Its not really my review, its Corky Bell's theory as wriiten in his book. I'm not sure touching a material like aluminum ,that diperses heat so fast would be a good indicator of temp D's inside the unit. However your experiments are probably more important and valid than the experts theorys.

 

I'm having a hard time imagining turning the IC 90* and increasing its thickness 4-5 times improves the starved conditions? After all, the air has to go in and out the same path regardless of the IC orientation.Unless I don't know something about the DFIC's. A straight flow after the scoop into the thick DFIC starves the car for cooling air less than a 90*ducted turn after the scoop into a thin TMIC? How much thicker are they compared to stock and the original Alta ,anyway? Maybe this is a good argument for a big scoop and a good diverter .

 

It's been my experience as an academic economist, that theory and practice diverge mainly to the many factors that are not controlled-for, or accounted-for, in the theory. There are very few theories that explain everything! I've experienced these divergences many times, in bicycling, audio, photography, and now automobiles. I have been logging lots of data from my DFIC and related intake system, and my observations tend to be consistent with what Matt (Dr Obnxs) often states. What surprises me most about all the posts here on NAM concerning IC modifications and related data is the consistency of observations. The variance in IATs, for example, is so high under anything we'd call normal driving conditions, far exceeds any measurable differences between one mod and another. I have measured treatment effects for various mods on my car of 2-3F. This is so small compared to the normal variation in IATs, or any temperature measurement at any point on the intake path, to make any conclusions about improvements pretty heroic.
I'm pretty sanguine about the effectiveness of the stock IC, especially when, as you point out, lots of air is rammed into it at 90deg. My stock IC, modified Alta diverter and Ram Intake worked pretty well but preceded my data logging capabilities. I think the DFIC works pretty well also, especially with some help in other areas to increase air flow and reduce heat transfer (see my write up on my website where this is all documented.)
I still think a lot of this is like polishing a turd, as my father used to say...

 

If you have the same amount of cooling air, then the thinner design will work better. And all is alligned with Corky's book. But the two geometries DON'T have the same amount of cooling air flowing through them.

Is it so hard to belived that turning the air 90 degrees down, and having the exit air hit all the crap below the IC, and fight against the air that went through the radiator, would choke a significant portion of the air flow?

There is NO rocket science here. More air can move through the flow through designs. Even though it's a non-optimal IC geometry. But all this gets mixed up in a lot of other stuff on IC effeciency as well....

Matt

 

Here we very much agree. Adding an improved scoop, diverter and ensuring a good hood seal is all that needs to be done from an IC perspective for many enthusiasts.

For me living in Florida, I noticed a performance improvement going to an aftermarket IC. Earlier, I commented on "where you live" as a factor in selecting an IC. The DFIC which is more thermal efficient than the freer flowing GTT seems to work better for me.

 

See, I told you, I nearly always find Dr O. to hit the nail on the head. There's no doubt that the scoop and diverter designed for the DFIC move a considerable amount of air through the cooler. (Now all we need is a cool/hot exit route as per my sketch elsewhere!)
Also there's much evidence that this horizontal airflow is superior to anything that can be achieved with the downdraft IC. Even a quick look at my see-through photos posted elsewhere will give a good idea of where the air is flowing, or not.

btw, Doc--I think you've mentioned a couple of times (and I stand to be corrected) about designing some kind of diverter under the car to help scavenge air from the engine bay down across the header. Was that you? and if so, are there designs out there for me to review?

cheers,

 

Heat in the engine bay already exits in the space around the header, and it does so very quickly; as long as the stock air dam remains intact.

 

I totally agree with you Bart!!

I used to live in Quebec, Canada. I've never had any problems related to heat or warm weather. I moved to South Florida last June, and my car's performance was really lovwer than ever before...

I got a Forge IC two months ago and I feel like its perfrmances are back. (All this with the previous 15% pulley)

I am not an expert, but from my experience, a good IC in Florida is a must to get the most out of a MCS.

Just my opinion...

 

So it's the FMIC exit restrictions mostly that prove DFIC's flow better? Does'nt the DFIC have to deal with some exit interferences and radiator hot air too? If you use the same scoop on both ,the available entrance air would be the same. Does'nt the smallest opening in a system describe its restriction? Sorry ,I guess like to be the devils advocate sometimes Or maybe I'm the stupid ,"can't get it guy" .

