best intercooler for stock tune?

[Karmic Man]

Originally Posted by digwm1

hey Karmin Man, haven't really experienced timing pull at the track yet but last week we had a heat + humidity blast to the 90's here in SoCal and car was definitely running softer than when at colder temps, i can only imagine it'd be worse at the track/guess we'll see as it doesn't look like i'll be getting my fmic before my next track day



hey 1&done, i saw the pictures and the thread regarding the forge fmic a while back, thing looks insane/awesome, my only issue with forge at the moment is i read somewhere that the ic pressure drops more than stock, which is something i would like to get away from, could you confirm?



word, dope

thanks ya'll

With a bigger IC than stock and especially couple with bigger piping there will always be more pressure drop (from the larger volume of the IC core) than stock even though the core might be more efficient and the IC is less restrictive.

That is why when you go for a bigger IC you should always get a tune otherwise the pressure drop will cause the power response and power delivery to be less than satisfactory.

[digwm1]

Originally Posted by Karmic Man

With a bigger IC than stock and especially couple with bigger piping there will always be more pressure drop (from the larger volume of the IC core) than stock even though the core might be more efficient and the IC is less restrictive.

That is why when you go for a bigger IC you should always get a tune otherwise the pressure drop will cause the power response and power delivery to be less than satisfactory.

word, thank you for your help again brother, are there not larger intercoolers that have less pressure drop? aka if i'm understanding their website right, dinan's fmic seems to have 0.7 less psi drop compared to stock?

[Eyeman]

http://www.extremeturbosystems.com/E...ooler-Kit.html

[BimmerAg]

Originally Posted by digwm1

word, thank you for your help again brother, are there not larger intercoolers that have less pressure drop? aka if i'm understanding their website right, dinan's fmic seems to have 0.7 less psi drop compared to stock?

I think there's been a bit of confusion on what pressure drop means here. What Karmic Man is talking about is the added volume of an aftermarket intercooler and piping. If we add volume to a closed pressurized system, the pressure is reduced, but engines are open systems so they behave a bit differently. With an open system, the larger volume just means it will take more time to reach the same pressure as before. This means that the car will feel a bit less responsive compared to stock, but it's likely very minimal and some people might not even notice. The Dinan website is talking about the flow pressure drop across the intercooler, which is a measure of how restrictive a flow component is. The Dinan fmic is less restrictive because it has less of a pressure drop.

[digwm1]

Originally Posted by BimmerAg

I think there's been a bit of confusion on what pressure drop means here. What Karmic Man is talking about is the added volume of an aftermarket intercooler and piping. If we add volume to a closed pressurized system, the pressure is reduced, but engines are open systems so they behave a bit differently. With an open system, the larger volume just means it will take more time to reach the same pressure as before. This means that the car will feel a bit less responsive compared to stock, but it's likely very minimal and some people might not even notice. The Dinan website is talking about the flow pressure drop across the intercooler, which is a measure of how restrictive a flow component is. The Dinan fmic is less restrictive because it has less of a pressure drop.

not sure i understand, so in the case of the dinan fmic, since the dinan has a small pressure drop, if it had same volume as stock, it would take less time to build boost yes? so, if i'm understanding this correctly, if two intercoolers have the same pressure drop, but one is larger in volume, the larger one will lag cause it takes longer to push the targeted amount of air through the intercooler and to the engine?

thanks for all the help guys

[BimmerAg]

Originally Posted by digwm1

not sure i understand, so in the case of the dinan fmic, since the dinan has a small pressure drop, if it had same volume as stock, it would take less time to build boost yes? so, if i'm understanding this correctly, if two intercoolers have the same pressure drop, but one is larger in volume, the larger one will lag cause it takes longer to push the targeted amount of air through the intercooler and to the engine?

thanks for all the help guys

Not exactly...if the Dinan were the same volume as stock, but with lower pressure drop, both systems would build boost in the same amount of time. Pressure drop is a measure of restriction in the system, so basically let's say at the compressor outlet you have 10 psi of boost pressure. If the stock cooler has 1 psi of pressure drop then the boost pressure in the intake manifold will only be 9 psi. Now if the Dinan cooler only has 0.5 psi pressure drop, the manifold pressure will be 9.5 psi. Because your engine is pulling air in from the intake manifold, you want the pressure there to be the highest, so the least restrictive intercooler is the best. The volume of the system is a separate effect, with larger volumes taking more time to fill up to the target pressure, so larger volumes will have more lag. Now typically, larger coolers have more internal passages so they are also less restrictive, so you're trading off lag vs peak performance. That being said, a well-designed cooler can have both better cooling capacity and lower restriction than stock while keeping the volume increase (and therefore added lag) minimal.

