Track Time Limited due to High CHT

TX-2019-Black_GT

Well-Known Member
Joined
Jul 3, 2020
Threads
0
Messages
61
Reaction score
19
Location
Texas
First Name
Dan
Vehicle(s)
2019 Mustang GT A10, Shadow Black with Black Trim Pkg.
It took me a Diff cooler, bigger radiator, manual trans air scoop ( shifts still got sloppy at end of sessions—I’m sure I was overheating it). In addition to oil cooler

And even then, it was the ragged edge.

In auto’s case, add a monster trans cooler.
I don't think the A10 needs more cooling. Mine has never gotten over 210-215. Heck, it takes it forever to even get to 190 in normal driving.

 
OP
OP

67Fast_V

Well-Known Member
Joined
Sep 1, 2021
Threads
5
Messages
119
Reaction score
47
Location
FL
Vehicle(s)
2020 Mustang GT PP1 A10, 1967 Fastback 460ci+
I’ve been thinking a good portion of the issue with your the A10 is the ability to keep revs over 6500 more of the time, combined with the added heat load of the automatic.

The amount of heat load generated from 0-6500 is drastically different than from 6500-7250

I think you’ll find as you get faster. Your radiator duct work and hood vents are a good start but not the complete fix.
@Never - I agree. RPM makes a huge difference. I bought the A10 so I could keep rpm high to improve acceleration. My plan is to shift at 7000-7200 every gear. 3rd - up into 7th. Doubt I will make it out 7th. Car is good for maybe 145 mph on my local tracks (so that's 7th). Best to date is 140 mph.

Now does that extra 700 rpm matter w/ my skill level ... no it doesn't. But I want to see what the car can do, even w/ my lousy driving. However 7200 rpm shifts need cooling and clearly this won't be easy. Will run my sealing + fan shroud mod on Nov 14 and we'll go from there. Hood vent is coming next.

@TX - thanks for the input. Just a few quick thoughts. As mentioned above, rpm increases the heat load drastically. I paddle shift mine. I think if you let the rpm increase above 5500 rpm, you will see CHT increase significantly.

Since you removed the stock oil cooler and went air-oil, the computer calculation for oil temp is no longer accurate. You will have to install a Tc in the oil line to know the temp.

The max A10 trans temp recommended by an experienced Forum member Flyhalf is 230F. He's gone through a few transmissions and is very fast, so I trust his judgement and experience.

The grill mod is a good one. 65-70% of the available dP across the cooling system is burned across the grill. And to add to that, the engine pulls air downstream of the grill and hence we are losing 65-70% of the ram air benefit. The OEM meters the flow at the inlet to control the total flow cus their system is very leaky and they want in general to minimize front end lift. More air more lift..

In the end, it's a large production passenger car and you have to expect design features like that. At some point, I will open my grill but not now. I want to use the available air that is already coming through the grill and if that is not enough, I will open it up.

Another tid bit, the engine at WOT and 7200 rpm drops the airflow to the radiator by 9%. That's right, you lose a good chunk of cooling when you really need it. This surprised me but it's real. Another OEM design compromise. Terrible. I will be undo'ing that one when it's time for more power. 2 for 1. More cooling and more power w/ 1 mod.

If you decide to let the rpm increase, I would recommend that you seal the perimeter of the radiator (you can read a few previous posts to see what that does). Good luck.
 

Cobra Jet

Well-Known Member
Joined
Feb 12, 2015
Threads
632
Messages
12,360
Reaction score
15,769
Location
NJ
Vehicle(s)
2018 EB Prem. w/PP and 94 Mustang Cobra
OP
OP

67Fast_V

Well-Known Member
Joined
Sep 1, 2021
Threads
5
Messages
119
Reaction score
47
Location
FL
Vehicle(s)
2020 Mustang GT PP1 A10, 1967 Fastback 460ci+
Not sure if this will be helpful, but I posted this back in 2019 - TSB 19-2049 from Ford - faulty CHT sensors in 5.0’s:
https://www.mustang6g.com/forums/threads/tsb-19-2049-cht-mil-dtc’s-p1289-or-p017d.120216/

I know OP doesn’t have a 2019, but that’s not to say that a faulty CHT doesn’t exist in 2020+…
Thanks CJ. Yes, possible. Haven't seen those codes, just the normal over temp P0217 and P0298. CHT runs normal values on the street. Actually a bit too cold at 175-185F now w/ 17O t-stat and radiator sealing. Very stable and repeatable readings. Nothing erratic. Just appears to have a heat load sensitivity.
 

