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FMIC, when are they needed?

15K views 96 replies 21 participants last post by  Heide264 
#1 ·
Just as the title reads. When are they needed? I've been reading they are only needed when you have a bigger turbo.
 
#36 ·
Now that you guys listed of a couple of them I recall hearing those names before in terms of ones that don't require cutting the crash beam, but I just couldn't think of them when I posted my last comment.

The cheapest TMIC option is to just find a used STI one instead of the stock WRX. The STI IC is a good bit larger than the OEM WRX version, so you will get a definite increase in efficiency and resulting drop in intake charge temps. If you just did that without any other mods I'd be surprised if you could measure more power even on a highly accurate dyno. Maybe you'd get a 0.1% increase average across 10 runs.

If you put a larger turbo on there though I'm sure it would outperform the stock IC, which is why the STI has a larger IC to go along with its larger turbo, higher boost, and resulting rise in air temps.
 
#37 ·
The cheapest TMIC option is to just find a used STI one instead of the stock WRX.
No can do man.. the WRX VF52 has a flanged output that isn't in the correct location to run the STI intercooler
, which is why the STI has a larger IC to go along with its larger turbo, higher boost, and resulting rise in air temps.
HAHAHAAHAHA... Scott man where are you getting your info??? The VF48 on the STI is (less the outlet casting on the compressor housing) THE SAME TURBO as the VF52 on the WRX.

They're exactly the same in terms of output and efficiency. STI factory tuned for more boost? Yes.. but same turbo.

But I guess it takes a real turbo guy to know that wouldn't it? :p
 
#41 ·
I'm an engineer and part of my job is designing fluid systems. Trust me when I say that all of the extra tubing and bends that a FMIC introduces have a large impact on flow restriction. In my line of work, just one or two 90 degree bends often mean the difference between a successful or failed design. Now factor in all of the extra volume that must now be pressurized.

Compare this to a TMIC which has almost no ducting whatsoever, and is paired with an airscoop splitter which is designed to maximize airflow across the intercooler, and you have a very robust and efficient design. You could argue that engine temps have more of an effect on TMICs, and that's true to a certain extent, but there are plenty of measures to combat that as well (increased intercooler surface area, intercooler spray systems, heat shielding, etc).

If someone has all of the dimensions of FMIC tubing, I can use my tools at work to tell you the restrictions. It's pretty easy stuff once you've got the diameters.
 
#40 ·
Think of it this way, a FMIC has about 6 feet of 3" tubing it needs to pressurize and the intercooler itself before the manifold sees positive pressure from the turbo.

A top mount has very little tubing, and takes very little time to pressurize andfeed positive pressure to the manifold. It also is cooled by cold air from the hood scoop but is more affected by heat soak from the under hood temps while not moving.

Just think about using a leaf blower to fill an inflatable pool with air (your TMIC) then take that same leaf blower and fill up a moon bounce that kids jump in (your FMIC)... which will be ready to be played with first?
 
#46 ·
I see what yall are saying to a certain extent, but I feel like the lag that y'all are referring to isn't as bad as its being made seem.

As far as heat soak there is no possible way the tmic can stay cooler than the fmic. That hood scoop can't collect as much or more air than a fmic
 
#50 ·
I see what yall are saying to a certain extent, but I feel like the lag that y'all are referring to isn't as bad as its being made seem.

As far as heat soak there is no possible way the tmic can stay cooler than the fmic. That hood scoop can't collect as much or more air than a fmic
Ever hear of, vents, water-sprayer, turbo blanket, header wrap, insulation or isolation heat-shielding... I can, have, easily, almost anytime I wanted get colder than ambient IAT into throttle any time I wanted with my TMIC... What are your IAT into throttle with your FMIC set up... :tongue:
 
#56 · (Edited)
FMS.. good analogy regarding the moonbounce and leaf blower.

Another thing I have a serious gripe with when it comes to fmic kits.. why the fk is the tubing so effin big? Or the core for that matter. Bigger isn't better its just bigger. Even at 40psi (which 99.9% will never reach on a race app let alone on the street) there is no need for 3" tubing. *face-palm* and people wonder why fmic kits introduce lag.. oi.. no forethought, no common sense. But people are dumb and continue to throw money at poorly designed fmic kits.

thermally.. a fmic IS more efficient when speaking of just the core location... however as mentioned by fms.. there are more factors to think about when choosing one vs the other.

edit: Donkey.. excellent link.. I'll be forwarding that to quite a few of my non-scoobie turbo friends.
 
#57 ·
Donkey said:
True,but I wasn't trying to be fair. If you want looks then sure,buy any old FMIC kit. If you want all out power with the best $$$ to hp ratio meth injection even on the stock TMIC is hard to beat. Now toss in a external water spray kit (free if you use your winsheild washer nozzles:)) and watch the numbers go up. A good FMIC is easilly around $800+.
I agree. Octane+cooling is a win. Factor in the lack of throttle response loss, and it's even better.
 
#60 ·
A good quality FMIC that is well matched to your turbo size isn't going to be that bad as far as lag and throttle response.. it's just not going to be as good as a TMIC. If you just want the look you could always install an interfooler, or install a FMIC and lose a little responsiveness. It isn't a huge deal.. I would say the biggest negative about it is the compromise in safety. Of course I have a FMIC, no airbags, etc. No one plans on having a front end collision, and I really don't plan on it, lol.

If you do decide to run one, remember, larger isn't always better, and don't cheap out with an eBay kit made from recycled Burmese Coke cans.. buy one that is quality made. Treadstone cores are some of the best, and ETS makes excellent products. If I decide to upgrade my FMIC I will be having ETS make it.
 
#61 ·
MainFrame said:
Treadstone cores are some of the best, and ETS makes excellent products. If I decide to upgrade my FMIC I will be having ETS make it.
I love the ETS FMIC kit. If/when I finally go rotated, it'll be run on an ETS FMIC...
 
#73 ·
The most popular right now is the ProcessWest TMIC. ETS is one of the best FMIC systems, though Perrin makes a decent small-core FMIC. Both are going to run you about $1000
 
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