What's your Cylinder Head Temp?

I'm pondering a radiator upgrade as I have the base model 1 inch radiator. However I need to establish a base line to determine if this is normal behavior or an indication of cooling capacity limits.

I'm running the following power train modifications for reference:

1. Levels Gen 3 Street IC
2. Boomba BOV
3. LMS 91 Octane Stage 3 v7 PCM software
4. Brisk RR14YS plugs
5. Green panel filter
6. LMS 160F Thermostat

Cylinder head temps some times hover around low / mid 170's during driving below 60mph, light load. Once I hit about 60 the upper portion of the grill shudders close and I hover around 180F~190F, which I would expect due to he lack of flow.

Now, when I step on it and start doing runs or driving hard on back roads, cylinder head temps are typically around 185~195. I have not yet reached 200 (stock car as it came off the lot would get up to about 210~215 just idling on hot days) even under sustained WOT with another passenger (about 400lbs total between the two of us).

I don't recall ever looking at cylinder head temps when I first got the car while driving WOT mostly because I was befuddled by the lack of power in 3rd gear the car used to have.

Rule of thumb (which I'm not a fan of, but it's all I have to go on) is that you can generally expect cylinder head / coolant temps to be 10 to 20 degrees above the thermostat set point. So I would generally expect cylinder head temps around 170~180. 190 seems a bit high based on that, but again I don't have a base line with EB engines. Any feedback is appreciated on what your all seeing, please list your modifications also so I have a general idea of how much power you car is putting out. Higher power modifications are going to inherently have higher losses.

I have the PP which as you know has the upgraded radiator. My CHT usually hover between 187-189 during steady state cruising at 70-80mph. The highest I've seen at idle has been 190 +/- 1. Unlike you I deleted my grill shutters when I did the intercooler install and I have the factory thermostat. I have noticed that on extremely hot and humid days here in Houston that when I get into the throttle that they shoot up rather quickly, I've never seen over 200 though.

Not exactly an apples to apples comparison though...

I was actually monitoring this yesterday evening due to having a conversation with a vendor about upgraded thermostats. Mine stays right around 180° most of the time. It'll fluctuate around 178°-183° and that seems to be the normal range, but it literally stays right at 180° for the most part. If I do a WOT pull or traverse a tall hill/mountain, it'll creep up to around 185°-186°. Even with all of my driving yesterday, it never reached a temp higher than 186°.

I have a tuned, bolt-on (stock thermostat) PP car with an upper and lower GT grille delete. I also have a Gen 1 Levels Street FMIC.

Edit: I forgot to add that a good portion of that driving yesterday was at speeds lower than 50 mph.

TEXAS HEAT said:

I have the PP which as you know has the upgraded radiator. My CHT usually hover between 187-189 during steady state cruising at 70-80mph. The highest I've seen at idle has been 190 +/- 1. Unlike you I deleted my grill shutters when I did the intercooler install and I have the factory thermostat. I have noticed that on extremely hot and humid days here in Houston that when I get into the throttle that they shoot up rather quickly, I've never seen over 200 though.

Not exactly an apples to apples comparison though...

Click to expand...

No, but it's information with context. Are you running a stock car or do you have other modifications? Sounds like right now I'm seeing temps nearly the same as you.

If I upgrade the radiator I won't do it until next year as fall is just around the corner and I need to stop spending money on this car...for a while ;-). But I would like to get an idea of what the next most critical change would be so I can keep an eye out for sales around Christmas / new years etc. However if my temps are par for the course then I won't bother as it would be a waste of money.

TheLion said:

No, but it's information with context. Are you running a stock car or do you have other modifications? Sounds like right now I'm seeing temps nearly the same as you.

If I upgrade the radiator I won't do it until next year as fall is just around the corner and I need to stop spending money on this car...for a while ;-). But I would like to get an idea of what the next most critical change would be so I can keep an eye out for sales around Christmas / new years etc. However if my temps are par for the course then I won't bother as it would be a waste of money.

Click to expand...

My mods are in my signature minus my tune. I will say I'm spiking at 24.5 psi upon spool up, then levels at 22/23 then begins to taper down to 20 by the time I get to redline. I'm not sure what tuning strategy and intake manifold pressures you are seeing.

I think thermal management is very crucial on these cars, especially if driven spiritedly. For non PP cars, I think an upgraded radiator is a worthwhile investment, which seems to be in alignment with your existing optimization and longevity strategy. I myself will be adding a cooler thermostat in the very near future, once I get over my initial spending spree.

I've been contemplating upgrading to a 170° thermostat myself, and hence, that's why I was discussing it with a vendor the other evening.

Most people, like TheLion, are stating to see temps between 180°-190° while driven aggressively and that's about the same for me with the stock thermostat. I'm curious if that difference is attributed to the upgraded PP radiator being larger and more efficient. I'd really like to see some results from a lower thermostat on a PP car, but I might have to be the guinea pig with my car.

I'm also curious as to what differences there would be between the 160° Evenflo Livernois unit and the 170° RatStat unit. I'd almost order both of them to test and see some real world results, but I almost believe a lower thermostat would be better suited to the non-PP cars.

Oh well, I might eventually pull the trigger and do some testing just to have some solid data for everyone. I'm going to be looking into it a bit more over the upcoming months.

So a few points:

The stock tstat is 178*.

If you saw CHT's of 210-215 stock, it makes sense that with a 160* aftermarket unit that is 18* cooler you see temps of 180-195.