ICU812

Banned
Banned
Banned
Joined
Apr 21, 2021
Threads
40
Messages
1,972
Reaction score
1,970
Location
Prestonburg,KY.
Vehicle(s)
Ford Tempo, Ford Mustang,FFR,Crown vic.
Take the exhaust manifolds/headers off and lead pipes with converters off, and have them ceramic coated.
Underhood temps on an other vehicle dropped 100*f , easier to cool the powerplant if it isn't baking in a hot room.
 


ice445

Well-Known Member
Joined
Apr 13, 2020
Threads
24
Messages
4,333
Reaction score
4,608
Location
Salt Lake City, UT
First Name
Ryan
Vehicle(s)
2020 Mustang GT 6MT
Thanks for finding the temps for me. The digging I found was 185F for the low speed. I figured 190 (+10 from stock thermostat) would do it. Called test off at 210F. Tomorrow I will let it go to 215 CHT and see if they come on. I don't understand why Ford would let it get that sporty (+32F from T-stat opening). Why let it thermal cycle that much.

I agree on the sealing. Pretty important. I'm about 80%. Some area are hard to chase out. Plus I wanted a little cold air to wash over the horn box on the left lower corner and then I put a dedicated hole in my sealing plate on the right upper corner to direct some flow to the fuse box and other electrical components on that side Now is that cold airflow truly needed, I'm not sure. I'm pleased closing off about 100 in^2 worth of "leaks". That's eqv to roughly 30% of the PP1 radiator open area.
Thermostats don't fully open at their rated temp, they just start to. A 180F thermostat is usually fully open by 192 or so. The fans don't need to run most of the time because the car in motion passes enough airflow over the rad to cool effectively, so they're basically reserved for idle or low speed situations which is why they come on relatively late.
 

NeverSatisfied

Well-Known Member
Joined
Apr 8, 2020
Threads
18
Messages
279
Reaction score
207
Location
Pittsburgh
First Name
Matt
Vehicle(s)
2021 GT 6MT Base
@Never - I agree. RPM makes a huge difference. I bought the A10 so I could keep rpm high to improve acceleration. My plan is to shift at 7000-7200 every gear. 3rd - up into 7th. Doubt I will make it out 7th. Car is good for maybe 145 mph on my local tracks (so that's 7th). Best to date is 140 mph.

Now does that extra 700 rpm matter w/ my skill level ... no it doesn't. But I want to see what the car can do, even w/ my lousy driving. However 7200 rpm shifts need cooling and clearly this won't be easy. Will run my sealing + fan shroud mod on Nov 14 and we'll go from there. Hood vent is coming next.
One thing to consider is the stock torque curve. Especially if not running a GT350 intake. With the closely spaced gears of the A10, that last 750RPM you're spinning the motor is falling further off the torque peak. Making extra noise and heat may not necessarily translate to faster lap times in a stock A10 GT.
 

Ewheels

Well-Known Member
Joined
Apr 5, 2019
Threads
57
Messages
1,222
Reaction score
1,369
Location
SoCal
First Name
Eric
Vehicle(s)
2018 GT PP1
Vehicle Showcase
1
Are those from Racelouvers an exact design replica type of the real GT4?
No, different design but similar and serve the same purpose.
Race Louvers does wind tunnel test their vents so the numbers they claim are factual.
 

Performance nut

Well-Known Member
Joined
Feb 10, 2015
Threads
172
Messages
1,668
Reaction score
639
Location
TX
Vehicle(s)
2018 Mustang GT A10
Vehicle Showcase
1
Take the exhaust manifolds/headers off and lead pipes with converters off, and have them ceramic coated.
Underhood temps on an other vehicle dropped 100*f , easier to cool the powerplant if it isn't baking in a hot room.
You're the first person I have seen recommend this. Not faulting your logic but I am curious if you or someone you know has done this. I ask because of a few things
  1. Few ever mess with the stock stuff. Most say rip it out and go straight to headers no cats. Not saying that's wrong for a full race setup, just nice to see an option for us mortals. 😁
  2. I didn't realize you could ceramic coat cats. Whereas cats need heat, I have always read this will overheat the matrix and cause issues.
  3. I would think you would want to get rid of the flex portion so I would assume some level of exhaust replacement would be necessary.
  4. Is it a good idea to coat the stock piping? I'm not 100% on the alloy used and curious it's resistance to corrosion and what will happen when the interior gets hotter.
 

