FMIC and Coolant Temps
jdab555
Greenie Member
fax
Awafrican
Moderator
Yea I've never had that issue on the speed3 either especially if you squeeze the lower rad hose a little. Then over the next little bit I just open up the res after or before a drive and top off, no issues
jdab555
Greenie Member
I might be retarded, but on my current speed and my previous speed, every time I've done a coolant drain/refill, a stubborn bubble has gotten stuck and required multiple heat up/cool down cycles to work it out. Coolant vacuum thingy from HF, boom easy done no bubbles.
TL;DR: The splash shield under the car makes a huge difference and was absolutely worth it!
Update for everyone. So I bought the kit linked above and didn't realize it's mainly for filling the cooling system from empty using vacuum. That said, I was still able to use it to simply pull a slight vacuum and see if it held, which it did.
Next, I installed the splash shield / skid plate. To my absolute surprise, this doesn't attach to the bumper at all! I was stoked as it meant I could keep the bumper quick release. I did not install the fender liners for the wheel wells. I still have them, so we'll see.
So the results? Well that splash shield has helped tremendously! Holy shit, I can't believe it. I've been driving with it for about a week just to see the effects and on the freeway my temps drop below 200 quite often, even landing on the magical 187 sometimes. Temps will still creep to 219 if the vehicle isn't moving, but they drop so much quicker when approaching even surface street speeds.
Overall, I am blown away by the effects of this splash shield. I've never had one installed since I bought this car, so it would explain why I've always been shocked at how hot this car runs. I'm surprised I haven't read more about the splash shield when it comes to heat management, but I'm super glad it was suggested!
Update for everyone. So I bought the kit linked above and didn't realize it's mainly for filling the cooling system from empty using vacuum. That said, I was still able to use it to simply pull a slight vacuum and see if it held, which it did.
Next, I installed the splash shield / skid plate. To my absolute surprise, this doesn't attach to the bumper at all! I was stoked as it meant I could keep the bumper quick release. I did not install the fender liners for the wheel wells. I still have them, so we'll see.
So the results? Well that splash shield has helped tremendously! Holy shit, I can't believe it. I've been driving with it for about a week just to see the effects and on the freeway my temps drop below 200 quite often, even landing on the magical 187 sometimes. Temps will still creep to 219 if the vehicle isn't moving, but they drop so much quicker when approaching even surface street speeds.
Overall, I am blown away by the effects of this splash shield. I've never had one installed since I bought this car, so it would explain why I've always been shocked at how hot this car runs. I'm surprised I haven't read more about the splash shield when it comes to heat management, but I'm super glad it was suggested!
jazonk
Greenie N00B Member
Do you have pictures of your setup? I just installed the Cobb FMIC and am having my coolant temps 10-15 degrees higher as a result. I'm looking at making some ducting, so just looking for some ideas. I'm based in Texas, so I have to deal with the 100+ degree ambient temps.
Did you consider upgrading the stock coolant radiator as well?
jdab555
Greenie Member
This is the link (DIY: Radiator Ducting Gen1 (FMIC woes) | Mazdaspeeds.org, The New Era in Mazdaspeed, CX-7 & Ecoboost Forums!) for how you can make the side ducting, it's really only effective if you get your undertray in place and seal off everywhere else you can as well (like with this: JBR Raider's Air Damn for Gen1 Mazdaspeed 3 #MS3-AIR-DAMN - Revolution Performance Motorsports! (therpmstore.com)
jazonk
Greenie N00B Member
I've been looking at that thread as well, thanks. Some good pictures in there. I have a Gen2, so that part doesn't work for mine. Do the Gen2's need the top sealed off the same way? Looking at mine above the rad it's not even close to being as open as the Gen1.
jdab555
Greenie Member
On a Gen2 you probably don't since it lacks the under-hood ducting of the Gen1. I would try the undertray and side pieces, that by itself should make a noticeable difference. I have a TR8 with all the ducting in place and it's extremely solid, echoing all the points in the thread. I wouldn't bother with an aftermarket radiator unless you really want to. I have tracked my car with the current setup which is stock radiator, for 25 minute solid lapping sessions without exceeding 219F in 85F weather.
When you say "side pieces", are you referring to the wheel fender liners or the side shields?
Only because I bought these recently, here are the part #s:
- Driver Side Shield - BP4K-56-115F
- Passenger Side Shield - BP4K-56-114D
The side pieces you need to make where the intercooler piping passes in front of the radiator
