CHT’s - Gen1 Coyote, Supercharged (15 PSI), Cooling Upgrades

So, cruising along (100-130 MPH) in 101°F weather for about 10 miles. CHT at about 235°F.

What is too high (250°F I assume), and how can I improve them? Yes, on a track.

A CHT of 250*F (120*C) is usually the beginning of the H zone on the gauge where imminent engine damage is likely. I'd be uncomfortable with any sustained CHT above 220*F (105*C) on an all aluminium engine so it sounds like you need cooling system upgrades.
Since your engine runs hot at highway speeds, you definitely need to upgrade the radiator to a thicker all aluminium unit.
Since you have a Coyote engine, you might also want to consider the MMR head cooling mod, though it's best done with the engine out. The no.8 cylinder on all Ford 4V engines tends to run hotter than the 2V or 3V because the cooling jacket around the combustion chamber is smaller to accommodate the extra exhaust valve, in addition to being the cylinder furthest away from the water pump. The MMR head cooling mod joins the cooling jackets at the back of both heads to equalize the temperature.
Your engine has forced induction so you might need to upgrade the intercooler or the intercooler pump (if water cooled) if the IATs are far above ambient temperature.
For track use, you might need to consider adding an oil cooler and a higher capacity oil pan.
You can improve the efficiency of the electric cooling fan, and reduce underhood temperatures, by adding '13 GT500 style hood vents near the front of the hood. At high speeds, the negative air pressure generated in that area will suck the hotter air out of the engine compartment.

Dino Dino Bambino said:

Since your engine runs hot at highway speeds, you definitely need to upgrade the radiator to a thicker all aluminium unit.

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I did that as part of my initial upgrade to FI.

Dino Dino Bambino said:

Since you have a Coyote engine, you might also want to consider the MMR head cooling mod, though it's best done with the engine out.

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Considered that, and was told it wouldn’t actually help me achieve anything. I’ll reconsider it.

Dino Dino Bambino said:

Your engine has forced induction so you might need to upgrade the intercooler or the intercooler pump (if water cooled) if the IATs are far above ambient temperature.

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I did that upgrade at initial FI install. Never went with the minimum parts used in the kit. Bought all that beforehand & installed from the jump.

Dino Dino Bambino said:

For track use, you might need to consider adding an oil cooler and a higher capacity oil pan.

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Already have an oil cooler, not really running track events. Just wanted to open it up for fun. That’s the only time I’ve done that.

Dino Dino Bambino said:

You can improve the efficiency of the electric cooling fan, and reduce underhood temperatures, by adding '13 GT500 style hood vents near the front of the hood. At high speeds, the negative air pressure generated in that area will suck the hotter air out of the engine compartment.

Click to expand...

I already have upgraded to the GT500 hood, and the GT500 fan. did this at same time as all the other upgrades.

Wow, you've already done almost everything I suggested. Apart from removing the front grille '13 GT500 style to increase airflow through the radiator, the only other thing I can suggest that'll definitely make the engine run cooler is to feed it E85.

crjackson said:

Considered that, and was told it wouldn’t actually help me achieve anything. I’ll reconsider it.

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I've heard mixed reviews about the MMR head cooling mod. Some believe it only has a placebo effect so I think that requires further research.

Not boosted and never monitored CHTs on track. I figured the pcm would warn me if too high, and go into limp mode.
Now oil temp I am keeping an eye on. On a 40 min session, it reached as high as 285*F. The boss oil cooler did not make a noticable difference, so I removed it.

Have you ever considered increasing coolant flow with an electric water pump? I swear my temp factory temp gauge is down a notch from where my stock pump keeps my car. I have a mechanical in there now and the needle sits straight up and down. When I was running my electric it was always tilted to the left.

I have my warning light set for 250° (Gen 2 swapped SN95/Holley EFI) and that’s when I start rolling cool down laps.

This has been discussed at great length over on TMO and where I drew my conclusion from.

Here is a good compilation of those posts:
https://www.google.com/search?q=cyl...CmcQrQIoBHoECAcQBQ&biw=390&bih=778&dpr=3#ip=1

Gratuitous picture:

07 Boss said:

Have you ever considered increasing coolant flow with an electric water pump? I swear my temp factory temp gauge is down a notch from where my stock pump keeps my car. I have a mechanical in there now and the needle sits straight up and down. When I was running my electric it was always tilted to the left.

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I was thinking about that. I’ve wondered if that would help any.

white95 said:

Here is a good compilation of those posts:

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Thanks, I’ll have a look.

Okay, some cursory reading done. I don’t like the open grill look on the street at all, and there’s always construction going on around here. But I do see some boosted Mustangs (mostly GT500’s) running around with open grills, so it must help.

I have been eyeballing the Roush lower grill to help keeping my HX cool and preventing power loss. It looks like doing both upper/lower Roush high-flow grills, and possibly an electric water pump may be my next upgrades.

However, from what I’ve read from the links above, it sounds like 235° isn’t really a big deal. That’s good to know, but I’d still like to lower it for good measure. I guess a Roush grill-attack is next.

Dino Dino Bambino said:

Wow, you've already done almost everything I suggested. Apart from removing the front grille '13 GT500 style to increase airflow through the radiator, the only other thing I can suggest that'll definitely make the engine run cooler is to feed it E85

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Yeah, I thought it out pretty well before boosting. I was always planning on the Roush high-flow grills, but held off because I love my grill-mounted fog lights. I guess it’s time to let that go.

There is no E85 in my area, and I have no love for it anyway. Not going there.

I’m going to look into an electrical water pump too. Also as a last resort, I’ll probably see if I can find an impossibly gigantic radiator that can be shoehorned in there too.

I just ordered:
Roush High Flow Upper Grill
Roush High Flow Lower Grill
Roush Lower Valance Fog Lights

Maybe this will boost my airflow and help out a little.

A bit of an old thread, but I noticed I failed to followup on my results.

I installed both the Roush Upper/Lower Hi-Flow grills, and relocated the fogs using the Roush kit.

Wow! This really turned things around, A LOT! My temps stay under 210°F no matter how I drive, or how hot it is. Truly astonishing results. Most of the time I’m at 198°F - 205°F. I hope it stays this way.

I guess airflow was my issue.

Thought about taking mine on a road course, maybe once for S &G, but I don't have any of those upgrades.
So that pretty much seals the deal as a "not ever happening", especially since I am auto on top of everything else.
Thanks for the update.