ICU812

Banned
Banned
Banned
Joined
Apr 21, 2021
Threads
40
Messages
1,972
Reaction score
1,970
Location
Prestonburg,KY.
Vehicle(s)
Ford Tempo, Ford Mustang,FFR,Crown vic.
You're the first person I have seen recommend this. Not faulting your logic but I am curious if you or someone you know has done this. I ask because of a few things
  1. Few ever mess with the stock stuff. Most say rip it out and go straight to headers no cats. Not saying that's wrong for a full race setup, just nice to see an option for us mortals. 😁
  2. I didn't realize you could ceramic coat cats. Whereas cats need heat, I have always read this will overheat the matrix and cause issues.
  3. I would think you would want to get rid of the flex portion so I would assume some level of exhaust replacement would be necessary.
  4. Is it a good idea to coat the stock piping? I'm not 100% on the alloy used and curious it's resistance to corrosion and what will happen when the interior gets hotter.
Some of us can't legally remove the cats or run aftermarket headers, or in my case want too, because of class rules. or sleeper vibe to hide what it can do, at events that are taboo to talk about .
I had the exhaust manifolds extrude honed and then coated, the header pipes coated, the cats heat shields coated and pipe/tubing that is part of the oem cat pipe coated, Sorry I should have stated the cat case itself was not coated.
This was in a '88 Mercury, grand mark 302 v8 (347 with exployer v8 heads in reality :wink: ).
Later we added small duct work that went in between the cat and the cat's heat shield, and pushed the hot air out and under the car , duct was fed from an air pump if you bothered to look it was clear as day, but most didn't look.
This car also had a stock tank and a circle track fuel cell in that huge truck, for those late night banshe runs from Boston area to Detroit . You could do 100+ the whole way with 5 people in the car and a full trunk. only down side was it was thirty at those speeds.
 
OP
OP

67Fast_V

Well-Known Member
Joined
Sep 1, 2021
Threads
5
Messages
119
Reaction score
47
Location
FL
Vehicle(s)
2020 Mustang GT PP1 A10, 1967 Fastback 460ci+
One thing to consider is the stock torque curve. Especially if not running a GT350 intake. With the closely spaced gears of the A10, that last 750RPM you're spinning the motor is falling further off the torque peak. Making extra noise and heat may not necessarily translate to faster lap times in a stock A10 GT.
Hi Never - to your point, I ran a calculation to determine the impact of shifting at 6500 rpm vs. 7200.

I have a little analysis I put together when I was trying to decide which tranny to get (A10 or M6). I took the Coyote torque and HP curves and basically simulated a run down a straight away (apex speed to max speed). I would average the torque and HP over that speed range as you would shift through the gears and compare doing that with a M6 vs. A10. All stock including tires. As you know, I picked the A10 as my horse.

For this shift point evaluation, I used 63-140 mph. So that's 3rd gear at the apex and shifting into 7th and topping out at 140 mph. Here are the results w/ no transmission or driveline losses included in either case. The magnitude is off since no losses are included but the relative difference between the shift points are valid. See below for the results. Better to shift higher if cooling allows. Cheers.

7200 rpm shift Point:
Ave Torque = 2044 ft-lbs
Ave Power = 454.6 hp

6500 rpm shift Point:
Ave Torque = 1948 ft-lbs (-4.7%)
Ave Power = 435.7 hp (-4.2%)
 

bnightstar

Well-Known Member
Joined
Mar 15, 2019
Threads
14
Messages
1,627
Reaction score
698
Location
Bulgaria
First Name
Hristofor
Vehicle(s)
2013 Ford Fiesta 1.25i, 2017 GB Ford Mustang GT PP Premium
Vehicle Showcase
1
Better to shift higher if cooling allows. Cheers.

7200 rpm shift Point:
Ave Torque = 2044 ft-lbs
Ave Power = 454.6 hp

6500 rpm shift Point:
Ave Torque = 1948 ft-lbs (-4.7%)
Ave Power = 435.7 hp (-4.2%)
Question is how much of this difference and we are talking 20 hp here is going to be lost because of overheating. Also last time I checked Coyotes are not making linear power all the way to red line anyway or at least mine Gen 2 don't make much power after 6500 rpm anyway.
 

TundraOnKings

Well-Known Member
Joined
Jun 7, 2021
Threads
14
Messages
458
Reaction score
583
Location
PNW
First Name
T
Vehicle(s)
'20 GT PP1 A10, '20 Armada,'15 Tundra,14' GS350F
@Never - I agree. RPM makes a huge difference. I bought the A10 so I could keep rpm high to improve acceleration. My plan is to shift at 7000-7200 every gear. 3rd - up into 7th. Doubt I will make it out 7th. Car is good for maybe 145 mph on my local tracks (so that's 7th). Best to date is 140 mph.

Now does that extra 700 rpm matter w/ my skill level ... no it doesn't. But I want to see what the car can do, even w/ my lousy driving. However 7200 rpm shifts need cooling and clearly this won't be easy. Will run my sealing + fan shroud mod on Nov 14 and we'll go from there. Hood vent is coming next.

@TX - thanks for the input. Just a few quick thoughts. As mentioned above, rpm increases the heat load drastically. I paddle shift mine. I think if you let the rpm increase above 5500 rpm, you will see CHT increase significantly.

Since you removed the stock oil cooler and went air-oil, the computer calculation for oil temp is no longer accurate. You will have to install a Tc in the oil line to know the temp.

