• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Fiesta ST Forum and Fiesta ST community dedicated to Fiesta ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Fiesta ST Forum today!


FMIC really necessary?

Messages
475
Likes
227
Location
Dublin, OH
#1
I am planning to buy an AP from Stratified with a 93 tune (we have 93 here in Ohio) and an e30 tune. My plan is to run e30 all the time, but have the 93 to fall back on when e85 is not available. Or I may just get the e30 tune and uninstall the AP if no e85 is available on a trip. Every day there are posts here from people who say one of the first things to install is a larger FMIC. I respect everybody's opinion, but my guess is that many people here have developed their opinions by reading stuff here, which is not a bad thing at all. So here is my question. Is the larger FMIC really necessary in my case? I live in flat Central Ohio. No canyon roads, and cops everywhere. While I drive the car hard for short periods, I'm sure it's nothing like I would drive if I lived someplace with more interesting roads. I use a BT1 module from GoPoint Technology (which might be out of business) and the DashCmd app so I monitor intake temps and they are almost always within 4 or 5 degrees of ambient (sometimes less) unless I am standing still at which the temp climbs until I roll again. But with the driving I do I don't think heat soaking the stock intercooler is very likely. I would appreciate hearing what folks think is to be gained with a bigger IC.
 


TyphoonFiST

9000 Post Club
Premium Account
Messages
11,495
Likes
7,986
Location
Rich-fizzield
#3
I am planning to buy an AP from Stratified with a 93 tune (we have 93 here in Ohio) and an e30 tune. My plan is to run e30 all the time, but have the 93 to fall back on when e85 is not available. Or I may just get the e30 tune and uninstall the AP if no e85 is available on a trip. Every day there are posts here from people who say one of the first things to install is a larger FMIC. I respect everybody's opinion, but my guess is that many people here have developed their opinions by reading stuff here, which is not a bad thing at all. So here is my question. Is the larger FMIC really necessary in my case? I live in flat Central Ohio. No canyon roads, and cops everywhere. While I drive the car hard for short periods, I'm sure it's nothing like I would drive if I lived someplace with more interesting roads. I use a BT1 module from GoPoint Technology (which might be out of business) and the DashCmd app so I monitor intake temps and they are almost always within 4 or 5 degrees of ambient (sometimes less) unless I am standing still at which the temp climbs until I roll again. But with the driving I do I don't think heat soaking the stock intercooler is very likely. I would appreciate hearing what folks think is to be gained with a bigger IC.
This is what i did...I got a tune for 91oct....93oct....and e30....so as if I am on a road trip I just switch if needed when I fill up!

Sent from my SM-N950U1 using Tapatalk
 


codestp202

Active member
Messages
500
Likes
136
Location
CA
#4
As a former Ohian, I can say you def need the FMIC. If you are going to be doing pulls on a hot day you will heatsoak the intercooler so fast with a tune. I know how hot it can get and with such humidity. They are cheap enough that I think its a no brainer. Your car will be able to make more power and for longer since your charge temps will be much lower.
 


Last edited:
Messages
392
Likes
99
Location
Chesapeake
#5
If you are on a stock tune right now, then your ambient temps may not rise that much when moving. However, when you get the tune and you're running closer to 25-26psi (what my stratified tune was at) on pump gas, you will be generating a lot more heat and will be far more prone to heatsoak.

As pointed out, with FMIC being available from Whoosh or Depo for ~$330 shipped or finding one used for similar price or cheaper, it def makes sense to have one installed.
 


Messages
468
Likes
182
Location
corpus christi
#6
There's no other power mod after a tune that's more important an intercooler on our cars. You won't even gain much power if any (I hardly noticed a difference on the butt dyno), but it will be much more consistent and safe on the car. If your trying to save on cash, a full exhaust won't even be worth it until you're ready for a turbo upgrade. Its more of a cop attractor than anything. This is all just my opinion, others may differ.
 


TyphoonFiST

9000 Post Club
Premium Account
Messages
11,495
Likes
7,986
Location
Rich-fizzield
#8
There's no other power mod after a tune that's more important an intercooler on our cars. You won't even gain much power if any (I hardly noticed a difference on the butt dyno), but it will be much more consistent and safe on the car. If your trying to save on cash, a full exhaust won't even be worth it until you're ready for a turbo upgrade. Its more of a cop attractor than anything. This is all just my opinion, others may differ.
Even with the exhaust it's minimal...The next logical step would be the Dp....after an intercooler...that's one of the big bottlenecks of the system.

Sent from my SM-N950U1 using Tapatalk
 


Messages
468
Likes
182
Location
corpus christi
#9
Even with the exhaust it's minimal...The next logical step would be the Dp....after an intercooler...that's one of the big bottlenecks of the system.

