patsmx5

iTrader: (16)

I don't agree with the first part. From what I understand, thermostat's are Designed to open and close at certain temperatures. Example, start open at 180, fully open by 192. Just an example. If I'm wrong please explain/show me!

I'm not spending my time/money TESTING THINGS AND THEN REPORTING WHAT WORKS AND WHAT DOESN'T WORK to be different.

I want my car to go fast, and be reliable, and right now I think I can improve the cooling system so I am TESTING multiple things to see what WORKS and what DOESN'T. So at the end of the day if nothing works how I want, I'll do something different. So far, nothing has worked how I want, I have shared that for other people to learn from and asked for suggestions on new things to try. Now I'm TESTING something else!

If you really think I'm spending this much time and effort for any other reason you are mistaken. So far the only suggestions have been to just put it back to stock (give up testing, that's the consensus) or install a valve and switch between mixing manifold and radiator hose (i've done this before, it does work, but packaging that would be almost impossible now with the big SC). I was hoping I can find a simpler solution like just putting a restrictor in the hose, going to do this now actually, will post back how the smaller one does in a bit.

deezums

iTrader: (3)

I have a 195 degree thermostat in my car, when in low load it runs from 180-195. Explain that?

The pellet is wax and has hysterics. You know what a large opening does in low load driving, how do you expect a thermostat with a larger opening area to work in a stock cooling system? Does a stock car have wild fluctuations in temperature?

The hysterics go out the window under load, the thermostat goes full tilt. An identical car with the same setup as yours with a proper heater core will cool exactly the same. I-freaking-dentical.

The difference is the other car will hold a steady uniform temperature under light load and will be possible to tune as a daily driver.

Normal people get this and know you can not used a fixed size orifice to control the temperature in a motor, but keep doing the same thing over and over again...

Joe Perez

iTrader: (8)

If you are absolutely convinced that the presence of the mixing manifold is unacceptable, and yet want your engine to reach normal operating temperature in street driving, place a bypass style thermostat (such as from a BMW 2002) on the outlet of the heater core, with the "cold" port connected to the lower radiator hose, and the "hot" port connected to the upper hose.

You're not going to beat that design for cooling performance vs. streetability.

curly

iTrader: (25)

Dude, I know post counts aren't everything, but 124,194 posts worth of experience in this thread are telling you to route the heater core return towards the god damn mixing manifold.

Stop trying to be creative and innovative to solve a problem that doesn't exist. Route the damn heater return to the lower radiator hose.

patsmx5

iTrader: (16)

Update.

Tried a 3/16" restrictor, that didn't work. Better, but still seeing around 170*F temps at cruise.

Then tried a 7/64ths. Perfect! Once up to temp, I reset my gauge min/max and drove it. Idle, low speed, highway, A/C on or off, WOT pulls to redline, you name it, temps stayed between 177 min and 181*F max. Every time I looked at the gauge it was 179-181, but apparently it registered a 177 at least once.

Anyways, that problem (overcooling) is solved now. And now I have no hot water going back to the water pump to boot. I now have a better cooling than if I left a 5/8" heater hose constantly sending water back to my mixing manifold.

Tomorrow when my 195*F gets here I'm going to swap it in since that's probably better for the engine anyways, and it seems the stock ECU wants that temp to do the emissions test.

That's a lot of hate from you guys considering this actually worked and I have thus improved the cooling capacity of the car!

patsmx5

iTrader: (16)

Yes that would work very well, but it would be challenging to package that valve anywhere near where it should go because I have a big SC in the way. But I do thank you for your post, as you're right, that would work best as you say. Luckily I seem to have found a restrictor size that's working for me now.

patsmx5

iTrader: (16)

See my last post, but I got it working now. As for your temp fluctuations, my guess is a bad or sticking thermostat. If you have a 195*F thermostat it shouldn't be down at 180 after it's warmed up.

patsmx5

iTrader: (16)

I will not stop being creative and innovative, that's a promise. I enjoy designing and building things. To me 1/2 the fun is building the car.

Regarding the "a problem that doesn't exist" part, that's your opinion. I want the best cooling I can get, and this will help, anyone who understands basic heat transfer can confirm that what I have done will positively improve cooling.

Just like all the other little things I've done to improve my cooling, every bit helps. Same for the engine, 50 little things all come together to make the system awesome.

Dunning Kruger Affect

I can't wait for the thread in 3 months: "guys my car overheated at the track! I don't know why!" Or better yet, when it's the middle of summer and your **** boils over.

patsmx5

iTrader: (16)

I hope I'm on the track in 3 months! And yes, if it overheats I'll change something. And I'll have a reasonable idea as to why, seeing how i have a total of 12 temperature sensors under the hood and can directly measure heat exchanger effectiveness for the radiator, intercooler and oil cooler. Since I don't know what I'm doing and all.

aidandj

iTrader: (5)

Doesn't the restrictor make your heater ****?

patsmx5

iTrader: (16)

I sure thought it would. It does not though. I haven't measured vent temps, and I will and will post that data when I do.

I tested it at idle, with air on outside, and fan on high (worst case as pump speed low, so less water flow). My estimate is the vent temp air was around 130*F. It's plenty hot, but not stifling. My 05 subaru will cook you on high, this car won't, but it's plenty of heat. I kept trying larger restrictors at first since I thought there's no way the heater would work with a tiny one. I would guess it's like putting the heat on 80% of the way instead of 100%, but again, when I find my gauge I'll measure temps and post the data.

deezums

iTrader: (3)

Less than a day of testing and you are ready to call it fixed. Wait till it gets 20 degrees colder then let me know how well it gets to temp.

If your setup is so much better, it must get to temperature faster right? Care to post a log, since you have so many sensors?

