Ford Focus ST Forum banner

1 - 20 of 39 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter #1
Hi,

I was wondering if anyone had tried something similar?
I'm running a stage 3 tune on my 2013 Focus ST. I had no trouble driving it normally but the coolant temp can get to boiling temperature on a relatively fast faced drive, but cools down quickly when I go easy on the throttle.
I've had overheating problems during track days when I was still running stage 1 tune and hardware. After a FMIC, exhaust, and stage 3 tune, it seems to overheats even during mountain runs which never happened to me before.

So i was looking for solution to this overheating problem.
1. cutting out the grille wasnt going to work for my car, ASDM model, the number plate holder is molded in as part of the grille. Unless I would buy a ASDM grille for this.
2. Grill shutter had its fins ripped off.
3. Oil cooler, one possible way to tackle this.
4. Adding 2 extra slim rad fans on top of the intercooler to push air into the radiator?

Any other suggestions?
 

·
Premium Member
Joined
·
526 Posts

·
Registered
Joined
·
275 Posts
What percentage of radiator fluid to water are you running in it? The higher the % of radiator fluid to water, the worse it transfers heat from the engine and also sheds that heat in the radiator. If you can, run a lower % of radiator fluid to water. Are you located in an area where it doesn't get below freezing hardly ever? Water is a better heat transfer agent than ethylene glycol, but you do have to keep some eg in it for corrosion resistance, and if you're where it gets below freezing, to keep it from freezing solid.

You could also try one of the "water wetter" type products that help the coolant transfer heat better.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #5
What percentage of radiator fluid to water are you running in it? The higher the % of radiator fluid to water, the worse it transfers heat from the engine and also sheds that heat in the radiator. If you can, run a lower % of radiator fluid to water. Are you located in an area where it doesn't get below freezing hardly ever? Water is a better heat transfer agent than ethylene glycol, but you do have to keep some eg in it for corrosion resistance, and if you're where it gets below freezing, to keep it from freezing solid.

You could also try one of the "water wetter" type products that help the coolant transfer heat better.
I wasnt measuring but it was close to 50% mixture. I'm not sure if the coolant was the problem here, it has been flushed and replaced complete since my last track day when it overheated. 25 degree Celsius in my country is considered a very cold day. :LOL::LOL:

Its either the small opening on the grille that limits the air flow, or it just overwhelmed the radiator badly, getting one of those mountune radiators for my car in my country is stupidly expensive, shipping and taxes will pretty much double the price. So i try not to go that route.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #6
Bigger radiator, like this on: mountune Focus St Triple Pass Radiator Upgrade

Also, remove the active grill shutter completely.
The only thing left with the grill shutter, well, half of it, i cut the bottom half out for the bigger 3.5" thick mishimoto intercooler is the shroud that channels air towards the radiator. I tried running without the shroud, it overheated even worst than with it.

I suspect the way our cars works is that air are not so much of being fed in from the front grille, maybe rather it was sucked in when needed, all the active grille shutter and closed engine compartment, so i wonder if adding 1 or 2 additional radiator fan in front just on top of the intercooler can help draw more air in.

Also I was running the car without AC, I just noticed that the radiator fan only go up to around (monitored through cobb ap) 40% duty cycle @90 degree celcius as apposed to 80% duty regardless of the coolant temp with the AC on. Maybe I should have kept the AC on, just slightly to keep the rad fan running at full blast?
 

·
Registered
Joined
·
671 Posts
Don't forget that all fans become a restriction a certain speeds (what speed that is depends on the fan of course). This is why a lot of manufacturers turn fans off at certain speeds. Be careful adding fans. Leave shrouds and ductwork in place along with the underbelly pan (pressure and directional airflow has been engineered into the car from ford) but a HIGH QUALITY larger radiator itself as well as an oil cooler would help. Do not cheap out here.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #8
Don't forget that all fans become a restriction a certain speeds (what speed that is depends on the fan of course). This is why a lot of manufacturers turn fans off at certain speeds. Be careful adding fans. Leave shrouds and ductwork in place along with the underbelly pan (pressure and directional airflow has been engineered into the car from ford) but a HIGH QUALITY larger radiator itself as well as an oil cooler would help. Do not cheap out here.
Make sense, thats why I wonder if this idea would work. i'll have to test the car out and monitor the different radiator fan speed at higher speed to test this one out.

