sandwitch some felt and Al foil, and just use Al duct tape to put it all together. The key is to create layers that trap some air. The felt will do this very, very well. The Al foil will make a very efficient barrier, and Al reflects radiant heat well.

Should be cheaper in the long run...

Matt

 

Hello Dr. Obnxs! Thanks for the results, but I will still be sticking with the HAI. The sound is what I care about, since I do only street driving.

Thanks again man!
-Cody

 

Funny I should read this now.
I just got in from putting the whole intake system back together. Eyeballing and guesstimating doing just that.
I didn't buy the blankets because they're just expensive.
I like the Dr's idea. If felt was good enough for nomads on the steppes it's got to work well.
Funny I've always known it was a good cold insulator but never thought about using it for heat Yea I know insulation is insulation

I really don't want to use tape on the nice shiny HDI box though


Off to plot and scheme....

 

Well went out and did some testin of my own tonight; below abiemt has already bee achieved (by 2.5 times my margin of error), but tonoight was a base for my ALTA, I'm going to take it out and insulte it later in the week and test it again, while its out I'm also going to test the stock box; I'll post my findings when I have results to all three.

 

I, unlike motor on, do not have the patience to wait until I have all of the numbers. So here are my initial, pre-insulation numbers from the Helix CAI, and the effects of the sheet metal between the filter and the engine.

To set up:
I used a Craftsman multimeter with a K-type thermoconductor. Updates roughly every .5 seconds. It was a partly cloudy night, 71F degrees outside and low-moderate humidity.



First Run: On the wall (sheet metal) of the Helix CAI.



Second Run: On the top of the filter near the rear of the car.


And... since the cable wasn't long enough... I had to get a little ghetto.



Procedure:

I took a series of simliar road conditions and driving styles over set periods of time. Obviously they weren't exactly the same... but I wasn't planning on writing an entire scientific paper on this. These are just some numbers to think about.

I used my digital camera attached to the dash to record video of the numbers on the MM as I called out speeds. So that is how I got these numbers. Means and Stdevs were calculated from the End Temp. Statistical calculations do NOT include the idle start temp, that is just for reference. All temps are in F. Recorded times in relation to actual time, for the most part, are sequential.

TEST




The difference between a few inches of space in the CAI makes almost a 33degree difference in mean. However, the numbers are more all over the place with the on wall readings... more then double the stdev of the filter readings. I think that alone is proof that there would be a benefit of insulating the wall of the CAI.

I'm looking forward to motor on's numbers as well as the numbers I will be getting when I insulate the walls.

 

Dr Obnxs's HAI findings are on-par in terms of conclusions with my own dyno pulls from well over a year ago. I also concur with the drivability difference, which in my opinion was an improvement, however the lack of power gain over stock lead me to pull the HAI off my car.

 

But if the sheetmetal is very thin, then it has little thermal mass. But it's definantly putting heat into the intake charge...

Anyone gonna make a CAI baffle out of one of those plastics? The mold would cost, but the difference looks to be measurable...

Matt

 

What plastics? I think I got lost someplace

 

that some industrius parts supplier might want to switch their CAI baffle from metal to an injection molded plastic. Much better insulator. No one has (other than Dinan) that I know of....

Matt

 

Ahhh!

NGH I'm afraid.

 

By running I mean DRIVING - from normal street driving to doing performance G-tech runs. I was surprised I thought the "box" would get hot but not to the degree that I thought it would.

 

From what I've read here can one conclude that for daily street driving that a CAI is perhaps slightly better than HAI?

 

Brings into the question - retaining stock box with perhaps a performance filter like ITG? At one point I was talking to MTH and my recollection was a comment that they had not seen any difference between aftermarket CAI compared to stock with a performance filter.

 

from an airflow perspective. Can't get enough in there without modifying it.

And the finding you refered to has been retracted....

So, here's how I see the standing.

Stock box works, but not great.
HAI has good throttle response, poor heat soak performance but doesn't make much power.

CAIs flow better than stock, but can be improved after purchase.

Matt

 

I think peoples responses are too focused around dynos, and I feel MTHs was as well. From a dyno perspective I can see that there wouldn't be much difference.

However, I don't think that is the main point of the CAI. I think it is more for the responsiveness of the engine. Then it just becomes a matter of physics. The less distance air needs to flow to get to the SC, the less restriction the SC will have, and the faster response your MINI will have.

From a dyno perspective, it doesn't really matter since if it takes a CAI (a) number of seconds to get to air to (x) CFM, and it takes the stock box a slower (b) seconds to get to (x) CFM... eventually they are going to reach the same velocity, thus, probably generate the same HP.

Just a thought... (read: I could be way wrong)

 

I agree with that statement because of the numbers I was pulling from the top of the filter. After driving a while and giving the filter a chance to cool down, the numbers did not jump up a whole bunch and stayed well below 100F.

I would imagine that with the HAI, the minute you come to a stop, you are getting almost 100% heat soak from the engine, as opposed to a CAI which is A) farther away from the engine B) separated by sheetmetal, which isn't the best insulator, but it still keeps some heat away.

 

I'm in stop and go traffic everyday and so far I haven't had any problems with the HAI. Even if you come to a stop, and get 100% heat soak....wouldn't that go away by the time you hit ~6k in first, or second gear? I personally can't see any difference whether I'm on the highway, or stop and go traffic.

-Cody

 

I wasn't implying that the HAI would be a problem for daily street use - just that based on the data the CAI performed slightly better for that specific use.

 

We're not saying that your going to have issues if you use an HAI (though as was mentioned excess heat constanly into the SC will wear it quicker) but that there is additional preformance to be had from the intake, one that we can measure on the street; the gain is likely to only be significant at the track and doing autcross ( I imagine this is we're the largest measureable gain will be recorded) Because the air entering the engine of a well insulated intake will already be cold and won't need to wait until the car is up to speed to get things cool again. And like you mentioned, you're choice is based on sound, not HP effinency, or MPG gains. After my insulation is complete the SC noise out side the car will be greatly reduced (just adding a metal top did quite a bit to knock down the exterior noise).

 

Most of it would, sure. But also remember that the first big gulp of air that your SC is getting is going to be really hot.

Compared to the CAI where my first gulp of air off the line is going to be cooler allowing for more compression from the get-go.

But I think you are right, most of it would be gone by the time you reach 25+mph.

 

are really splitting hairs...

Matt

 

Which equate to maybe a 1-2% perfomance difference... if that.

On the other hand.... What an awesome excuse to tinker!!

 

That's what it's all about.
Try some dry ice on the IC... It works... straped some on with a thermal blanket and...
Next on the agenda is to build an insulation tray under the IC & have it seal up on the hood with an evac louver on the bottom for air to escape ( not much, just enough ). With the air con, engine, radiators blocking the easiest air to get under the hood, it seems that isolating the IC might something to try.

 

At first I thought you were poking fun at me... then I though, "Holy Crap... he really did try the dry ice!"

Now that's what I call tinkering.

You also sparked my curiosity with the IC... hm....

 

But bouncing around leads to hap hazard under preforming mods, First the intake then the intake hose the the SC then IC then the head, injectors and cam then header (Turbo in the middle maybe) then exhaust, and and ECU remap to get it all working perfectly, optimizing each section as you go along; then the final product is one Kick butt reliable car.