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Stock radiator is just awful.

DAW

Member
Messages
143
Likes
171
Location
Arizona
#1
So, this probably isn’t the first or last discussion about the factory radiator. The last few weeks it’s been a battle to keep the car from overheating in this Arizona summer, temps anywhere from 105-111+ daily for months. Anyway I did a bunch of research and of course the usual YouTube installation videos and commentary. I pulled the trigger on mountune, and oh boy I can not believe what the temps are now. The install took me about 3 hrs, including taking my intake out and hard pipe for east of maintenance, Draining and filling. I did it alone with the car on jacks. Anyway I’ll cut to the chase, before radiator I’d see temps easily 215-225+ daily driving, and at idle it just plain overheated upwards of 245. The mountune radiator I see temps 184-190 same driving, and 190-200 idle for longer periods. So regular driving that’s about a 30degree decrease in temps, and to me that’s a HUGE score! Here are some random pictures from the removal. 4F9CE348-E067-4B1F-AAEA-15EF4CE6175B.jpeg F1449196-A9B4-448D-B6BF-44B030BB15E0.jpeg 8E4A7803-9241-41E8-AA6A-CC4326D0396A.jpeg A98C2F57-A637-4C55-A804-A5D06C8603C8.jpeg F0EE9659-0A23-49BA-833D-D43252632B5B.jpeg
 


Messages
306
Likes
338
Location
Virginia
#3
How did you manage the balancing act with the a/c condenser and crash beam assembly? And getting it back on and realigned? I've done this before with someone that had done it on their own car, and I can't imagine trying to do that part without help.
 


Fiestig

Active member
Messages
748
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779
Location
Pacific Grove, CA, USA
#4
How did you manage the balancing act with the a/c condenser and crash beam assembly? And getting it back on and realigned? I've done this before with someone that had done it on their own car, and I can't imagine trying to do that part without help.
You don't have to take the front off to remove or install a radiator.
 


OP
DAW

DAW

Member
Messages
143
Likes
171
Location
Arizona
Thread Starter #5
How did you manage the balancing act with the a/c condenser and crash beam assembly? And getting it back on and realigned? I've done this before with someone that had done it on their own car, and I can't imagine trying to do that part without help.
You don’t need to take the front end off at all to do this, But I did slide it in from the bottom.
 


Messages
306
Likes
338
Location
Virginia
#6
You don't have to take the front off to remove or install a radiator.
That's news to me. I know the stock radiator will come out without taking the crash bar off. I did the Mishimoto radiator on my '15, which I know is huge. Maybe only really needed for that one.
 


Messages
73
Likes
80
Location
Arlington, TX, USA
#7
So, this probably isn’t the first or last discussion about the factory radiator. The last few weeks it’s been a battle to keep the car from overheating in this Arizona summer, temps anywhere from 105-111+ daily for months. Anyway I did a bunch of research and of course the usual YouTube installation videos and commentary. I pulled the trigger on mountune, and oh boy I can not believe what the temps are now. The install took me about 3 hrs, including taking my intake out and hard pipe for east of maintenance, Draining and filling. I did it alone with the car on jacks. Anyway I’ll cut to the chase, before radiator I’d see temps easily 215-225+ daily driving, and at idle it just plain overheated upwards of 245. The mountune radiator I see temps 184-190 same driving, and 190-200 idle for longer periods. So regular driving that’s about a 30degree decrease in temps, and to me that’s a HUGE score! Here are some random pictures from the removal. View attachment 32367 View attachment 32368 View attachment 32369 View attachment 32370 View attachment 32371
What fluid did you opt for? I'm in Texas, thankfully not QUITE as hot as Arizona, but still see those temps get up there when it's 102° and 75% humidity here.

Sent from my SM-G975U using Tapatalk
 


OP
DAW

DAW

Member
Messages
143
Likes
171
Location
Arizona
Thread Starter #9
What fluid did you opt for? I'm in Texas, thankfully not QUITE as hot as Arizona, but still see those temps get up there when it's 102° and 75% humidity here.

Sent from my SM-G975U using Tapatalk
This stuff, seems to work as advertised, bought two, used about 1 1/2 of them. 10D6E48B-4DBF-42D6-AEA9-D9D5B027D428.jpeg
 


Messages
388
Likes
663
Location
Ontario, CA, USA
#10
Best money I spent. I use to see 192 at idle no matter what, ac on at idle jumped to 193 but now with the CPE IC and Dizzy stage 2 I see 196 at idle with ac on and 193 without. And that’s in 95 degree weather
 


Fiestig

Active member
Messages
748
Likes
779
Location
Pacific Grove, CA, USA
#12
I drove like a madman in vegas at 110deg-115deg in 2018 and stuck on the 15 for a while at 112 at idle for at least an hour or so. Never got close to overheating with stock rad. Weird...? The only thing I do at coolant change is add 6oz if Royal Purple Ice.

Now... Let me clear something up.... The stock radiator is still junk in comparison to a mountune, or in general for that matter...lol
 


Messages
493
Likes
637
Location
Sioux Falls, SD, USA
#13
Damn you guys are selling me on this and I live in BFE ND where I dont even need a radiator most of the year.

I saw a fairly disturbing 220 degrees on the interstate, cruise set at 79mph for a couple hours, in 90° ambient on my road trip last week. Granted the Rad was PACKED with bugs but still I expect 190 if I am not beating the car.
 


OP
DAW

DAW

Member
Messages
143
Likes
171
Location
Arizona
Thread Starter #14
Damn you guys are selling me on this and I live in BFE ND where I dont even need a radiator most of the year.

I saw a fairly disturbing 220 degrees on the interstate, cruise set at 79mph for a couple hours, in 90° ambient on my road trip last week. Granted the Rad was PACKED with bugs but still I expect 190 if I am not beating the car.
Good thing you didn’t have to stop for anything, cus it would have been overheat city for you. It’s 110out today, city driving my temps where 183-185, just awesome!! Love this thing 😍
 


M-Sport fan

9000 Post Club
Messages
13,996
Likes
6,697
Location
Princeton, N.J.
#16
Damn you guys are selling me on this and I live in BFE ND where I dont even need a radiator most of the year.

I saw a fairly disturbing 220 degrees on the interstate, cruise set at 79mph for a couple hours, in 90° ambient on my road trip last week. Granted the Rad was PACKED with bugs but still I expect 190 if I am not beating the car.
That IS high, as my factory radiator never even sees near 200*F on the highway at similar speeds, even in hotter ambient temps.

Granted, I do run a 35/65 coolant to water ratio with 2 bottles of Kool-It additive in the summer, but that will only have a minor effect on coolant temps.
 


TyphoonFiST

9000 Post Club
Premium Account
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7,986
Location
Rich-fizzield
#18
That IS high, as my factory radiator never even sees near 200*F on the highway at similar speeds, even in hotter ambient temps.

Granted, I do run a 35/65 coolant to water ratio with 2 bottles of Kool-It additive in the summer, but that will only have a minor effect on coolant temps.
I run some NANO additive in my just for shits as it was on Clearance and it could only help....I roll usually 195*-200* also. Maybe we just got lucky or the additives really work!
 


Messages
101
Likes
54
Location
Cherry Hill, NJ
#19
I’m thinking of picking up a Mountune as well. I did some autocrossing a couple of weeks ago and the car kept creeping up to 225 between runs. I had to turn on the heat to bring it down. And it hovered around 220 on the whole highway drive back home.

Did you replace the thermostat as well?


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