[Welding Rod]

Re: ACT ECT MPH

OK, I tried this again. I got an American made Stant 180 degree thermo, part number 13978. I tested again at the same place and duplicated the run as close as I could. Only difference was today read 78 on the bank's thermometer a couple miles away from my test site, everythings else, gas, boost pressure, test hill, etc. were the same.

At an easy cruise on flat ground around town and on the hiway up to 65-70 MPH it was running 206-210, that is up to approximately 20 degrees less than with the OEM 198 thermostat. So far so good.

Then back to the hill:

MPH / ECT / ACT
43 / 224 / 78 (I held steady here at 43 MPH again prior to going WOT - this is on a grade hence the 224 ECT instead of the lower flat cruise numbers mentioned above)
44 / 226 / 78 (WOT from here on)
51 / 226 / 78
60 / 226 / 77
65 / 226 / 75
72 / 228 / 75
76 / 228 / 75
78 / 230 / 77
81 / 230 / 77
83 / 233 / 78
87 / 233 / 78
90 / 233 / 78
94 / 233 / 80
96 / 233 / 80

Looks like with a thermostat that is 18 degrees colder, I am running 2 degrees colder at WOT during test conditions that are about 10 degrees warmer. Not what I had hoped for.

With the 198, I stabilized at 230 before I started, and then rose up to 235, gaining 5 degrees. With the 180, I stabilized at 224 and peaked at 233, gaining 9 degrees.

Looks like there isn't a bunch of reserve left in the cooling system at this power level.

Below are the second and third tests I did today. I put the 180F thermostat back (like the test above from a year ago) and tried it again.

87F Ambient on these test, 78F on the old one above:

ECT / MPH / ACT

Run #1
215 / 53 / 84
217 / 56 / 84
219 / 58 / 86
221 / 59 / 87
222 / 62 / 87
222 / 66 / 84
222 / 71 / 82
224 / 73 / 80
224 / 74 / 78
224 / 78 / 80
224 / 81 / 80
224 / 85 / 80
226 / 89 / 82
228 / 92 / 82
228 / 90 / 82

ECT / MPH / ACT

Run #2
217 / 53 / 87
219 / 53 / 87
221 / 54 / 87
221 / 55 / 87
222 / 56 / 87
222 / 57 / 87
222 / 59 / 87
222 / 63 / 84
224 / 67 / 82
224 / 71 / 80
224 / 76 / 80
224 / 78 / 80
226 / 81 / 80
226 / 85 / 82
226 / 89 / 82
228 / 81 / 82

Quite an inprovement... at 242F with the OEM thermostat the ECU pulls about 6 degrees (over 8 degrees at lower RPM, say 3K), while in this test at 228F it is only about 1 degree.... yes you can feel the difference in the extra 5 degrees advance.

I don't even want to know what the ECT would have been with the OEM thermstat and OEM radiator... plus a richer anti-freeze mix and no water wetter

Compared to the same 180F thermostat with the OEM radiator, ECT dropped 5F when tested at an ambient temperature 9F higher...

Not too bad, but still not as good as I had hoped. Next step will be to build a splitter / duct to keep air from spilling below the IC and radiator. Right now I have nothing between the bottoms of the IC and radiator.

 

[focusownerskid]

Re: ACT ECT MPH

Wow, I expected it to be much more effective

I realize the tests were slightly different variables, but, all the same, what could be done to make it any better?

Bela, how are you keeping it under 200?

- Drew

 

[Welding Rod]

Re: ACT ECT MPH

Well I should also note that the low speed fan turns off at the factory setting of 53 MPH, and the high speed fan isn;t set to come on during high load until 226F... so for operating almost without fans, I don't think it is too bad.

Before, the 226 setting was OK since the ECT exceded that by a fair margin anyway, but now that is pretty much my max ECT.

So I think if I drop the "high speed fan on" down a little bit I should be looking pretty good.

I didn't want to change a bunch of stuff before doing those tests though. I may have time to try that this afternoon.

 

[Penguini66]

Re: ACT ECT MPH

Nice work Rod! You are officially the [FJ] king of testing and data. Actually, you're my complete opposite.

Bri asked me last weekend at Summit Point if I wanted him to datalog my car while on track. I told him I'd prefer not to know. Especially since I sit in the staging lines with the AC on max. So far 17 on track hours and 60k post-turbo street miles logged. I figure there's not much I can do now.

Not radiator talk but one thing I did notice is how close your ACT/IAT readings are to the "bank's thermometer" at the beginning of each test:

Test 1 - Ambient/bank = 68 ACT= 66
Test 2 - Ambient/bank = 78 ACT= 78
Test 3 - Ambient/bank = 90 ACT= 89

I think it tells us two things: 1) The air filter is getting clean cool air. 2) The intercooler and/or water methanol injection(or whatever you're using now) is definately doing its job.

