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2005 Lotus Elise
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I'm still waiting as well.... Just wondering if you've received yours yet or not. I'm looking forward to any more results you may get!
I haven’t checked recently.

Interestingly the 198F Mocal thermostat I got from the UK for my stock plate also had the pin loose, but the 176F one wasn’t loose. I tested the 198F one first and it is also acting like it is partially stuck open and not reaching its target temp. I’m planning to post that data with the 176F Mocal thermostat data after I swap it at my next oil change.
 

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I took data with the stock oil cooler with the default thermostat, a 198F (92C) thermostat, and a 176F (80C) thermostat. I was curious to see how the stock plate compares to the Mishimoto plate, with a higher temp thermostat, since the stock thermostat regulates to a lower temp. If you ask a Lotus parts person, our stock Mocal plate does not offer a replacement thermostat - you have to buy a whole new sandwich plate. I found a UK site that offered Mocal wax thermostats, that looked like the right size, so I ordered a couple (80C and 92C). The 92C one came with the pin loose, same as the three different Mishimoto 198F thermostats I got from Amazon. The data below shows that the loose pin didn't regulate to its setpoint - it was significantly lower than the one with a lower setpoint. Seems like a lot of bad batches of 90-ish C wax thermostats...
)

I plotted the data below, and also included a version with the three temperatures directly, instead of delta between coolant and plate/pan.

Rectangle Slope Font Parallel Plot

Rectangle Slope Line Font Parallel


Below are the full plots for the OE plate with default, OE plate with 198F, and OE plate with 176F thermostats.
Slope Rectangle Plot Font Parallel
Rectangle Azure Slope Plot Font

With the 198F thermostat I had a little fun seeing the temp rise when running at higher rpms (12-17 mins at ~4400rpm and 17-22 mins at 5000rpm). Not surprising that the higher RPMs definitely increases the oil temp.

Product Rectangle Slope Azure Plot

My conclusion: I don't see any meaningful improvement between the Mishimoto and the OE plate with the 176F thermostat. Given, those two datasets aren't at the same ambient temp, but the plate temp lags the coolant temp by about the same amount, and they both reach operating temp in about 10 mins.

This was all with the BOE oil pan without insulation (since I previously found that the pan insulation didn't affect the temp measured in the sandwich plate with the Mishimoto plate, discussed in post #750).
 

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Discussion Starter · #766 ·
It is still the pan
Your results mimic the results of others with the larger pan
The larger pan overwhelms the oil coolers as the source of delay in oil warming.
This is consistent with others experience with the larger pan
 

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It is still the pan
Your results mimic the results of others with the larger pan
The larger pan overwhelms the oil coolers as the source of delay in oil warming.
This is consistent with others experience with the larger pan
I can heavily insulate the pan again, which would then almost certainly have less heat loss than an uninsulated stock pan. Or would you only consider the results meaningful with the stock pan?
 

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Discussion Starter · #768 · (Edited)
it is both the oil volume and thermal capacity of the pan that affect the warming time
Think about it. If your numbers are accurate, it means the oil coolers don't matter. That doesn't make sense.
Or it means the Mishimoto plate is not working the same as the mishimoto plate I have, which shows markedly less bleeding of oil than the factory plate, as evidenced by the temperature measurements I made at the oil coolers in my initial testing

I think to be apples to apples, as I have said before, you need to do an idle test.
You also need to measure the temps of the oil coolers.



I keep saying, do not put a big pan on a street car.

You have posted a lot of data, but the labels are sometimes unclear. coolant?
Also, my oil temps are always above 180 degrees, always once it comes up. If I get on it, 205 is common, measured at the plate.
So as with all the data we have seen, your oil temps with the larger pan remain lower
 

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As we have learned from many people here, the pan overwhelms the effect of the coolers.

Went away from this thread for a while and then just caught back up. I had a dumb question.....But since most are in agreement that the large alum pan dissipates too much heat, why not work with it rather than fight it?

Just a crazy thought but wondering if it might be possible to eliminate ALL the oil coolers (save the weight of the front mounts or simplify not needing the rears) and see what temps are.

If needed, one could easily weld on almum fins to effectively make a heat sink and position NACA to blow across pan. It could be quite large in surface area and extend around pan. If you did not want to weld it, you could machine a heat sink and then screw mount it to the studs of the pan and use a thermal conductive paste to make the heat transfer.

Just the thought popped in my head of if the alum pan makes that big a difference, perhaps we dont even need coolers? I have seen this design in several helicopters where they are designed to be cooled by air instead of external coolers. We have a great air source under the car w/ a NACA directing flow. I also verified there is room for it under the belly pan.


I know it might sound silly but I tend to think the simplest solution is often the best. Coming from an aviation background, just seems like so much complexity is going into this. With the alum pan seemingly demonstrating such a dramatic effect, why not just give it a helping hand and see if it is sufficient?
 