Sent from my SM-N950U1 using Tapatalk
Yes I agree you 100%, that's what I meant by full exhaust. I should have said turbo back exhaust. There's probably 0 gain just adding a cat-back.
 


Messages
122
Likes
55
Location
Reynoldsburg
#10
I live in Reynoldsburg and commute to Dublin daily. I purchased my intercooler from Whoosh and it definitely made a difference in the summer. Leaving work in the heat of summer, I could feel the response of the car get "soggier" over time. Not so much after the install.
 


LaserWhisperer

Active member
Messages
562
Likes
201
Location
Portland
#12
As a former Ohian, I can say you def need the FMIC. If you are going to be doing pulls on a hot day you will heatsoak the intercooler so fast with a tune. I know how hot it can get and with such humidity. They are cheap enough that I think its a no brainer. Your car will be able to make more power and for longer since your charge temps will be much lower.
Agreed! As a former Michigander with a brief stint in Ohio, I can confidently agree with code. The humidity alone will suck the power right out of the car.
Short answer:

YES
 


Messages
425
Likes
84
Location
Brooklyn
#13
unlimited threads stating "intercooler is the best upgrade for fiesta st"
half unlimited threads asking if its true.

Just do it. I got an intercooler even when I couldnt install it and just left it in my trunk for 6 months and felt a difference.. thats how good an intercooler in your car is, jokes aside, it is the only absolutely best bang for buck upgrades for this car, everything else is optional.
 


BRGT350

1000 Post Club
Messages
1,075
Likes
762
Location
Grand Haven
#14
For me, I didn't have any issues with the stock intercooler for daily driving/autocrossing with the Mountune tune. Living along Lake Michigan, we rarely get temps above 90'F and some years we go an entire summer without ever reaching 90'F. This past June we had a week straight of temps in the 90's and that is when I noticed the stock intercooler struggling. Sitting in traffic really made the temps rise and they were slow to drop when moving. I went with the Mountune intercooler mid-summer and on warmer days, when temps were in the 80's, the intercooler made a difference in keeping the charge temps cooler and also cooled the temps much faster when moving. I put on my stock intercooler for the winter and the two weeks of driving my ST with temps ranging from the upper 30's to 50's, the stock and Mountune intercoolers behaved the same. Charge temps stayed close to ambient and didn't climb in traffic. It seems to me, based on driving around with both intercoolers, that as ambient temps get closer to 90 degrees, the importance of the intercooler becomes significant. When autocrossing with the stock intercooler, I never saw any peak charge temps that were a concern. I did spray my intercooler with ice cold water after each run if the air temp was above 80'F as a precaution. I plan to run the Mountune intercooler in the late spring through mid-fall and the stock intercooler in the winter. That will keep the Mountune intercooler from being bashed by rocks, sand, ice, snow, and salt.
 


Messages
114
Likes
17
Location
Scranton
#15
Realistically when you get your Stune a few pulls even in 30 degree weather, like it is here in PA, I see charge temps 25+ over ambient. Although it doesn't really bother me now because charge temps still remain under 70 degrees, in the summer when its 95 and charge temps were at 120ish, you can really tell the difference. I will be purchasing either a whoosh or depo before next season, but while it's cold out I'll continue to enjoy boost season.
 


M-Sport fan

9000 Post Club
Messages
14,000
Likes
6,697
Location
Princeton, N.J.
#16
^^^Yeah, I am even thinking about finally installing the Strat Flash tune IF this early cold wave continues, despite not having had the chance yet to install the CP-E IC in the cellar, and having just put back on the lesser traction (than my 200 tread wear Rs-RRs in the warm weather), factory Pilot Sport AS/3s. ;)
 


Messages
64
Likes
14
Location
Seattle
#17
I would like to offer a contrarian opinion, since every other answer has been to upgrade the IC.

A tune will unlock quite a bit of power from the "butt dyno" and make the car more responsive. An intercooler itself does not add horsepower to the car, but does prevent heatsoak. When the intercooler gets hot, the intake air temps get hotter, and we know that hot dry air is not as dense as cold dry air. Cold dry air contains more oxygen, and allows the car to make more power. A more efficient intercooler will give you colder temps for longer.

Unless you are upgrading your turbo or want to attend some track days, an upgraded IC isn't absolutely necessary. The stock IC isn't great, but it is sufficient for basic commuting and some back road shenanigans. On track the car would be much more susceptible to heatsoak. When you're pushing the car to it's limits, you will really notice the heatsoak in the IC. If all you're doing is some basic freeway driving, don't worry too much about upgrading that IC.
That being said, you can spend your money however you want. A better intercooler will definitely improve performance, but not to the extent that you'll be able to feel a significant difference.