I never understood the reasoning in using a lower temp thermostat. It seems to me that, under long hard engine abuse, an open thermostat is an open thermostat. Whether it opens at 180 or 198 doesn't matter because you're way above those temps anyway and the thermostat is theoretically never going to close. I guess what I'm getting at is that in your tests, wouldn't the thermostat be open the entire time?

What I would be interested to see is how the ECT temps compare(with different temp thermostats) at a 3k rpm cruise down the highway. It would also be interesting to see the difference with the car just sitting at idle.

The big advantage of a cooler thermostat would be that it theoretically could/should be able to keep the ECT lower in preperation for a "burst of speed". Say, at a drag race. You're sitting in the staging lines with the A/C on because its hot outside. With a cooler thermostat you might be able to get the initial temp down a few degrees.

But then again, I could be completely wrong. For now, I'll use the excuse that its Monday morning and I've only had one cup of coffee.

 

[Welding Rod]

Re: ACT ECT MPH

Not radiator talk but one thing I did notice is how close your ACT/IAT readings are to the "bank's thermometer" at the beginning of each test:

Test 1 - Ambient/bank = 68 ACT= 66
Test 2 - Ambient/bank = 78 ACT= 78
Test 3 - Ambient/bank = 90 ACT= 89

I think it tells us two things: 1) The air filter is getting clean cool air. 2) The intercooler and/or water methanol injection(or whatever you're using now) is definately doing its job.

Yes my intake is in a great place, the entire front of the IC gets unobstructed airflow, and you can see the temps drop when the water injection comes on.

I never understood the reasoning in using a lower temp thermostat. It seems to me that, under long hard engine abuse, an open thermostat is an open thermostat. Whether it opens at 180 or 198 doesn't matter because you're way above those temps anyway and the thermostat is theoretically never going to close. I guess what I'm getting at is that in your tests, wouldn't the thermostat be open the entire time?

Exactly what I thought. And also what the tests a year ago would lead you to believe. That is why I put the OEM back in yesterday and tested it.... to prove the point that any benefit would be very minor... glad I didn't make any predictions on the outcome.

As you can see in yesterdays tests, that is clearly not the case once ambient temps are high... go figure. You just can't beat instrumented testing.

What I would be interested to see is how the ECT temps compare(with different temp thermostats) at a 3k rpm cruise down the highway. It would also be interesting to see the difference with the car just sitting at idle.

I didn't check at idle, but cruising down the highway yesterday at about 60-65 MPH, at 90F ambient with the OEM 198F thermostat I got up to about 232-233F. With the 180 thermostat at 87F ambient it was considerably lower.... I didn't write in down, but somewhere in the 210-220 range.... you can see in my data log that at the beginning of the runs it was about 215-217F, and that was going up a pretty good grade.

 

[belacyrf]

Re: ACT ECT MPH

Rod, dont you have a relocated IAT??? So the low temps is a testament to your intercooler right?

As for the thermometer... basically the spring tension changes at certain temps does it not? So a 180 degree thermometer, doesn't just "open" earlier, it opens "more" as temps rise correct?

 

[Welding Rod]

Re: ACT ECT MPH

OK, I tried this again. I got an American made Stant 180 degree thermo, part number 13978. I tested again at the same place and duplicated the run as close as I could. Only difference was today read 78 on the bank's thermometer a couple miles away from my test site, everythings else, gas, boost pressure, test hill, etc. were the same.

At an easy cruise on flat ground around town and on the hiway up to 65-70 MPH it was running 206-210, that is up to approximately 20 degrees less than with the OEM 198 thermostat. So far so good.

Then back to the hill:

MPH / ECT / ACT
43 / 224 / 78 (I held steady here at 43 MPH again prior to going WOT - this is on a grade hence the 224 ECT instead of the lower flat cruise numbers mentioned above)
44 / 226 / 78 (WOT from here on)
51 / 226 / 78
60 / 226 / 77
65 / 226 / 75
72 / 228 / 75
76 / 228 / 75
78 / 230 / 77
81 / 230 / 77
83 / 233 / 78
87 / 233 / 78
90 / 233 / 78
94 / 233 / 80
96 / 233 / 80

Looks like with a thermostat that is 18 degrees colder, I am running 2 degrees colder at WOT during test conditions that are about 10 degrees warmer. Not what I had hoped for.

With the 198, I stabilized at 230 before I started, and then rose up to 235, gaining 5 degrees. With the 180, I stabilized at 224 and peaked at 233, gaining 9 degrees.