[CarJunkie]

I use the AD-E 650hp intercooler which is a much larger volume than stock, more than double. I did not notice any increase in lag when it was installed and was running the same map. Looking at my logs before are after, there is also no difference in what I can see as the "lag time" from boost rise to acquiring target:

From inflection point when entering spool (obvious intersect just before 0 pressure) to inflection point where target boost is acquired (slope of boost curve inverts) is about 1.4 seconds for both, when going WOT at about 2k RPM. From my butt dyno, I can tell you it happens faster above 3k and feels instantaneous at 4k.

Also look at the IAT's on these!

Stock FMIC:
http://www.datazap.me/u/bjymewa/log-...=0&data=0-3-15

AD-E FMIC (same tune):
http://www.datazap.me/u/bjymewa/log-...=0&data=0-3-15


Current tune takes about 1.5 seconds to reach target during a similar pull, but is targeting a higher boost.
http://www.datazap.me/u/bjymewa/log-...=1&data=0-2-15


Moral of the story: You won't notice the lag difference with any smaller unit. If you truly plan to stay on the stock tune, you have a world of options, and should be able to use something that requires no cutting and may even weigh less than stock. If you plan to track the car, any better FMIC will make a difference. I overwhelmed the stock unit running Cobb OTS stage 1 which is *barely* more aggressive than stock and pretty close to stock above 4k rpm where the car operates at the track. Intake temps were 80 degrees above ambient.

I have a slightly detuned map from Buraq for the track which peaks at 17psi and tapers to 13psi up top. We'll see if that is conservative enough for the AD-E unit. The "650" number applies to street use and quarter mile pulls. A 20 minute track session is another matter entirely, which is why I wouldn't even try to run my standart tune (383whp) at the track despite being well under the FMIC's reported HP capacity.

I hope that helps!

[BimmerAg]

Originally Posted by CarJunkie

I use the AD-E 650hp intercooler which is a much larger volume than stock, more than double. I did not notice any increase in lag when it was installed and was running the same map. Looking at my logs before are after, there is also no difference in what I can see as the "lag time" from boost rise to acquiring target:

From inflection point when entering spool (obvious intersect just before 0 pressure) to inflection point where target boost is acquired (slope of boost curve inverts) is about 1.4 seconds for both, when going WOT at about 2k RPM. From my butt dyno, I can tell you it happens faster above 3k and feels instantaneous at 4k.

Also look at the IAT's on these!

Stock FMIC:
http://www.datazap.me/u/bjymewa/log-...=0&data=0-3-15

AD-E FMIC (same tune):
http://www.datazap.me/u/bjymewa/log-...=0&data=0-3-15

Moral of the story: You won't notice the lag difference with any smaller unit. If you truly plan to stay on the stock tune, you have a world of options, and should be able to use something that requires no cutting and may even weigh less than stock. If you plan to track the car, any better FMIC will make a difference. I overwhelmed the stock unit running Cobb OTS stage 1 which is *barely* more aggressive than stock and pretty close to stock above 4k rpm where the car operates at the track. Intake temps were 80 degrees above ambient.

I hope that helps!

Look to me like time from zero to target boost is 1.3 sec for stock and 1.4 sec for the upgraded FMIC, so like you said nothing you'd really be able to feel the difference from. Those IATs do look awesome! Nearly 40 degree temp rise over the pull with the stock unit but the AD-E temps are FLAT! Awesome unit, how much trimming did you have to do to fit?

[CarJunkie]

Here is the thread, my install pics are there. The bumper did not require any cutting, but the structure behind it did. I didn't do the work myself (ADE installed it) so it's hard to give a lot of details on that.

http://www.1addicts.com/forums/showthread.php?t=1216355&highlight=Fmic&page=2

[digwm1]

thanks all, that was very informative, i think i understand it better now