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FMIC really necessary?

LILIKE16ST

Senior Member
Messages
862
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252
Location
Saltville
#41
Intercooler is a must imo if you're going to be tuning. As crappy as the stock fmic you can lose power just during a 1 gear pull especially in the summer. It doesn't really add power by itself but it will keep you from losing it which is kind of the same thing. If you're running along at 80 degrees and drop down a gear and run through 1-2 gears you will lose significant performance with the stock intercooler once you're tuned and with an upgraded one you wont. If you add in the fact that tune you're getting can now be more aggressive safely allowing for more power then it's a no brainer. Go with whoosh or depo both are mid 300 shipped and a really good upgrade over stock and can handle anything up to the 300 or so whp level which is any of the hybrid turbos or the mrx upgrade. It's a no brainer I went with depo as whoosh wasn't even available when I got mine over a year ago.
 


Messages
90
Likes
27
Location
Manassas
#42
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
The gain isint going to be that great (yes it will help some) the real BIG bottle neck is the turbo itself
 


BRGT350

1000 Post Club
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762
Location
Grand Haven
#43
From my experience, it depends on your climate. I never had any issues with a tune and the stock intercooler until the ambient temp was over 90'F. That had been a total of 5 or 6 times in the three years of owning the car. I have logged a number of autocrosses with a tune and stock intercooler without seeing charge temps over 100'F, and if I did, it was while waiting in line to go. I did upgrade to a Mountune FMIC last summer, but it never got warm enough outside to really see a difference. If I sat idle long enough I could tell that the air charge temp was reduced at a faster rate with the Mountune intercooler compared to the stock one. I use my stock intercooler for the winter without any issues. I only plan to run the Mountune intercooler in June-September, when the possibility exists to actually see warm temps.
 


A7xogg

Active member
Messages
580
Likes
143
Location
Hampton roads
#44
From my experience, it depends on your climate. I never had any issues with a tune and the stock intercooler until the ambient temp was over 90'F. That had been a total of 5 or 6 times in the three years of owning the car. I have logged a number of autocrosses with a tune and stock intercooler without seeing charge temps over 100'F, and if I did, it was while waiting in line to go. I did upgrade to a Mountune FMIC last summer, but it never got warm enough outside to really see a difference. If I sat idle long enough I could tell that the air charge temp was reduced at a faster rate with the Mountune intercooler compared to the stock one. I use my stock intercooler for the winter without any issues. I only plan to run the Mountune intercooler in June-September, when the possibility exists to actually see warm temps.
Some of us dont have tha tgreat Michigan air. When i did some logs before i got my intercooler, around 70 degrees with a thrid gear pull the charge air temp would be above 100 degrees. humidity kills
 


BRGT350

1000 Post Club
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762
Location
Grand Haven
#46
Yesterday I had a charge temp of 40'F, that is 1 degree above ambient with the stock intercooler. This morning it was 27. The highest I have ever seen was 120'F and that was stuck in slow moving traffic for a long time. Once I got moving, it started to come down. We do get some fairly high humidity days in Michigan, but they are rare.
 


BRGT350

1000 Post Club
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762
Location
Grand Haven
#48
I get about a 20'F rise in charge temp under max acceleration in 3rd gear. Colder ambient temps see less of a rise and warmer see more rise, but the average is around 20'F with the tune and stock intercooler. It is less than that with the Mountune intercooler and the time it takes to return to ambient is much faster than the stock intercooler. If I remember correctly, timing starts to get pulled when the charge temps are above 110'F. For me, that would take an ambient temp of 85-90'F, which is very rare. In 3rd gear, the car is already exceeding the posted speed limit and the intercooler can start the return to lower temps in 4th gear as the engine is no longer producing enough exhaust gasses to create significant boost.

I haven't been on a road course with my ST to see what the Accessport reports for charge temps. With the Fiesta Movement ST's, we had been running a ST pretty hard for filming a commercial in Brazil where the ambient temp was very warm and the car spend a great deal of time idling. There wasn't any noticeable loss of power. We ran another ST very hard at the Nashville Raceway in-field road course, along with repeated drag runs and slaloms on a very hot day in June without any issue. The same ST ran 35 consecutive autocross runs and the tires gave up before any loss of power was noticed. The same car again made a few trips to GingerMan raceway for filming without any issues. Those were stock ST's and I didn't have a method to monitor charge temps. We had more issues with overheating the tires. I wish we could have monitored the charge temps to really see how a stock ST does compared to a tuned one. I knew back in 2014 that the weak link to making consistent power was the factory intercooler, but we never had issues. Others running ST's in California and Florida also didn't report any problems, and many of those were used for filming at Sebring and Horse Thief Mile/Willow Springs.

My advice is to monitor charge temps, ambient, and intake temps on your car and your unique use case. Gather the data for how your car is used and how you are using it. Upgrading parts because a dyno says they are needed is only valid if you drive your car on a dyno. Collect data that is unique to your application. Working as an engineer for a very long time has proved to me that unique application cases and data collection are critical to making decisions. I was having beers with a Ford engineer a few years ago talking about use data and how people surveyed would tell you how they are using their cars, but the actual data from their cars proved something totally different. Collect your data and make your decision based on that data. You may need to get an intercooler right away or find the stock one is ok for now, but needed in the future if your plan to further modifications, or the stock intercooler is just what you need.
 


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