The reason that you always see a temp spread of about 15* from the rated temp is because the rated temp is the temp that the tstat BEGINS to open. There are several cycles that occur prior to fully open.

There is very little to be had by dropping your tstat's activation temp 8* VS stock, UNLESS it is continually passing through coolant. This would obviously not a smart design to implement into a driver, because that means that pressures nor temps are ever being regulated correctly. Before madness ensues...if it were a positive the OE design would also share this instead of being a closed system.

If you go with a physically larger IC, there are several things that are considered along with it. No matter what someone says, if you install a deeper or more thick IC you are altering the airflow at the radiator (lowering its cooling capacity) If you have a taller and/or wider (left to right) IC you are also blocking at least part of the rad. If you have an overall larger IC you also need a larger rad to compensate for that overall blockage.

In a perfect world to defeat heatsoak on the EB you would upgrade the air intake, radiator, FMIC and then install a lower temp tstat. You are attacking heat from all 4 angles.

Anyone know any good places to get a PP radiator for cheap? New they cost about as much as the Mishimoto ($500), but the Mishi has welded on end tanks which will be more robust with age. I've had the plastic end tank units leak in the past (although that was on a GM car...)., but if the price is significantly lower of a PP radiator might be worth the small risk (my 07 focus never had any radiator leaks with the poly crimp on tanks).

Scratch that "72.5% More Cooling Capacity Over the Base Radiator
53% More Cooling Capacity Over the Performance Package Radiator"

If their claims are even 50% true, then it would still have better cooling capacity than a PP radiator and the price is the same (new PP radiators are running about 500 flat cheapest I can find...). I'll go Mishi then.

Livernois Motorsports said:

So a few points:

The stock tstat is 178*.

If you saw CHT's of 210-215 stock, it makes sense that with a 160* aftermarket unit that is 18* cooler you see temps of 180-195.

The reason that you always see a temp spread of about 15* from the rated temp is because the rated temp is the temp that the tstat BEGINS to open. There are several cycles that occur prior to fully open.

There is very little to be had by dropping your tstat's activation temp 8* VS stock, UNLESS it is continually passing through coolant. This would obviously not a smart design to implement into a driver, because that means that pressures nor temps are ever being regulated correctly. Before madness ensues...if it were a positive the OE design would also share this instead of being a closed system.

If you go with a physically larger IC, there are several things that are considered along with it. No matter what someone says, if you install a deeper or more thick IC you are altering the airflow at the radiator (lowering its cooling capacity) If you have a taller and/or wider (left to right) IC you are also blocking at least part of the rad. If you have an overall larger IC you also need a larger rad to compensate for that overall blockage.

In a perfect world to defeat heatsoak on the EB you would upgrade the air intake, radiator, FMIC and then install a lower temp tstat. You are attacking heat from all 4 angles.

Click to expand...

Well, from what your saying, I should be seeing temps of around 175~180, not 185~195. During normal driving it's pegged about about 172. It's no until I start cruising on the highway or heavy throttle that the temps creep up to high 180's / mid 190's.

Livernois Motorsports said:

So a few points:

The stock tstat is 178*.

If you saw CHT's of 210-215 stock, it makes sense that with a 160* aftermarket unit that is 18* cooler you see temps of 180-195.

The reason that you always see a temp spread of about 15* from the rated temp is because the rated temp is the temp that the tstat BEGINS to open. There are several cycles that occur prior to fully open.

There is very little to be had by dropping your tstat's activation temp 8* VS stock, UNLESS it is continually passing through coolant. This would obviously not a smart design to implement into a driver, because that means that pressures nor temps are ever being regulated correctly. Before madness ensues...if it were a positive the OE design would also share this instead of being a closed system.

If you go with a physically larger IC, there are several things that are considered along with it. No matter what someone says, if you install a deeper or more thick IC you are altering the airflow at the radiator (lowering its cooling capacity) If you have a taller and/or wider (left to right) IC you are also blocking at least part of the rad. If you have an overall larger IC you also need a larger rad to compensate for that overall blockage.

In a perfect world to defeat heatsoak on the EB you would upgrade the air intake, radiator, FMIC and then install a lower temp tstat. You are attacking heat from all 4 angles.

Click to expand...

in this platform the intercooler is below the radiator. a thicker/wider intercooler would be parallel with the bottom of the radiator. a if anything shouldnt a taller one obstuct flow? Not sure if there was a confusion on the platform but to me doesnt make sense since all of the thicker stock mount intercoolers are below it.

Where does one grab a 160* tstat from?

RADARB8 said:

Where does one grab a 160* tstat from?

Click to expand...

Here : http://www.livernoismotorsports.com/product/LPP2515-160

Terry

RADARB8 said:

Where does one grab a 160* tstat from?

Click to expand...

https://www.livernoismotorsports.com/product/LPP2515-160

TheLion said:

Well, from what your saying, I should be seeing temps of around 175~180, not 185~195. During normal driving it's pegged about about 172. It's no until I start cruising on the highway or heavy throttle that the temps creep up to high 180's / mid 190's.

Click to expand...

I see what you are saying, but it is over-thought. Here, just look at all of the deltas for each metric that you had. 210-215*CHT-the 18* cooler 160* tstat=192*197. That should be you peak temp range under the same hard driving condition. Your closed shutters will bump your average of ~185-188 or so up a bit, so again that 192-197 is still in line.

Based upon all of the hard driving metrics the 160* tstat and tuning is performing slightly better than the mathematics say it should be. Not by much, but it is better.