 

IMHO, this photo shows clearly how the air flows through the DFIC in a completely uninterupted path without much, if any, interference with the airflow from the radiators.



If you look "through" the airbox, and around the unibody structures in the picture, the air exiting the DFIC goes straight over the plugs and down over the header.
Actually if you look really close you can see the trailing edge foils on the rear of my DFIC!
k-huevo: maybe it was your posts I was referring to? Can you expand on the physical principles that make the air dam "pull" all that hot air out over the header? Can we improve it with modifications to the dam, or a different location for a dam?

 

Nice photo Dr. Phil . I'm starting to believe .But let me think about it

 

FMIC

 

But the DFIC design allows for a much bigger entrance hole in the scoop, as my RBH-FAD scoop proves. The aperture in my scoop is over 3x stock, almost 2x that of the Ram and nearly 1.5x of the DFIC scoop. Increasing the scoop aperture for a down-draft IC would, I believe, garner little additional air into the IC. As Randy Webb has argued there is pressure built up at the rear of the stock diverter where turbulent air is sitting not going down through the IC. I have not seen "proof" of this, mind you, but it is the basis of his RAF diverter for his airbox.

 

I’ve gathered my share of intercooler data at Watkins Glen & VIR this past summer and thus know the facts relating to most all readily available pieces. But for those who still believe in the DFIC have you considered the Docs (disturbing) question?

 

So how much "speed" do you think I'm giving up?



Longboard

 

Haha We are driving MINIs here.........not sleek slip streamed high velocity super cars! So you're losing NIL/NA SPEED! Keep enjoying 'BRICK/MINI' and your intercooler!

 

Only in the limit that the smalles opeing is almost all of the flow restriction in the system. In the case of the stock IC, you have the scoop, the turn, the radiator tubes and fins, then all the stuff under the IC. So the scoop, while it can be improved a bit, isn't almost all of the block, so benefits past the scoop can increase overall air flow. If you do electonics, think series resistance. If you don't do electronics, start!

Matt

 

My point exactly .

Longboard

 

Doc. P, Heres a different perspective of your uninterupted flow path in the Mini engine compartment I see just about everything in the way. Maybe you need streamline bottles,wires, spark plug cables,coils,cowlings , etc . Plus the air flow has to bend over 90*,through that stuff to get out ,if like most DFIC people you were to allow the air to exit from under the car. I noticed reading one of your threads, you considered make a scoop with an exit in the bonnet area after the scoop, you might consider that the top of the hood in front of the windshield is pressurized at speed .

 

Air flow revisited?

 

It is apparent from the front splitter that your car is a dedicated track car (as splitters are useless, not practical, and look ridiculous (to me) on street driven cars). With that large an opening for the intercooler and those thingies over the cowl the aerodynamics has been quite compromised from optimal.


Testing results???: Is the DFIC modified with a large scoop (and the associated aero drag) more efficient than, say, the GP intercooler?

 

The splitter indicates two possibilities: 1) that he is experiencing lifting at high speed or 2) he is a poseur. If the former than the discussion of drag is worthwhile but if it is the latter the entire discussion is null.

 

So what's the net loss (based on the tests) of the larger scoop and the DFIC? I'm trying to read between the lines of this thread, and I'm not quite sure what we're getting at.

Thanks to those who test and share; it helps those who don't test, don't know, and really want to make sound decisions for their cars.

mb

 

Here's the slickest production supercar out now! 1001 HP, 16 cyl, quad turbo! Check out the link for SPEED in a Bugatti Veyron.

http://www.dailymotion.com/video/x15...n-at-top-speed

Jeremy

 

Wow Don, you sure now how to market your business and get customers.

It amazes me that NAM will black ball people for speaking their mind about vendors but they allow vendors to pick apart NAM members.

And yes Don, my car is not a track car. But I guess you new that being all knowing and all. The scary part Don, is that after looking at your site you really do sell good stuff and for the "most" part know what your talking about.

That said, you are so abrasive I would never make a purchase from you.

Just the truth.

Longboard