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Discussion Starter · #1 · (Edited)
So question for all those with FMIC, How are you managing to lower coolant temps in your setups? I have a mishimoto 3 core rad and fans. With current temps on the rise so do my coolant temps. seems fine around town usually somewhere around 185. Highway 70ish MPH 190-200 if i turn the a/c on 230+. My next plan is to put a gates racing water pump on and maybe a lower temp thermostat... any thoughts from those with fmic or ppl with experience bringing the temps down would be greatly appreciated. I know the air flow kinda sucks with the stock bumpers, but havent seen anything that would allow more air flow.
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Discussion Starter · #7 ·
230F+ is really in the danger zone. I'd first address the scoop block off as @healtoer suggested before driving the car.
only gets that high if i have to a/c on, as a mechanic myself i would never leave it up that high. it is concerning to me and this is my first subaru. never really had these problems on my other turbo cars with fmic
 

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Discussion Starter · #8 ·
this site is a trove of information, and i searched the site before posting this up just couldnt find anything in the search bar, i will try the block off plate as well. I do still intend to put a better water pump in the car, just curious if i should run a lower thermostat?
 

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Discussion Starter · #10 ·
You want to see hot, look at your intake temps when the A/C is on...

Any-time you put something in front of a radiator it diminishes the performance of the radiator. To make matters worse, you're using a radiator known (Google is your friend) to cause high temp issues; worse than OEM in some situations.

If you are using the Mishy fans, I'd ditch those first. They DO perform worse than the OEM fans. After that, make sure there is foam or shrouding to seal off the sides of the radiator.

Don't know what you're making for power, but the VA radiator works exceptionally well for street-to-light track use to ~500whp.

I wouldn't waste your money on swapping out the pump. The's a splitting hairs difference. There are a lot of other things that will have a more profound improvement on performance than swapping pumps.
thanks for the input and its not a problem to put the stock fans back on, i did put foam on the sides. I appreciate the advice on the pump, i really didnt want to pull the timing belt yet lol!! I will have look into a different radiator, any recommendations? Love killer b parts!!
 

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Discussion Starter · #12 ·
You are creating turbulence in the engine bay to no benefit, which yes, traps hot air.

With a TMIC that air cools the intercooler and the radiator is unaffected.
The TMIC draft lessens the suction of the draft pulled through the front end, but the rad is big enough to handle it by itself.

With a FMIC, that hoodscoop air is just counter to the airflow path through the front end, plus you're heating up the rad with the intercooler.
When you put a blockoff plate, by capping the top draft, you create the room for a stronger front draft, which obviously cools more effectively.
I don't know the best piece for the VA, but looks like the plates are under 100$.

You'll notice there are some hoods available that are actually the reverse of the OEM hood, with an opening that drafts air up and over the car.
These are effective in that they speed up the front draft to pull more air for cooling, plus downforce.

/Get a blockoff plate
Thanks already ordered the verus plate, and will drop my oem fans back in today
 

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Discussion Starter · #15 ·
I don't post much, but I would recommend you checkout the video that Flatirons Tuning did recently on the Subaru Cooling system (posted below). Looking at the picture of your engine bay, it looks like you using 2 high pressure (likely 2-way valve) radiator caps. Apparently Subaru don't like that configuration much. Based on what Flatirons said/experience is one of their guys runs a 1.1 bar cap on the expansion tank and 1.3 bar on the radiator and has had zero issues. Might be worth a try swapping your expansion tank to the stock cap to see if that helps or even vice versa. I haven't tried this yet, but I was going to.

Second Video on the Cooling System Function in Subarus (worth a watch if you have the time)
I will check that out, thanks for the links
 

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Discussion Starter · #17 ·
Good catch.

Yes, OP, also get rid of the caps and go back to stock....

If you need higher coolant pressures to prevent boiling/cavitation, you have other issues to address and caps will not fix it. If you bought them for the "bling" or because "aftermarket has to be more better," then you'll want to re-evaluate....
Honestly i usually do a lot of research before i buy parts, in this case i was in a rush to get to my tuner and my stock radiator was cracked… this is what i could get my hands on in the time frame i needed. The info on the caps was very interesting and i will be putting my stock caps on, i had never heard of a one way and two way cap before watching the video
 
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