I'll try to source a good radiator, but i wonder if it will work as good as we thought it will. Thicker radiator tends to limit the air flow even more isnt it? With our limited air flow in front, wonder how much will that help with the car.
 

·
Registered
Joined
·
671 Posts
I'll try to source a good radiator, but i wonder if it will work as good as we thought it will. Thicker radiator tends to limit the air flow even more isnt it? With our limited air flow in front, wonder how much will that help with the car.
Your thought process is on track here, and i wish i had the answer you're looking for before you spend a large sum of money on a radiator. You already restricted airflow/ transferred more heat to the existing airflow by installing a larger intercooler. The thicker radiator will also be more of an airflow restriction than the stock one. But how well that radiator manages heat is what will make or break your overheat situation. A definite benefit is the added coolant capacity, which gives you more coolant availble to absorb energy. I think the stock system only holds 5 quarts of coolant, which is way too little for something that has to manage so much heat.

The idea of an external oil cooler does two things, one being it removes something that the radiator coolant has to work to cool down, the other being it gives you the option to mount a cooler in an area that wouldnt block the radiator.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #10
Your thought process is on track here, and i wish i had the answer you're looking for before you spend a large sum of money on a radiator. You already restricted airflow/ transferred more heat to the existing airflow by installing a larger intercooler. The thicker radiator will also be more of an airflow restriction than the stock one. But how well that radiator manages heat is what will make or break your overheat situation. A definite benefit is the added coolant capacity, which gives you more coolant availble to absorb energy. I think the stock system only holds 5 quarts of coolant, which is way too little for something that has to manage so much heat.

The idea of an external oil cooler does two things, one being it removes something that the radiator coolant has to work to cool down, the other being it gives you the option to mount a cooler in an area that wouldnt block the radiator.
To mount the external oil cooler, might just shave off part of the grill and move it else where.

I thought of a bigger reservoir, but doesnt seems like its that readily available as well.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #11
Has anyone replaced their coolant reservoir with something universal and bigger? or add a second reservoir perhaps?
 

·
Registered
Joined
·
671 Posts
When i was referring to larger cooling capacity, i was taking into consideration where the additional coolant was sitting (in the radiator). If you just have a larger resevoir, you might actually delay the coolant temperature recovery time after a run, because the stock radiator can only shed so much energy, but now has the job of shedding it from a lot more coolant. So the time it takes to overheat might be extended a little bit, but it's still going to happen and going to take even longer to stabilize.
 

·
Registered
Joined
·
1,738 Posts
Has anyone replaced their coolant reservoir with something universal and bigger? or add a second reservoir perhaps?
mishimoto makes an aftermarket reservoir for us but no mention of it increasing volume. They do say its baffled but otherwise its mostly a visual improvement:
 

·
Premium Member
Joined
·
13,294 Posts
mishimoto makes an aftermarket reservoir for us but no mention of it increasing volume. They do say its baffled but otherwise its mostly a visual improvement:
It is larger. I have one on my car.

The Mountune rad is a triple pass. Which means the coolant passes through the rad more time before heading back to the engine. It allows for better cooling. Combining this with the information I posted above about the oil cooler does help. Also making sure you have good ducting to keep air from spilling over also drastically helps. If you still don't think you don't have enough air flow then it's time to delete the A/C system as the cooler for that sits fully in front of the radiator.

Sent from my ONEPLUS A6013 using Tapatalk
 

·
Registered
Joined
·
275 Posts
I wasnt measuring but it was close to 50% mixture. I'm not sure if the coolant was the problem here, it has been flushed and replaced complete since my last track day when it overheated. 25 degree Celsius in my country is considered a very cold day. :LOL::LOL:

Its either the small opening on the grille that limits the air flow, or it just overwhelmed the radiator badly, getting one of those mountune radiators for my car in my country is stupidly expensive, shipping and taxes will pretty much double the price. So i try not to go that route.
If 78 F/26 C is a cold day in your area, then I would run a 90/10 or 80/20 ratio of water to antifreeze. If you're running 50/50 then you're running much more antifreeze than you need, and it likely is causing it to not cool as effectively. Quest for the Ideal Coolant Ratio

