hello,
i have a stock MCS motor and want to start mods with a CAI,
Helix , Ultric, Alta are open types.
It looks like Webb, DMM etc close their box with a top.........
Any opinions on which is better for performance?
Does it matter?
thanks in advance
Boxcars

 

but not a lot. There are tons of threads on cooling the air charge and the like. Also check out the Volt (I think Longboard started a thread on it....) Metal lets through more heat than other materials....

But we're really looking at small differences overall....

Matt

 

FYI the Alta can have a top or no top. I have the top on mine

 

Most of the so-called open top CAI actually are closed when the hood is closed. At least my Alta does.

 

thanks
to all so far , and keep answers and opinions coming.
question to Jiminni???
any fit problems with your alta CAI and your M7 STB??
i have heard of notch stories on the CAI and don't want to do that.
thanks

 

It just touches the top, no biggie though. You can check my pic gallery, zoom in and take a look

 

I don't think a box top will matter that much as to be worth buying it. I mean I don't have any data to support this, and it may be out there, but its not crucial.

 

The Alta w/o the top actually comes with the rubber gasket to seal it against the hood when closed.

 

Alta, no top, with this.

 

So how did you stick it on?

 

Doh!...wrong link...try this. It's adhesive.

 

I have the Alta with a box top and the M7 bar. Top is purely for aesthetic reasons to me, and I just put a little sticky foam where the two make contact and have no problems at all.

Last 2 pics here [ http://www.blueminicooper.com/?page_id=10 ] show it without and with the top

without the top, the M7 bar does push down the rubber gasket, causing it not to seal as well against the hood, but I didn't notice any performance diff...

 

The battery box barrier? It fits?

 

Yep, just trim it a bit...takes 2 minutes.

 

Interesting Do you think it helps any? And how does it look? Thanks for any info.

 

Well, I went from a K&N "CAI"..cough cough...to the Alta with the Thermotec. On my Scanguage II, I saw a bit of a drop in temps...but it depended on heat soak. If you're soaked, you're soaked, especially in 110+ degrees. As far as looks go, it's got some ghetto going after about a year or so of use, but I think it ads that homebrew character

 

I just installed a Dinan and like it very much. Not noisy until you get into the go pedal hard.
http://www.dinancars.com/store/High-...62-p-3680.html

 

ALTA CAI with K&N filter

no top on mine and it makes a difference I have a fan by the cowl vent

 

 

Not sure what you are doing? Any pics

+1

 

I went from an open Alta to a closed DDM Works. For me it was a much better looking unit, a cleaner fit & way less noise w/ cover.

The Alta is wider than the bottom stock air box by an inch or so on the engine side. The gap is filled w/ a piece of rubber trim. The extra width limits future options for improved Intercooling options.

 

The CAIs on the market do not work (well) in my humble opinion because:
They attempt to draw air from an already hot engine compartment.
They do get any direct flow cool air from the front of the car without getting pre heated. Even if the air is semi cool from the front area it is heated in the intake tube to the T/B?
The cowl vents have very little draw because the windshield creates a high Pressure area and there is nothing to catch the air. Oncari and MOSS had a good idea with there cowl vents but they designed them in the wrong direction. Useless. The air goes right over the top of them.

If you remove the back of a CAI and try to draw cooler air this has very little effect. The engine demand for air does not create enough cfm so the small amount of air is warmed before it ever gets to the T/B?
I mounted a sensor to monitor the IATs to find this out. I taped several pieces of string over various areas of the hood and windshield and watched the movements at different speeds. After seeing the results I mounted an electric fan in the cowl area behind the modified opened back Alta CAI . It is controlled through a manual switch, boost or RPM control. It will pull in about 600cfm of nice outside air at any speed. It will not pull in heat from the engine compartment in fact if anything it acts as a heat remover for those under hood temperatures. And it is connected to my thermal fan control. After the engine is shut down all my fans will operate if temperatures raise above 200*. And no it will not drain my battery. I have a voltage monitor that will shut of the fan controller off if voltage goes below 11.5 volts. I have had it on my mini for several years. I even posted this info once before but did not get a good response?

 

wow
i like it Nitro, but probably beyond my capabilities as an early modder.
so far it sounds like my M7 bar has no fit probs,
a top on a CAI keeps it more quiet, but if the quality is good, then the seal on a no top CAI works on the bottom of the bonnet.
thanks so far for the info.
what about the ones taht open at certain RPM,s to kick in cold air only then??
keep info and opinions coming
boxcars

 

Cause maybe a lot of this is purely conjecture? The engine acts as a big air pump, just like a fan or vacuum cleaner. It will draw air from the cowl vent regardless of the pressure difference or air flow. There has been several other folks that have done data tests on the air around the CAI and the inlet at the front at anything above a fairly slow speed does supply plenty of ambient air. Being able to draw additional ambient air from the cowl vent just aids in the cooling process. As long as you are moving you are not really subjecting the CAI to any heat soak, especially if you use some kind of thermal break between the engine cavity and the CAI box.

 

I had the Ultrik. It was OK but didn't really pull in any more cold air than the stock unit. In fact, it probably pulled in a lot of hot engine bay air.
I switched it for a Dinan. I like the Dinan much better.
It pulls in air from the cowl vent by the windshield. This area is pressurized by the air flowing over your car while you drive, so you get some forced air effect also.
The air box is a plastic material similar to the stock box. It gives it some insulation from the engine bay heat.