I'm out, it's clear you have no idea what you are doing and don't seem to care. Have fun creating problems to fix issues that don't exist.

patsmx5

iTrader: (16)

Been testing for 3 days, wasn't posting the entire time, there's more info in my build thread, link in my signature if you care to see it.

I'm here to tell you I'm not perfect, and you may very well be right that when it gets colder it starts overcooling. I don't know that right now. Tonight it was 67 and raining. But if it's 30*F it may very well overcool, won't know till that happens.

I will post logs when I get the MS3 and 24CH input/output boxes all wired up and working. For now I've posted what I have which is all OBD II data since it's running on stock ecu right now. Good news is I got no codes/ all monitors to "ready" so should get it inspected Monday and then that crap's gone and back to MS3 goodness!

I'm sorry you don't think I know what I'm doing. I screw **** up all the time, and make mistakes, so what? You can laugh and insult me, but I'm at least being honest and sharing my experience/data (whether good or bad) for everyone to see. I've always done this. Apparently some people would rather laugh and throw insults than discuss how to make these cars better. That's not why I come here. End of the day I learn more and my car gets better so I guess it's worth it!

Savington

iTrader: (31)

You aren't making the car better. You broke it by bypassing the thermostat, but you seem to be unable to grasp that fact. Your restrictor just lessens the effect of your thermostat bypass. The car will still take significantly longer to come up to operating temp and still won't come up to operating temp in colder weather.

sixshooter

iTrader: (12)

I agree.

And he removed the factory designed constant movement of coolant at a stable, even temperature across the engine. That movement is designed to reduce hot and cold spots within the engine under light and medium load. Unevenness is bad (which is why warm and cooler coolant is mixed in a strange device known as a "mixing manifold"). Temperatures below optimal contribute to significant wear and don't allow certain harmful elements to be efficiently removed from the oil (moisture and fuel among them).

And now to repair the self-induced problem he restricts the flow further, thereby creating a greater incidence of hot spots and temperature differential. And it reduces the volume of flow across the thermostat, giving it a skewed view of the state of the engine.

patsmx5

iTrader: (16)

Thanks for the mostly constructive feedback.

I know there is water bypassing the thermostat, I did it myself. The whole point was to only bypass a tiny amount, just enough for the heater to work, thus a hole smaller than 1/8". As you said the restrictor lessens it but it's still happening on a now very small scale. It will take longer to come up to temp as you say, and I have not tested whether it will overcool at cold weather. You may very well be right on this, I won't know till it gets in the 30's. If it in fact does, I will have to change something for sure. I don't think it will as it had no problems yesterday in the high 60's and rain too but again not tested in cold yet.


Also constructive feedback, thank you.

You are right that now there is hardly any cooling circulating through the engine under light and medium loads now vs a stock configuration. And you're right that it's worse regarding this than using the mixing manifold, I agree.

I guess my question is, does that matter? The flow will be the least at light loads, which is when heat loading is the least, so I don't know if that will really be a problem. Under hard load, thermostat will be open and there should be plenty of flow through the motor then. How would I know if this is actually a problem or not? Maybe through tuning spark at low and medium loads?

I guess the question at this point is, which is better, more even coolant temps at lighter loads, or more cooling capacity at higher loads? Best of both worlds would be what Joe said a thermostat that can switch between mixing manifold and radiator. I would just be a super pain to put that valve anywhere on my setup.

Edit: Also I see I'm getting a lot of negative props for testing something and reporting what's working and what's not working. Seem lame people would neg prop somebody for sharing their data, whether it's good or bad, works or doesn't, at least I'm posting it for people to see.

Savington

iTrader: (31)

You don't need to test whether or not it comes up to temp in colder weather. It absolutely will not. Your current solution restricts overall system flow so that the current temperature differential across the radiator is adequate to cool the amount of water that is being circulated. As the temp differential increases, the water will overcool.

What you've also done is restricted heater core flow, and by doing that, you've inhibited heater core function. Again, another thing that doesn't really need testing done. The temperature of the water inside the heater core hasn't changed, but the flow rate has decreased dramatically, so when you turn the heater on, you're pulling the same amount of heat out of a smaller volume of water. The heater will probably blow warm for a short period of time, but if you leave it on, it will eventually go cold since there's not enough warm water circulating through the core to provide an adequate amount of heat energy to the core.

There's a simple solution to both of these problems (bypassed thermostat causing overcooling in cold weather + limited heater core function as a result of limited heater core flow): Put your mixing manifold back in

Joe Perez

iTrader: (8)

patsmx5

iTrader: (16)

You nor I know this. It will have to be tested. I know for sure that I'm bypassing some water, and it's not enough to stop the engine from reaching thermostat temp. It could be on the edge now, or not. Will have to test with colder weather to know for sure. Just to makeup numbers to explain this, lets say the engine's making 10 units of heat at light load and my bypass is letting 7 units of heat out. So in this case, 7 goes through the bypass, 3 goes through thermostat, so there's still 3 units of headroom before the thermostat can't do it's job. Just an example to explain what it happening. No doubt that if it kept getting colder and colder, at some point, the bypass would let it overcool. But whether that's 10*F cooler of 80*F cooler you nor I know that.



Already tested this, heater still works, I left it on for 30 minutes at idle as explained above (fan high, pulling outside air). It never went cold, vent temps were around 130*F but I'll measure them to verify, maybe tonight we'll see.

True, but then I sacrifice cooling capacity by letting some hot water bypass the radiator. I think everyone in this thread understands the compromises of both setups at this point. I'm taking a compromise as you say in your two points for added cooling capacity. End of the day I searched, couldn't find anyone who's tested this, so I am. If it proves to suck, I'll change it. If it helps, I'll keep it.