In addition, the stock catback flows pretty well. Others have stated the downpipe is the bottleneck, but I would argue that the turbo is the bottleneck in the system. Have a look at the stock turbo inlet and see how much it reduces in diameter to feed into the turbo. A catless or upgraded downpipe might flow better, but again it probably won't be a significant difference. Upgrade the exhaust if you're looking for some more exhaust volume.
 


alexrex20

1000 Post Club
Messages
1,472
Likes
611
Location
Spring
#18
with hot charge temps the computer ain't adding as much timing, if at all. timing = power
 


Messages
85
Likes
21
Location
Toledo
#19
I'm just north of you in Toledo. My car is stock aside from a stratified e30 flash tune(and an optional 93 map in slot 1 I've yet to use)- I do not have an upgraded intercooler, and although it would be great to have, I don't think it's really needed day-to-day. My input/question for you:

Question:
How often do you do back to back or multiple gear(1-2-3-4 gears) pulls?

Why:
I find myself doing a LOT of 2nd-3rd gear pulls. I only really get into 4th if I'm really feeling froggy. Within that "pull" time, I see about a 25-30 degree rise in charge air temps,not terrible if you're just looking at temps. When I go to the track(1/4 mile) I see roughly a 50 degree rise in charge air temps. That's a LOT in 13-14 seconds. It still feels really good right now considering it hasn't been over 45 degrees outside in a few weeks. That being said, there is a BIG loss in power with a back to back or extended "pull." I've logged this on the dyno with back to back to back pulls within 5 minutes of total time. Link immediately following. You can see, 100% stock, the car doesn't really care what the intake temps are, it's going to just make about the same power. Once you start increasing the pressure ratios(moar boost), charge temps go up FAST beacuse you're getting out of the efficiency range of the factory turbo, and they will only increase with the amount of time during the "pull."

See this post: http://www.fiestastforum.com/forum/threads/1201-Official-Fiesta-ST-Dyno-Thread?p=258782#post258782

In regards to e30/intercooler:
Honestly, with e30, since I've installed the stratified tune, charge temps rise the same. Direct Injection cannot take advantage of the cooling effect on charge temps that ethanol provides as it does with port injection. Knowing that, the ethanol does do something that pump gas simply cannot: basically eliminate detonation/knock/preignition. With the 93 octane off the shelf Cobb tune, the car would have some knock count and would pull ignition timing every now and again. With the e30 tune, I have NEVER seen anything on the knock counter, but even better yet, I regularly see ignition timing being advanced up to 4 degrees. Both the Cobb 93 tune and the Stratified e30 tune run similar timing advance, not considering the advance in timing that running e30 allows.

In regards to running e30 in the winter:
If overall % of ethanol content of e85 drops, just add an extra gallon or whatever into the tank. I don't test ethanol content at the pump, and I get annoyed enough having to run my card twice/pump twice just to fill up. I just dump about 5 gallons of e85 into the car, fill the rest up with 93, and party on. The car doesn't care. I'm not gonna log the car every time I drive it, and I've never logged the car. I do "daily" the car, beat the snot out of it, and don't care.

Will I get an intercooler?:
Maybe. I'm cheap/lazy. The $650-ish I've spent on the Cobb and then the Stratified tune are enough at this point, not to mention whatever it cost for the CP-e rear mount. If I run across a Treadstone intercooler(TR6/8) for cheap and can scrounge up the couplers for it, I may do it myself, but spending over $300 on it for an intercooler at this point.... I just can't bring myself to do it. I get in the car, drive it, and go beat up on a lot of other "faster" cars with it. I put about a tank through the car a week and still get 280-300 miles a tank, mostly city driving, me beating the the crap out of it a lot of the time.

Here's my best 1/4 mile to date:
http://www.fiestastforum.com/forum/...read-Post-Here?p=256250&viewfull=1#post256250



tldr: get one if you want to do more than one "money pull" on the dyno, street, or track and care about consistent performance, run to run, everytime. Not paranoid/don't care, or don't drive the car hard often, no need to spend the extra $
 


alexrex20

1000 Post Club
Messages
1,472
Likes
611
Location
Spring
#20
Down here in Houston the temperatures are still hot. Today it was in the 80s. A upgraded intercooler is a no-brainer for people that live in climates down south. 40 degrees of rise in charge temp may not be a big deal when your ambient is 30 degrees. But when your ambient is 110, then 40 degrees added is huge.

My Depo intercooler was only $330 and I never see charge temps more than 10 degrees warmer than my intake temp.

Sent from my SM-G950U using Tapatalk
 


Similar threads



Top