Looks like there isn't a bunch of reserve left in the cooling system at this power level.

'nother test. Basicly the same as above, same thermostat, etc, but with the Fluidyne radiator and now with the fans set to turn on at 222 - during all previous tests the high speed fan was set to 232.

BTW In a previous post above I was mistaken about using a 226F fan activation - that was "hi-load with low vehicle speed" activation, not strictly ECT based.


This was at 82F ambient, the test above was at 78F ambient.

MPH / ECT / ACT

53 / 215 / 84
55 / 217 / 82
57 / 217 / 82
61 / 219 / 78
65 / 219 / 75
69 / 219 / 75
73 / 219 / 75
78 / 219 / 77
82 / 219 / 77
86 / 221 / 77
88 / 221 / 78
91 / 222 / 78
89 / 224 / 77

"Problem" here was at 82F ambient the ECT didn't get hot enough to activate the fan until the test was over. I will need to repeat this on a hotter day so I compare the results with the high speed fan lowered, with the last test I did at 87F ambient and the fan set at 232F.

Not too bad though. At 88 MPH it is 12 degrees cooler, even though ambient was 4 degrees higher and the fan had not yet activated.

The extra timing feels good. The difference between 220 and 235 ECT is about 3 degrees, between 220 and 242 about 5.5 degees. It is more like driving the car on a cool morning.

Bela - Yes my ACT sensor is relocated.

 

[Welding Rod]

Re: ACT ECT MPH

OK, I tried this again. I got an American made Stant 180 degree thermo, part number 13978. I tested again at the same place and duplicated the run as close as I could. Only difference was today read 78 on the bank's thermometer a couple miles away from my test site, everythings else, gas, boost pressure, test hill, etc. were the same.

At an easy cruise on flat ground around town and on the hiway up to 65-70 MPH it was running 206-210, that is up to approximately 20 degrees less than with the OEM 198 thermostat. So far so good.

Then back to the hill:

MPH / ECT / ACT
43 / 224 / 78 (I held steady here at 43 MPH again prior to going WOT - this is on a grade hence the 224 ECT instead of the lower flat cruise numbers mentioned above)
44 / 226 / 78 (WOT from here on)
51 / 226 / 78
60 / 226 / 77
65 / 226 / 75
72 / 228 / 75
76 / 228 / 75
78 / 230 / 77
81 / 230 / 77
83 / 233 / 78
87 / 233 / 78
90 / 233 / 78
94 / 233 / 80
96 / 233 / 80

Looks like with a thermostat that is 18 degrees colder, I am running 2 degrees colder at WOT during test conditions that are about 10 degrees warmer. Not what I had hoped for.

With the 198, I stabilized at 230 before I started, and then rose up to 235, gaining 5 degrees. With the 180, I stabilized at 224 and peaked at 233, gaining 9 degrees.

Looks like there isn't a bunch of reserve left in the cooling system at this power level.

'nother test. Basicly the same as above, same thermostat, etc, but with the Fluidyne radiator and now with the fans set to turn on at 222 - during all previous tests the high speed fan was set to 232.

BTW In a previous post above I was mistaken about using a 226F fan activation - that was "hi-load with low vehicle speed" activation, not strictly ECT based.


This was at 82F ambient, the test above was at 78F ambient.

MPH / ECT / ACT

53 / 215 / 84
55 / 217 / 82
57 / 217 / 82
61 / 219 / 78
65 / 219 / 75
69 / 219 / 75
73 / 219 / 75
78 / 219 / 77
82 / 219 / 77
86 / 221 / 77
88 / 221 / 78
91 / 222 / 78
89 / 224 / 77

"Problem" here was at 82F ambient the ECT didn't get hot enough to activate the fan until the test was over. I will need to repeat this on a hotter day so I compare the results with the high speed fan lowered, with the last test I did at 87F ambient and the fan set at 232F.

Not too bad though. At 88 MPH it is 12 degrees cooler, even though ambient was 4 degrees higher and the fan had not yet activated.

The extra timing feels good. The difference between 220 and 235 ECT is about 3 degrees, between 220 and 242 about 5.5 degees. It is more like driving the car on a cool morning.

Bela - Yes my ACT sensor is relocated.

Nice and warm out today and the electricity went out at work, so time for another test...

Same everything as above, except ambient temp is 91F, and I now have a 3" turbo back exhaust added which appears to be increasing load by approximately 5-10%.

