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S550 Stasik_a4 Down Under Build Build Thread Profile - S550 Mustangs

88
148
Exp. Level
5-10 Years
Australia
Glycol based Coolants (antifreeze) retains heat. Good for winter but bad for heat rejection. It will raise the boiling point some but in extreme duty situations can’t reject the heat fast enough. Race tracks also don’t like it because it makes the track super slippery when spilled on the racing surface. Distilled water and water wetter is good. I ducted air to the cooler but tried not to rob it from the radiator, so straight ducting.
I'll have to look into running the distill water and water wetter instead of coolant. You still running thermostat in yours?
Will have to look into the FP350S ducting that I'm running and see if it has closed off any airflow.
 
5,768
6,908
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
I'll have to look into running the distill water and water wetter instead of coolant. You still running thermostat in yours?
Will have to look into the FP350S ducting that I'm running and see if it has closed off any airflow.
No thermostat. I have an electric water pump.I warm the motor with the pump off then flick it on after a minute or so. This is a race only car so no restrictions in either the airflow or water flow to keep things as efficient as I can.
 
5,768
6,908
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Forgive me but I’m not well versed in the requirements and limitations of the s550 but looking at the face of the radiator, there seems to be very little area where air can pass straight through without having to first pass through or around either the oil cooler, ac condenser or other ducting. From what I can see it also looks like air can spill around the sides and top of the ducting, effectively bypassing the radiator entirely. Perhaps @PaddyPrix or @steveespo will share some of their s550 experience with us.

FE7D894A-A8B3-4DDF-8589-4ABD307B8F26.jpeg
 
I run mid 230s in COTA in 100* heat - COTA is harder on cars (and especially engines) than any track I've run at. I've seen head temps like you're seeing once before - and it was while I was chasing down a bad heater core/bypass design. Have you modified that at all?

Regarding the ducting, the ducting @stasik_a4 is running was designed by Ford Performance themselves for the FP350S - it's the same stuff I run and is very, very robust. The air gap between the cooler and radiator is there by design. I wouldn't change that, personally.

My guess is one of three things:
  1. A heater core bypass is causing issues (either bypassing too much water or air trapped)
  2. The lack of airflow out the hood - you definitely want to add at least the big center Hood Louvres vent
  3. The ducting isn't sealing too the front bumper well enough and airflow is going around the gaps. Since the FP350S ducting was designed for a GT350 front bumper, I could see there being some small fitment issues in how it seals to the bumper cover
 
Last edited:
5,768
6,908
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Regarding the ducting, the ducting @stasik_a4 is running was designed by Ford Performance themselves for the FP350S - it's the same stuff I run and is very, very robust. The air gap between the cooler and radiator is there by design. I wouldn't change that, personally.
That may be, I would love to hear the logic behind covering 90% of the radiator surface and intentionally leaving a gap between the cooler and radiator.....these things are generally not considered to be advantageous. Maybe there's something I'm missing here....but what?
 
88
148
Exp. Level
5-10 Years
Australia
That may be, I would love to hear the logic behind covering 90% of the radiator surface and intentionally leaving a gap between the cooler and radiator.....these things are generally not considered to be advantageous. Maybe there's something I'm missing here....but what?
So with mine, I don't have any gap as I still have the A/C condenser still there. I mounted my oil cooler then condenasor then radiator which is a mishimoto one.
The oil cooler ducting I had to trim alot to make it fit and work with the gt bumper bar as it was designed to work and fit 350 front.
20220619_120535.jpg20220619_123251.jpg20220619_123259.jpg20220619_123514.jpg20220619_123522.jpg
 
88
148
Exp. Level
5-10 Years
Australia
I run mid 230s in COTA in 100* heat - COTA is harder on cars (and especially engines) than any track I've run at. I've seen head temps like you're seeing once before - and it was while I was chasing down a bad heater core/bypass design. Have you modified that at all?

Regarding the ducting, the ducting @stasik_a4 is running was designed by Ford Performance themselves for the FP350S - it's the same stuff I run and is very, very robust. The air gap between the cooler and radiator is there by design. I wouldn't change that, personally.

My guess is one of three things:
  1. A heater core bypass is causing issues (either bypassing too much water or air trapped)
  2. The lack of airflow out the hood - you definitely want to add at least the big center Hood Louvres vent
  3. The ducting isn't sealing too the front bumper well enough and airflow is going around the gaps. Since the FP350S ducting was designed for a GT350 front bumper, I could see there being some small fitment issues in how it seals to the bumper cover
I have not modified any part of the cooling system... I was planning on doing the head cooling mod but after speaking with you, you said not to bother as it didn't make much difference. The only thing is I'm running Mishimoto bigger radiator and everything else is stock.

The ducting I had to trim to make it fit the standard gt bar and it sits fairly tight against the grill opening as I had to trim them also. I posted above.

I think the hood vents will be the next thing to look into.
 
So with mine, I don't have any gap as I still have the A/C condenser still there. I mounted my oil cooler then condenasor then radiator which is a mishimoto one.
The oil cooler ducting I had to trim alot to make it fit and work with the gt bumper bar as it was designed to work and fit 350 front.
View attachment 81442View attachment 81443View attachment 81444View attachment 81445View attachment 81446

Does it fight tight up against the bumper cover? Mine seals up tight using the weather stripping-type of stuff. It's also possible that your AC condenser isn't helping since it's taking up the gap between the cooler and radiator. Do you still have the stock heater core hoses?

That may be, I would love to hear the logic behind covering 90% of the radiator surface and intentionally leaving a gap between the cooler and radiator.....these things are generally not considered to be advantageous. Maybe there's something I'm missing here....but what?
This isn't my area of expertise/study, so this will be a bit of a guess based on limited knowledge. But my understanding is that air that enters the grill directly in front of the cooler is forced into the cooler (duct doesn't allow it anywhere else to go) and the "ramps" on the top/bottom increase the velocity of the air moving through the cooler. When mixed with the air moving through the righthand side of the grill and into the radiator directly (along with the gap), you get high velocity, even airflow through the radiator. that's my understanding.

I suspect the only way to know is with some pressure tests where you can measure airflow.

Either way, we know it's a proven design and works well
 
5,768
6,908
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Does it fight tight up against the bumper cover? Mine seals up tight using the weather stripping-type of stuff. It's also possible that your AC condenser isn't helping since it's taking up the gap between the cooler and radiator. Do you still have the stock heater core hoses?


This isn't my area of expertise/study, so this will be a bit of a guess based on limited knowledge. But my understanding is that air that enters the grill directly in front of the cooler is forced into the cooler (duct doesn't allow it anywhere else to go) and the "ramps" on the top/bottom increase the velocity of the air moving through the cooler. When mixed with the air moving through the righthand side of the grill and into the radiator directly (along with the gap), you get high velocity, even airflow through the radiator. that's my understanding.

I suspect the only way to know is with some pressure tests where you can measure airflow.

Either way, we know it's a proven design and works well
@captdistraction did some testing with this.....let's see if he chimes in.
I believe what he found was that allowing the air to get behind the cooler stalled the air trying to go through the cooler and that eliminating that gap forced the air to go through the cooler and also the radiator, which makes perfect sense to me. (high pressure flows to low pressure, high pressure into high pressure doesn't flow) I understand this is a ford performance part and is probably adequate. But that doesn't mean its optimum. We all know about how shortcuts are made for the sake of easy manufacturing happen.
 

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