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Discussion Starter · #770 ·
Went away from this thread for a while and then just caught back up. I had a dumb question.....But since most are in agreement that the large alum pan dissipates too much heat, why not work with it rather than fight it?

Just a crazy thought but wondering if it might be possible to eliminate ALL the oil coolers (save the weight of the front mounts or simplify not needing the rears) and see what temps are.

If needed, one could easily weld on almum fins to effectively make a heat sink and position NACA to blow across pan. It could be quite large in surface area and extend around pan. If you did not want to weld it, you could machine a heat sink and then screw mount it to the studs of the pan and use a thermal conductive paste to make the heat transfer.

Just the thought popped in my head of if the alum pan makes that big a difference, perhaps we dont even need coolers? I have seen this design in several helicopters where they are designed to be cooled by air instead of external coolers. We have a great air source under the car w/ a NACA directing flow. I also verified there is room for it under the belly pan.


I know it might sound silly but I tend to think the simplest solution is often the best. Coming from an aviation background, just seems like so much complexity is going into this. With the alum pan seemingly demonstrating such a dramatic effect, why not just give it a helping hand and see if it is sufficient?
The baffling and larger capacity are useful on the track, but there is no way to speed up oil warming when you have added so much volume to the oil.
THE definition of a BTU: energy it takes to warm up one pint of water one degree.
Think on that.
Add 30 percent more oil and what is that going to do to the warm up time of the oil given the same BTU input?
And ICE creates heat with a little rotational energy on the side. So two identical cars one with twice as much oil in the pan, I think we can safely say what is going to happen to the time it takes the oil to come to temp.
It will double.
It is my contention that the number of BTUs required by the increase in the oil volume dwarfs the amount of BTUs dissipated by a lossy thermostat compared to a better thermostat

At the end of the day, if you are not regularly tracking your car on high speed tracks, probably on slicks, [probably there are guys here who can tell you exactly which turns on which tracks are the problem] if you are just street driving with an occasional track day where you are not at the limit at high speed, the larger oil pan is a net negative.
 

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2005 Ardent Red Elise, Touring Pack
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Just ordered a pair of replacement thermostats from Mishimoto, one at 200F and the other at 185F. If the 200F one arrives with the pin still in I'll try it out. If not, the 185F one is going in. I measure oil temperature at the plate via an electronic gauge. Street car, stock oil pan, stock NA tune, dual oil coolers.
Anyone know if you can easily swap the thermostat without doing a full oil change or without getting oil everywhere?
 

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Less is Better
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Just ordered a pair of replacement thermostats from Mishimoto, one at 200F and the other at 185F. If the 200F one arrives with the pin still in I'll try it out. If not, the 185F one is going in. I measure oil temperature at the plate via an electronic gauge. Street car, stock oil pan, stock NA tune, dual oil coolers.
Anyone know if you can easily swap the thermostat without doing a full oil change or without getting oil everywhere?
Yes, minimal oil comes out. I even had to remove the plate to get room to free the thermostat and there was no need to even top off the oil.
 

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Yes, minimal oil comes out. I even had to remove the plate to get room to free the thermostat and there was no need to even top off the oil.
Interesting, I hadn’t thought to try swapping the thermostat without draining the oil and pulling the oil filter.


Just ordered a pair of replacement thermostats from Mishimoto, one at 200F and the other at 185F. If the 200F one arrives with the pin still in I'll try it out. If not, the 185F one is going in.
Make sure the pin isn’t loose either. On some I’ve been able to push the pin in a little with my finger, and those never reached their set point in easy driving.
 

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Interesting, I hadn’t thought to try swapping the thermostat without draining the oil and pulling the oil filter.



Make sure the pin isn’t loose either. On some I’ve been able to push the pin in a little with my finger, and those never reached their set point in easy driving.
Dang, I'll watch for that too. Thanks
 

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The baffling and larger capacity are useful on the track, but there is no way to speed up oil warming when you have added so much volume to the oil.
The difference in oil volume for me is only 1 qt. From 4.7 qt to 5.7 qt w/ filter, with the BOE pan. Same heat capacity as ~1.9 kg of aluminum.

In normal driving, the oil in my car reaches steady state temp about 5 mins after the coolant reaches steady state, with conditions that would make the warmup time worse not better: slightly higher oil volume, slightly higher heat loss due to larger surface area of aluminum pan, cool ambient temperature. But, I didn’t see much difference in warmup time (measured in the sandwich plate) with the Mishimoto vs. stock plate, or with the BOE pan insulated heavily or uninsulated (under easy driving conditions).

Maybe next month I will swap back to the stock pan and repeat some measurements, as it would be interesting to see if that makes a difference. And maybe i’ll try an idle test too.
 

