CAI Heat Shield/Filter Box

[jrcook320]

Inspired by Steve (shauer) i decided to make a heat shield to help better control heat in my intake tract. Along with this I will be wrapping the turbo inlet pipe with heat insulating tape because it runs very close to the manifold. I may also wrap a heat shield or manifold blanket around the manifold, make a heat shield for the turbo, and wrap the cold air intake since it runs right over and behind the radiator. I'm not sure there is much benefit to that since airflow through the intake is so fast it doesn't have much time to pick up additional heat.

I started by making a cardboard cutout. I started with an oversize piece of cardboard (non corrugated works best) and marked where to trim and bend until I liked the fit. I cut a large hole for the pipe so it would not interfere with fitment elseware, then to adapt to pipe placement I made a separate piece to fit tight around the pipe and taped it to the main section. I cut 2 separate pieces to match the contours of the hood where the shield would contact the hood. I then trimmed the shield short so it didn't interfere with the hood, taped it in place, closed the hood and taped the contoured pieces to the shield working through the headlight hole.



I then made a copy of my cardboard mockup for fine tuning purposes:



Then traced that on a sheat of .060" aluminum and cut it out using tin snips and a jig saw to cut the hole. To bend the aluminum I clamped it to the work bench under a 2x4 and used another 2x4 as a break.



Test fit:







Throught the headlight hole:


Prime & Paint:


Before installing I sliced some 5/32" vacuum line down one side and pressed it over the edges that will contact the body, hood and intake pipe.

[blitzed310]

Very nice! I have always wanted to do this after seeing the work Jeff did using acrylic (you don't even notice the shield separating the block from the intake). I should start thinking about doing this as well.

[TheNeek]

Very Clean. Well played.

[shauer]

Very nice!

I like your design more than my current air box. Makes me want to do a second version of mine.

There is a big improvement in the intake air temp with this kind of shield. I can watch it with the intake air temp sensor on MS and the shield made a big difference, especially on hot summer days.

- Steve

[Layne]

Nice work! So are you going to upload your cardboard tracing so we can all print it out and make our own with minimal effort?

[82eye]

Nice work! So are you going to upload your cardboard tracing so we can all print it out and make our own with minimal effort?

LOl - was thinking the same thing.

I seriously fail. As I was looking at the pics, I thought about asking what the thing mounted on the fender wall by the fuse box was. It looks like a brake proportioning valve, then I realized - it's a brake proportioning valve

[HenryHide1886]

Very clean work. What did you mount the shield to? I don't see any visible bolt heads or such.

[E21Adam]

There are two bolts on the front and a bracket going to the old air filter bracket. That's all I can see from the pics

[jrcook320]

Very nice!

I like your design more than my current air box. Makes me want to do a second version of mine.

There is a big improvement in the intake air temp with this kind of shield. I can watch it with the intake air temp sensor on MS and the shield made a big difference, especially on hot summer days.

- Steve

Thanks. Reading your data was the deciding factor for me on whether or not it would be worth the effort.

Nice work! So are you going to upload your cardboard tracing so we can all print it out and make our own with minimal effort?

I can probably do that, I still have the carboard cutout, but it won't be much good for anyone unless your batter tray is removed.

There are two bolts on the front and a bracket going to the old air filter bracket. That's all I can see from the pics

That's all there is, but in hind sight it would have been a good idea to make another mount tab in front of the fuse box. I had some old bolts lying around from my e21 parts car that I chucked up in the drill and took to the wire brush on teh bench grinder, then squirted a coat of black engine enamel to keep em from rusting and baked em with the heat gun to make the paint hard. That makes the hardware hard to see.

[fullswing]

great work!

[Zan320]

Nice Work! That looks great

[undastan]

Well Done ! ! ! Thumbs up!

[DEZIAC]

Very well done!!! That's awesome, i've been thinking about making a heat shield all winter, great job lovin it!

[DrewDude320i]

I can probably do that, I still have the carboard cutout, but it won't be much good for anyone unless your batter tray is removed.

That can be arranged.

[bmac320i]

very nice job. Thanks fo the heat gun tip.

[vtgti]

Great write up! It's threads like these that prove to us all that we can do projects like these with simple tools that are inexpensive to buy.

[TKO383]

That adds a very nice touch. Awesome attention to detail as always. Now you need to put a big JEG'S sticker on it...

[JDB]

Nice clean well thought out a usual...
Damm that is nice under the hood!
What did you use on the oil filter housing/front cover/alt. ???

Jeff

[Alvaro320]

nice job man... to copy you, firs i need to move the battery to the trunk....

[jrcook320]

Great write up! It's threads like these that prove to us all that we can do projects like these with simple tools that are inexpensive to buy.

Thanks. You have quite a few of those threads yourself.

That adds a very nice touch. Awesome attention to detail as always. Now you need to put a big JEG'S sticker on it...

lol JEG's. and maybe a Lingenfelter sticker across the windshield..

Nice clean well thought out a usual...
Damm that is nice under the hood!
What did you use on the oil filter housing/front cover/alt. ???

Jeff

Thanks. The silver is just engine enamel "aluminum" with engine enamel clear coat. It gives it a nice color that is richer and more durable than "aluminum" alone which tends to streak and water spot.

[pthm]

curiosity, would making a heat shield show any noticeable improvement on a N/A car?

[TheNeek]

Josh,
Can't say it enough. The best CAI box I've seen for an E21. I'm not surprised that it came from you.To finish this off... do you have any thermocouples to do some temp readings? It'd be fun to read temps pre and post turbo, and post intercooler. Might give you some more info on tuning stuff as well. My friend did this on his water to air setup on his Mk1 4-Runner.

You think the template would fit on a 17x11? You could do an AutoCAD drawing and make it a PDF on 17x11, then folks could just print and trace if they could find a large format printer.

[blitzed310]

^That would be sweet! But I wouldnt be able to use it. Attila had a pretty badass "CAI" stubby running right off the FD. I know he isnt using that anymore since he went EFI

[shauer]

curiosity, would making a heat shield show any noticeable improvement on a N/A car?

I'm using a similar but less elegant version of this same CAI on my NA engine and it reduced the intake air temp by up to 20 or 30 degrees F depending on outside air temp and driving speed. At any speed over about 30 miles an hour the intake air was within a few degrees F of ambient.

This makes a difference you can feel on EFI where colder intake air equals more fuel. I'm not sure how big a difference it will make on kjet which does not compensate for intake air temp.

- Steve

[pthm]

I was just curious because I know that air is more dense when cold, and that the K-jet sytem measures air density. or so i would think