If you go with the 90/10 or 80/20 ratio and it's still not helping as much as you'd like, then grab one of the coolant additive products as a lot of folks have tested them to show they help with cooling. Here's an example: http://www.superstreetonline.com/how-to/engine/0703-turp-cooling-system-additives/

IMO, it would be a lot less expensive to at least try the coolant ratio change (could just drain most of it out and then refill with distilled water) and add a bottle of coolant additive. If it doesn't then you're out maybe $20 in items... If that does the job without spending several hundred on a radiator, then great. By my calculations, if you're running a 50/50 mix now, you'd need to drain out 5.7 liters of it and then refill with distilled water to get to a 88/12% ratio of water to radiator fluid. Taking out 5.45 liters (thus leaving 1 liter of mix in the car) and refilling with water would give you an 84/16% ratio.... Just play with the math and drain/replace what you think will work well for you in your climate.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #16
It is larger. I have one on my car.

The Mountune rad is a triple pass. Which means the coolant passes through the rad more time before heading back to the engine. It allows for better cooling. Combining this with the information I posted above about the oil cooler does help. Also making sure you have good ducting to keep air from spilling over also drastically helps. If you still don't think you don't have enough air flow then it's time to delete the A/C system as the cooler for that sits fully in front of the radiator.

Sent from my ONEPLUS A6013 using Tapatalk
Ohhhh deleting the A/C will probably kill me in our climate over here lol. 30 to 35 deg celcius over here is a normal day.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #17
If 78 F/26 C is a cold day in your area, then I would run a 90/10 or 80/20 ratio of water to antifreeze. If you're running 50/50 then you're running much more antifreeze than you need, and it likely is causing it to not cool as effectively. Quest for the Ideal Coolant Ratio

If you go with the 90/10 or 80/20 ratio and it's still not helping as much as you'd like, then grab one of the coolant additive products as a lot of folks have tested them to show they help with cooling. Here's an example: http://www.superstreetonline.com/how-to/engine/0703-turp-cooling-system-additives/

IMO, it would be a lot less expensive to at least try the coolant ratio change (could just drain most of it out and then refill with distilled water) and add a bottle of coolant additive. If it doesn't then you're out maybe $20 in items... If that does the job without spending several hundred on a radiator, then great. By my calculations, if you're running a 50/50 mix now, you'd need to drain out 5.7 liters of it and then refill with distilled water to get to a 88/12% ratio of water to radiator fluid. Taking out 5.45 liters (thus leaving 1 liter of mix in the car) and refilling with water would give you an 84/16% ratio.... Just play with the math and drain/replace what you think will work well for you in your climate.
Come to think of it, its been running hotter after i flushed my coolant with 50/50 mix. Well, I have the redline waterwetter in order. Probably gonna flush the whole system and replace the coolant with it and see if it helps with the temps. Its 10am here today, and the coolant temp was sitting around 90 to 92 deg celcius on the way to work.
 

·
Registered
Joined
·
275 Posts
The thermostat in the car is a 195 F unit, I think, but somebody correct me if I'm wrong. If so, 90 C is the normal operating temp. How much is it going up to when you're hammering on it? I've seen mine go up over 210 F when climbing mountains around here (11,000' pass), but it comes down quickly once I start going down the other side.
 

·
Registered
Joined
·
22 Posts
Discussion Starter #19
The thermostat in the car is a 195 F unit, I think, but somebody correct me if I'm wrong. If so, 90 C is the normal operating temp. How much is it going up to when you're hammering on it? I've seen mine go up over 210 F when climbing mountains around here (11,000' pass), but it comes down quickly once I start going down the other side.
It went up to 113 - 115 deg celcius, but quickly cooling down after i take a bit of pace off.
The car will go into limp mode once it hit 120 deg c or so. At least with cobb stage 3 tune.
 

·
Registered
Joined
·
275 Posts
Oh yeah... That's way too hot. If the radiator coolant ratio change doesn't help enough then definitely look at a larger radiator core.
 
1 - 20 of 39 Posts
Top