Hi all, I posted my DFIC for sale and got a lot of questions why I'm moving on from it. So after answering a few PMs, I figured I'd just start a thread to explain my actions.....

First off, I've done a lot of IC testing. One thing I've learned, is that they aren't as much of a "simple swap" that many think. While the change mechanically is easy, the interaction with the car is anything but. Here's an example....

When I did a bunch of testing a while ago, with 91 octane one IC made better HP than another. Then I put in some 100 octane, and the results were reversed! How can this be?

What happens is that the S is tuned pretty close to the edge. Even stock cars with premium gas show some timing retard. So any change to pressure or temp in the intake can have some pretty interesting effects. So, the IC that did better with lower octane had a higher pressure drop than the IC that did better on race gas. The combination of cooling and pressure reduction took the car out of (mostly) timing retard, and the one that dropped less pressure and heat got hammered by the ECU. With the knock resistance of the higher octane, the ECU could use the full timing of the car, despite the fact that the more powerfull IC with race gas had worse thermal performance.....

What is a modder to make of all this? That it's more than just choosing the brand and price point. The different design philosophies interact differently with the rest of the system (yeah, nothing is easy). You have to make sure that what you're getting is aligned with what you do.

If you do mostly street driving, it might be good to look for thermal efficiency over pressure drop, as the RPMs are lower, and the pressure drop is non-linear (double the airflow and the pressure drop is more than double).

If you live at higher RPMs, a free-er flowing IC may be good, if you can keep IATs in check.

Now, while I do have a sawzall, I'm not at the point where I'm gonna cut up the front of my car (like Tuls) to get a huge front mount with the best of both worlds. I also have a water injection system to play with. And I now have a ported/polished head, and will be putting on a very free flow exhaust. So I'm working on using a lower pressure drop IC core, with other ways to help the temps.

Will this be better or worse? Don't know.... Stay tuned.....

So, is there a "best" IC? Nope. Nothing is best for all situations.

Also, I'm not as concerned with heat soak as some, and M7 has a large suite of options for the DFIC that deal with that. For sure I'm loosing access to this technology by doing what I'm doing. And I don't even know if this is the best way to go for me! But that's what I like to do, test and see.....

Matt

 

Matt is this on an '07, or did you accidentally post that here?

 

Ignorant question, maybe - what's an IC?

 

InterCooler


Dr. O. The preeminent tester You gotta love those numbers and get emperical data. Nobody can argue with emperical data.

 

Interesting observations, Matt.

I'm up here in Maryland to have John at Lucky Dog take a shot at progamming my ECU.

Because I have the ScanGaugeII, I was able to monitor IATs, and compare them with ambient.

I have the m7 DFIC system.

Cruising at 75 in 6th, IATs were approx. 10-12 degrees higher than ambient (which was about 40 degrees).

Going up a slight incline on I-95, IATs were about 14-16 degrees above ambient.

Running slightly downhill, IATs were about 8 degrees above ambient.

Of course, sustained pulls will see the numbers climb.

Anyway, there you have it!

I'd love to know what IATs are with other ICs under similar conditions.

But no way do I want do the testing...

 

I'm not a big fan of steady state IC tests... The post IC temps are relatively low, and the cooling air flow is relativly high....

But it's data!

Matt

 

Dr. O, So thin cores that allows cooling air through them easliy would considered good thermal eff? Like this one?


Quote...(If you do mostly street driving, it might be good to look for thermal efficiency over pressure drop, as the RPMs are lower, and the pressure drop is non-linear (double the airflow and the pressure drop is more than double).)

 

that go into the mix, that there is no easy answer. The only way to know for sure is to data log T-MAP values and timing retard.... It sucks, but that's the way it is.

With the Mini, the thinner core is hampered by a more conveluted cooling air path. Which will win? Depends on the details....

Matt

 

hornguys: my steady state DFIC temp measurements (with thermal probes pre- and post- IC and a SGII) are very similar to yours at similar ambient temps. Ambient has been rising here in Alb. into the 60s and I notice my thermal efficiency is improving, which is not surprising.
However, as Dr. O points out, there's not much boost at cruising speeds, even though the SC is working. Check your MAPs on the SGII and see when they rise above barometric (whatever that is at your altitude). --> Rarely I'd guess based on my observations.
btw, Matt, do you know of a way to interpret the timing data that the SGII dumps out? The numbers range from about 2 to about 50. Clearly 50 is very advanced, and 2 is very retarded , but where's "neither"?
cheers,

 

the Mini uses timing changes for all sorts of fast stuff. So it bounces around a lot. The best way I've seen to use timing is from a power run. If it's a smooth curve that increases with RPM, you're golden. If it's a jagged line that tries to increase with RPM, you're getting timing retard.

Now it's even more complicated. The Mini retards timing on a per cylinder basis. I don't even know what a single number would mean!

Matt

 

Isn't another factor in IC decision making also your geographic temperature area. As an example - isn't thermal efficiency more important in Florida/Arizona than it is in Canada?

 

The answer?

Tons of data has been posted & many, many hours of time have been spent on bolt on mods, the IC getting a good part of the discussion.