The max A10 trans temp recommended by an experienced Forum member Flyhalf is 230F. He's gone through a few transmissions and is very fast, so I trust his judgement and experience.

The grill mod is a good one. 65-70% of the available dP across the cooling system is burned across the grill. And to add to that, the engine pulls air downstream of the grill and hence we are losing 65-70% of the ram air benefit. The OEM meters the flow at the inlet to control the total flow cus their system is very leaky and they want in general to minimize front end lift. More air more lift..

In the end, it's a large production passenger car and you have to expect design features like that. At some point, I will open my grill but not now. I want to use the available air that is already coming through the grill and if that is not enough, I will open it up.

Another tid bit, the engine at WOT and 7200 rpm drops the airflow to the radiator by 9%. That's right, you lose a good chunk of cooling when you really need it. This surprised me but it's real. Another OEM design compromise. Terrible. I will be undo'ing that one when it's time for more power. 2 for 1. More cooling and more power w/ 1 mod.

If you decide to let the rpm increase, I would recommend that you seal the perimeter of the radiator (you can read a few previous posts to see what that does). Good luck.
Sounds like we drive, very much of the same.
Which might explain our heat issues.
My last track-day with a very experienced Mustang track-instructor, he kept telling me to stay in a higher gear around a few of the corners. I wanted to be in 3rd, exiting corners with immediate throttle response at 6500RPM’s, he was suggesting I stay in 4th, but the exit felt like I was losing so much speed in the 5000RPM range.
It definitely would’ve kept me a bit cooler staying in 4th, but also slower, in my opinion.
Great info in this thread, thank you all for posting.
I really didn’t want to chop up my hood, but I think I might have to. Along with coolers.
Hard to believe someone mentioned they couldn’t overheat an A10.

From the few tracks I’ve been on, engine-oil overheated easier on the more open (12 turns 1.97mi) track where I’m at 130mph front and back stretch (twice in a 1:35 lap time) and then in the waaaay more technical, shorter track with lots of elevation, 3 straights at ~ 100mph each (2:00 track time) 16 turns 2.3mi, I was overheating rear diff and trans, before engine oil. I haven’t been back to this track after wrapping exhaust and moving to 75w-140BG fluid. But I have been to the faster track, and rear diff issue was eliminated entirely. I was very surprised.

F1BD1750-DBCA-451E-A6B7-FC0FD31D581D.png
 
Last edited:

NeverSatisfied

Well-Known Member
Joined
Apr 8, 2020
Threads
18
Messages
279
Reaction score
207
Location
Pittsburgh
First Name
Matt
Vehicle(s)
2021 GT 6MT Base
Hi Never - to your point, I ran a calculation to determine the impact of shifting at 6500 rpm vs. 7200.

I have a little analysis I put together when I was trying to decide which tranny to get (A10 or M6). I took the Coyote torque and HP curves and basically simulated a run down a straight away (apex speed to max speed). I would average the torque and HP over that speed range as you would shift through the gears and compare doing that with a M6 vs. A10. All stock including tires. As you know, I picked the A10 as my horse.

For this shift point evaluation, I used 63-140 mph. So that's 3rd gear at the apex and shifting into 7th and topping out at 140 mph. Here are the results w/ no transmission or driveline losses included in either case. The magnitude is off since no losses are included but the relative difference between the shift points are valid. See below for the results. Better to shift higher if cooling allows. Cheers.

7200 rpm shift Point:
Ave Torque = 2044 ft-lbs
Ave Power = 454.6 hp

6500 rpm shift Point:
Ave Torque = 1948 ft-lbs (-4.7%)
Ave Power = 435.7 hp (-4.2%)
Credit to you for doing the work--it'd be interesting to look at the analysis over an entire lap.

In desperation as I was fighting through my issues a couple years ago, I spoke with Vorshlag about the 2018 they developed. They had the same heat generation challenges at 6500+. They found short shifting at times to stay closer to torque peak resulted in faster laps for them and significantly less heat problems in their 6MT.

I still ripped mine to 7250 for every shift once I had it loaded up with coolers and vents.
 

Egparson202

Well-Known Member
Joined
Jul 28, 2021
Threads
0
Messages
388
Reaction score
358
Location
USA
Vehicle(s)
2019 Shelby GT350, 2018 Audi TTRS
Question is how much of this difference and we are talking 20 hp here is going to be lost because of overheating. Also last time I checked Coyotes are not making linear power all the way to red line anyway or at least mine Gen 2 don't make much power after 6500 rpm anyway.

Good counter-point. :thumbsup:

The surest way to solve this riddle is to break out the stop watch. That’s right, folks. Calculations are a great place to start. But as my uncle was fond of saying, the stop watch doesn’t lie. Who’s up for a little experimentation?
 
Last edited:

 
51 - American Racing Headers - 1
Top