youre halfway smart at all you can make a decent heatshield that blocks a lot of heat.

I'm not a Conforti fan or user...Cosmos V2 :alright

same. i have a dinan:rolleyes . but it was free, so i dont care.:D

Good job on the project and the writeup. If people notice certain parts of it aren't as effective as they want them to be, they can alter it in any way they want.

It would be interesting to see how much heat transfer differs between a heat shield that blocks the flow from around the shock tower completely and one that doesn't. I bet you it doesn't really make a whole hell of a lot of difference, but I could be wrong....

Nice job. I did a very similar hack job with a piece of scrap aluminum flashing ( as a prototype until I get some nice sheet metal). My only suggestion is to move the front of the shield closer to the radiator. Your stock airbox intake comes in there . The way you have it now, the coldest air is now going between your heatshield and the radiator and into the engine bay.
Shift it over next to the radiator ( like the blue line in the attached pic)

Good job on the project and the writeup. If people notice certain parts of it aren't as effective as they want them to be, they can alter it in any way they want.

It would be interesting to see how much heat transfer differs between a heat shield that blocks the flow from around the shock tower completely and one that doesn't. I bet you it doesn't really make a whole hell of a lot of difference, but I could be wrong....

The heat of the material is insignifigant. The issue is making sure the filter draws fresh air. When you compare the amount of air going thru the tube even at IDLE, you realize that even having a very hot intake manifold/intake/whatever won't really heat the air up much at all. Trick is making sure you get fresh air, instead of heated engine compartment air.

Good job on the project and the writeup. If people notice certain parts of it aren't as effective as they want them to be, they can alter it in any way they want.

It would be interesting to see how much heat transfer differs between a heat shield that blocks the flow from around the shock tower completely and one that doesn't. I bet you it doesn't really make a whole hell of a lot of difference, but I could be wrong....



yeah I think that the forward motion/air flow would largely cancel out the effect of the intake empting the area and air moving from a higher pressure(behind the strut tower and fender) to a lower pressure (in front of the intake)

Good write up and a good starting point. I plan to do something a little different, but I guess I need to deal with water in the DME first:

http://www.pangaea-expeditions.com/images/productimages/mantec/snorkelextruded252.jpg

(OK, so I am kidding here...)

good job i really like that red intake where did you get it? it would look good on my car. i put a cosmo heat sheild on mine it took some effort to get it in there dunno why probablly couse it euro

good job i really like that red intake where did you get it? it would look good on my car. i put a cosmo heat sheild on mine it took some effort to get it in there dunno why probablly couse it euro

I actually got it off of ebay. It isnt one of those ones that you see listed over and over by sellers like procarparts and the like. If I recall correctly the seller claimed to be a tuning shop of some sort and had one or 2 of them left in stock and I think I paid like 55 for it or something.

Also after reading some peoples comments about making the shield come closer to the radiator I think I will try and address that tomorrow. Also I remember reading from the e36 DIY library the brake duct mod with a piece of vacuum hose tapping into the brake cooling duct. That might be a good way to get some cold air flowing up into the area around the intake.

My DIY CAI is almost the same as your/ except...
http://i24.photobucket.com/albums/c16/akanazasky/Heatshield.jpg

Nice write up! And good job. Props to you for using your head and creativity. I'll be taking some cues and ideas from you when I start working on my heat shield. Thanks for sharing.......

Nice job. I did a very similar hack job with a piece of scrap aluminum flashing ( as a prototype until I get some nice sheet metal). My only suggestion is to move the front of the shield closer to the radiator. Your stock airbox intake comes in there . The way you have it now, the coldest air is now going between your heatshield and the radiator and into the engine bay.
Shift it over next to the radiator ( like the blue line in the attached pic)

i agree, minor change, and it should improve airflow

where did u get the pipe & filter from?
i think im going to try to make one of these 2marrow

I got the pipe and filter off of ebay. It was from some sort of tuning shop that claimed to have 2 e36 specific intakes left and wanted to get rid of them. I would say any short ram air style pipe with a K&N would suffice.

Also I drove the car for about 30 min today sorta hard and the intake pipe is cool to the touch. Pre heatshield it would get quite warm. And whether or not this is all in my head...which it might be....on the highway the intake seemed to sound slightly different than before, sorta a deeper tone then before. Not that noticible but oh well.

I know for a fact that it works. i was racing one night it was probablly about 65 degres out. after i went home i checked the air filter and it was actually cool to the touch while the motor was very hot. so no its not in your head it really does work. just my $.02

Matt - i appreciate your writeup as it helped me build my own similar to what you made. my question is....how is your heat shield held in place? did you bolt it down to the sheetmetal anywhere or is it just hanging loose in there?

Nice job. I did a very similar hack job with a piece of scrap aluminum flashing ( as a prototype until I get some nice sheet metal). My only suggestion is to move the front of the shield closer to the radiator. Your stock airbox intake comes in there . The way you have it now, the coldest air is now going between your heatshield and the radiator and into the engine bay.
Shift it over next to the radiator ( like the blue line in the attached pic)
CORRECT!!! The ECIS unit I have allows air from the front of the car just like the factory air box. Why hasnt anyone used the inlet that feeds the alternator cooling duct for a CAI? I removed my alternator duct because it was allowing debris INTO the alternator. If its used to channel air to the confined area inside the heatshield it would be much more useful :D
~Phil

Matt - i appreciate your writeup as it helped me build my own similar to what you made. my question is....how is your heat shield held in place? did you bolt it down to the sheetmetal anywhere or is it just hanging loose in there?

back from the dead...and I'm just wondering the same thing?

Seems the pipe itself keeps it in place.

it looks like it is held in place by the shoulder of the maf housing.

it looks like it is held in place by the shoulder of the maf housing.
That's exactly what I was thinking.

i made my own cai . just a few tweeks u might wanna try . when i did mine i used a piece of cardboard as a template and this allowed me to get a nice fit around the fender . for the seal at the top i went to a wreckers and got some door rubbers and used that . great idea u had just add a bit to it and u will love it even more . here is a pic of mine http://forums.bimmerforums.com/forum/showthread.php?t=671224 p.s. i also used a bubble wrap foil covered insulation on the inside of the shield to keep the heat off the filter . with all that done after driving the car to full temp the pipe and the filter are cool to the touch

nice write up. does it make a huge difference? (heatshield being hot and intake cold?) or is the intake still warm?

What will happen if you dont have a heat shield? Will it damage the car, or just not get as fresh of air?

where did u get the pipe & filter from?
i think im going to try to make one of these 2marrow
Hey! how the F#$% did you manage to do that. Scary man. You mean my internet surfing is being watched by big brother? Creepy. But the IP address is wrong.
213188

how much difference will the temperature make for the CAI tubing? does a slightly warmer air cause any power impact? i always thought it was more for better flow than "colder" air.

i've read in "fuel efficiency" forums that sometimes warm air gives you better mileage and power.

Hey! how the F#$% did you manage to do that. Scary man. You mean my internet surfing is being watched by big brother? Creepy. But the IP address is wrong.
213188


What???:confused

I built one from scrap for my Grand Cherokee. I haven't yet got round to building one for my 318 yet, but in the meantime I thought you might like to see a step by step guide.

cardomain.com/ride/2667734/5

Notice I used door trim to form a seal, which is much better than double sided tape. Plastic is recommended as a lower transfer of heat than metals. I think it is possible to create the 90 degree angle using the toaster method, but this is not something I have tried yet.

I'll be posting my BMW on the site shortly.

Looks pretty good man.. If you ever make an xtra to sell let me know..

Subscribed. :D