MPH / ECT / ACT
53 / 221 / 93
55 / 221 / 93
56 / 221 / 93
58 / 221 / 93
59 / 222 / 93
60 / 222 / 93
62 / 222 / 91
65 / 222 / 87
70 / 224 / 84
73 / 224 / 82
77 / 224 / 82
81 / 224 / 82
84 / 224 / 82
89 / 224 / 82
91 / 226 / 84
93 / 226 / 84

Off Gas

86 / 228 / 84
68 / 226 / 86
62 / 224 / 87
57 / 222 / 86
55 / 221 / 86
53 / 219 / 84
52 / 217 / 84

So WFO in 4th gear up a very steep grade on a dry 91F day I am now getting less than 1 degree retard from ECT.

No indications on the Safeguard either.

The high speed fan should have come on at 59 MPH, so I don't think lowering it further would be of any benefit. However I think there is still considerable room to improve natural airflow by adding ducting between the rad and IC.

 

[lourenco]

You have a 180F tstat right? What would happen if the high speed fans turned on at 200f? Would it stay around 200F? I still need to hook up pectel to control the fans or flash the ecu to turn the fans on sooner. I have a 170 tstat that I still need to install.

My tempatures stay around 217F under boost at night with 80F tempature out side. During a hot day it will go little higher.

I have see as high as 230F on a hot day.

 

[Welding Rod]

Yes I use a 180.

I don't think further lowering the high speed fan on point would have any effect, other that simply slowing the time to reach final temperature a bit... although it could keep the car operating sinificantly cooler during short spurts of boost as temp creeps up. The fans would run all the time though.

But I am not looking to get the temp any lower than it needs to be to prevent timing from being pulled. My goal has been to keep peak temp from exceeding 225F, which I have just about reached, even on a 91F day WFO uphill. I am pretty confident that after I add the "wind tray" between the rad and IC that it will easily meet or beat the goal.

 

[OJEngineeringSr]

Yes I use a 180.

I don't think further lowering the high speed fan on point would have any effect, other that simply slowing the time to reach final temperature a bit... although it could keep the car operating sinificantly cooler during short spurts of boost as temp creeps up. The fans would run all the time though.

But I am not looking to get the temp any lower than it needs to be to prevent timing from being pulled. My goal has been to keep peak temp from exceeding 225F, which I have just about reached, even on a 91F day WFO uphill. I am pretty confident that after I add the "wind tray" between the rad and IC that it will easily meet or beat the goal.

Rod,

You are right on target. In my years racing the H and A brands I've never seen the high operating temps from the cooling system that the Focus runs at. I think part of that is emission controls. The faster and the hotter the engine runs the leaner and cleaner it will run in the emissions lab. But I'm always surprized at the amount of work and money people spend on everything except the cooling system. I want to personally thank you for doing all this work. It really shows where one of the biggest weak links are in the Focus.

 

[belacyrf]

Rod... just FYI... I have my fans (manually) set to come on about 190-200 (somewhere in there, its not exact). But my ECT's never go over 200 in short spurts. I haven't logged anything recently (100 degree days). I'll do that soon and post the results.

 

[Welding Rod]

Thanks Oscar, I appreciate that.

I wanted to bring up an older thread where Slick Shoes had posted some data logging of ZX3s and SVTs.

GOOD SHORT THREAD

I understand that the SVT gets its readings from the actual coolant, while the regular ZETEC is in fact reading head temp as "ECT". I have no first hand knowledge of either. If this is the case, I am not sure how my ECU provided ECT readings correlate to actual coolant temp.... the true coolant temp may in fact be considerably cooler.

In any case I have been operating under the simple assumption that a temp great enough to pull timing is undesireable. Typical "ECT" readings as seen by the ECU in a standard ZETEC under heavy load definitely reach a range that results in significant spark retard.

The Non-SVT that is datalogged in Slick's post there has high enough ECT for some crazy retard.

Bela - Under max load and say 4.5K RPM, how hot does ECT need to be in the SVT before you reach 1 degree of retard? 5 degrees retard?

Slick - What was the ambient temp that day?

 

[Welding Rod]

Bela - Under max load and say 4.5K RPM, how hot does ECT need to be in the SVT before you reach 1 degree of retard? 5 degrees retard?

Slick - What was the ambient temp that day?

Bumping in case Bela and/or Slick didn't see this.

.... or if anyone else can answer the SVT timing retard question .... ?

 

[Pak]

Bumping again, this is useful information.

 

[Tony D]

I have both Fluidyne radiators and 180 degree t-stats in stock if you need them.

Tony D

 

[CatMostFeared]

Really nice data logging thanks.

 

[Tobyboom]

Back from the dead...

 

[Honda Hunter]

+1

 

[CatMostFeared]

This is is really good info it should be a sticky