Matt, you just posted the most complicated & important part of the package. The Mini OS is like nothing I have ever seen, so many parameters, too many for my taste but it all works. Somehow!
Most, if not all, stand alone systems are pretty straight foward. They will see, basicly, the EGT & you yould set the timing accordingly, octane, boost, ect. As you point out timing for a single cylinder can throw off any collected data because the system, as a whole, is effected.
The IC? It's a benny that BMW added, a nice benny, that would help make more hp. That's it.... End. The after market ICs are like shoes, some work better for some and others work for some others, it's always the other one that works better, the one you don't have ( the green grass deal ). I have some white snake skin kicks I like a ton, however they're not for everyone.

All the numbers that can be collected need to be looked at as how the system reacts to them. The whole system. A single number, ign timing, might mean nothing. To get the result, "the answer", the equipment needed is far beyond the capability that most of us can afford, if we all pitched in & purchased, let alone have the ability to use all of it. There's now a 3 year course at UMAS for Autocad not that Autocad has anything to do with an IC but you can see where this post is going.
Ahh, the old days, it didn't take as long to blow your engine up. On the plus side you could adjust everything... Yourself.... with simple wrenches or the universal tool, vise grips ( you could use vice grips like a hammer, I'v seen it done ) & no IC.

I like my IC & it will not be replaced any time soon, if ever.

 

I haven't worked the numbers.....

Matt

 

But I've installed the alta air diverter and the m7 ram air scoop on my stock ic. I believe i have noticed more consistant power during my north carolina back roads sessions... especially when im on it for more then 20 mins... Not a suprising result to any of us im sure.

However, I finally have some cash free and will be installer temp monitoring equipment here very soon. I will make sure to get readings with these bolt ons and readings with the stock setup just to contribute the small bits that i can.

Honestly, I do have to say... even after long sessions where I am at wot as often as possible, the ic exit horn is not usually more then luke warm... Again not a suprise as the temps have been around 60 deg F or so latley but compared to the inlet horn the outlet horn is amazingly cool since ive added these pieces.

my humble .000000002

 

he drove and logged, I crunched numbers. The M7 Extreme scoop did almost as much as the GRS intercooler before he sealed up the diverter.

Now, if a scoop increases power, what's the limit on the drag it adds before it's a net loss?

Matt

 

Hello
Very good Topic Matt

If I go to GP IC for a JCW 2005 Kit (210Hp) the best way is remap my ECU?

Best Regards

 

It's not going to be a huge difference. But if you're going to retune, there are tons of ways to skin the cat. I can't say I've found a "best" yet. All (well most) have some appeal, and some issues. See if you can get the GP sofware loaded. That and the IC are the only differences I think.... But I'm not a GP expert, so I may be wrong.

Matt

 

Hello
Thanks Matt for the answer

Best Regards

 

Hey just so everybody knows: Canada does not necessarily have LOW Temperatures at all times and places! haha I live in the Vancouver, BC area which has a similar climate to Seattle-mild and WET. I know of many US areas that are cooler. That said I agree with you that high thermal efficiency of an IC/intake system would help out in higher temperature climates!

 

Along the lines of post #1 I recently read an article where due to the tuning of some cars power was actually lost in adding an aftermarket cold air intake. Something to due with the ECU set up to deal with a certain amount of airflow. But it was also said that some cars benefited from the change. Even if MINI likes the intakes,..how much is too much? Are some of these CAI actually taking a bit of power away? Maybe not over the entire RPM band, but here and there.

 

There are two problems with the DFIC's as far as I see,
one ;cooling air does'nt like to go through thick cores, too much resistance
and two; if and when it gets to the other side of the core its too hot to do any good .
Whereas the thin top mount only has a 90* turn ducted before it, the air gets to it and the resistance is much less and away it goes under the car. Most of these ideas were read from Corky Bell's (makes IC's) book and others.

 

So I've said this before (well, what hasn't been said before?) Why not make a top mount intercooler with the channels at 45deg. to horizontal? The cross sections would look like \\\\\\ instead of |||||| and the air would flow into, and outof the cooler much better. Can this be all that difficult for someonw who fabricates radiators?

 

Because they don't make them like that . Just bend the air in the scoop and hood area before it gets to the IC. Read all about IC's here http://www.bellintercoolers.com/pages/AAMain.html

 

I don't necessarily agree w/ yr DFIC review -

1) I recently attended a Dyno in which we hooked up a fan w/ flexible tube duct taped to the IC units and the air flow from the DFIC was impressive.

2) "When the air gets to the other side its too hot" - your implying that the air absorbs all the heat that it can prior to exiting the DFIC. While I have not seen data to this effect nor do I have data, I can tell you that after a good run when I place my hand on top the DFIC, the front and back are the same temp to the touch. For me the hotter the air coming out the back the better.

I have had stock, GTT and DFIC IC units and of the 3 for my car and living in a hot climate, the DFIC seems to make the car more consistent but thats just me.

 

are a bad fundimental design, but work on the Mini because of improved coolingn air flow. AS the cooling air crosses through the IC core, it heats on it's journey so that it's warmer at the back of the IC than the front. That's just the physics of heat transfer. And that's why Corky and others say don't do this. But then again, his book doesn't have a section on intercooling in cooling air starved conditions either!

Matt