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Oh, interesting. So even cold it pushed itself back out? Mine went in to the same position as the 180 thermostat that I was replacing so I figured I was good. Now I'm questioning that.
To recap, I had received the 200F thermostat with the pin loose. I put it into the base and it stayed in. Yesterday I tested the temperature of the oil coolers with the car idling from cold and it's clear that the thermostat is totally open all the time. So even if you can get the pin to stay in the base, it's still defective.
 

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My thermostat was the same way. I just put the pin back in and installed the plate. I also installed a temp sensor at the plate. Once my car temps come up, about 10 min, my oil stays at 200f give or take a few degrees. Hard running around 203 cursing 198 or so. That’s with a big aluminum oil pan with no insulation . I live in the south where it’s hot but it works about the same in the colder months just takes a little longer to warm up.
I am not the sharpest Tool in the shed but 180-200 it does not matter. Once I hit 180 I am all over the happy cam.
If everyone is worried about oil temp because of cam wipe I think we are making to big of a deal of oil temp. Oil temp may play a part but the big player is the way it oils the cams. That is the BIG problem. You best make sure you keep a good seal on that oil tube and check that it is flowing evenly and those last holes are getting oil. So yes oil temp is part of it but only part. I keep seals on hand so I can replace it after I pull the cam cover a few times.
Hope I don’t offend anyone. There is a lot of great information in this thread.
I have not had my coffee this morning.
 

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My thermostat was the same way. I just put the pin back in and installed the plate. I also installed a temp sensor at the plate. Once my car temps come up, about 10 min, my oil stays at 200f give or take a few degrees. Hard running around 203 cursing 198 or so. That’s with a big aluminum oil pan with no insulation . I live in the south where it’s hot but it works about the same in the colder months just takes a little longer to warm up.
I am not the sharpest Tool in the shed but 180-200 it does not matter. Once I hit 180 I am all over the happy cam.
If everyone is worried about oil temp because of cam wipe I think we are making to big of a deal of oil temp. Oil temp may play a part but the big player is the way it oils the cams. That is the BIG problem. You best make sure you keep a good seal on that oil tube and check that it is flowing evenly and those last holes are getting oil. So yes oil temp is part of it but only part. I keep seals on hand so I can replace it after I pull the cam cover a few times.
Hope I don’t offend anyone. There is a lot of great information in this thread.
I have not had my coffee this morning.
Thanks for your input! For those of us who are newer to the platform, could you speak more about your point of making sure the oil tube is sealed / oil is flowing everywhere it should? What does this mean and how do we check it / fix it if it is not working properly? You mentioned replacing a certain seal, for example. Thanks in advance!
 

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Thanks for your input! For those of us who are newer to the platform, could you speak more about your point of making sure the oil tube is sealed / oil is flowing everywhere it should? What does this mean and how do we check it / fix it if it is not working properly? You mentioned replacing a certain seal, for example. Thanks in advance!
Motor vehicle Yellow Gas Machine Auto part

In this picture you can see the oil tube that sprays oil onto the cam. The lobes on my intake cam that were wiped were the ones under the hole marked 1. When I blew air through the tube I found vary little flow coming through those holes. So I very carefully opened them ( a little at a time) till I had even flow. The part marked 2 goes down in to the head and has a seal on it, this was old and not sealing well. so I replaced it. I will find the part number later today. I found my cam was wiped 2 weeks after buying the car. Sense no one seems to be sure why they wipe I did several things to guard agents it happening agin; Mishimoto switch plate 200f tstat, MWR harden cams and their bigger rockers, oil temp gage, I don't have a cat so I run a zinc additive, and lastly never ever get on the happy cam till oil temp is 180+.
Hope this helps. There is a lot of knowledge here and some may disagree with me, thats fine listen to them too, they could be correct.
Sorry for the short highjack of the thread.
 

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My thermostat was the same way. I just put the pin back in and installed the plate. I also installed a temp sensor at the plate. Once my car temps come up, about 10 min, my oil stays at 200f give or take a few degrees. Hard running around 203 cursing 198 or so. That’s with a big aluminum oil pan with no insulation . I live in the south where it’s hot but it works about the same in the colder months just takes a little longer to warm up.
I am not the sharpest Tool in the shed but 180-200 it does not matter. Once I hit 180 I am all over the happy cam.
If everyone is worried about oil temp because of cam wipe I think we are making to big of a deal of oil temp. Oil temp may play a part but the big player is the way it oils the cams. That is the BIG problem. You best make sure you keep a good seal on that oil tube and check that it is flowing evenly and those last holes are getting oil. So yes oil temp is part of it but only part. I keep seals on hand so I can replace it after I pull the cam cover a few times.
Hope I don’t offend anyone. There is a lot of great information in this thread.
I have not had my coffee this morning.
Interesting that yours does regulate to the thermostat set point even though the pin was loose initially. I agree that the amount of focus on oil temps (and warmup time) is a bit much :)
 
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