75 v. 83 thermostats for 87-94 cars
05-30-2018, 11:11 PM
#31
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It reached the temperature I tuned the fully warmed up map to, so therefore with my setup, it was warm enough.
Correct, it not a fix to any problem. However, as I stated multiple times, there can be advantages to running a colder engine. But that's for a different thread.
Todd's Twin Turbo would never survive at his power levels at stock operating temperatures, at least not for every long.
"What Porsche intended" frankly is irrelevant. They were operating under regulations some of us don't care about....emissions, MPG etc..
I would never run a boosted 928 with a stock t-stat, but again, as I stated earlier for a 100% stock engine, not really any point in changing it.
Let's face it: this topic almost always comes up because someone has an issue with the cooling system and thinks a lower temperature thermostat will fix the problem. It won't. At best it will postpone the observance of the problem by a few minutes or until the weather gets hotter.
Todd's Twin Turbo would never survive at his power levels at stock operating temperatures, at least not for every long.
"What Porsche intended" frankly is irrelevant. They were operating under regulations some of us don't care about....emissions, MPG etc..
I would never run a boosted 928 with a stock t-stat, but again, as I stated earlier for a 100% stock engine, not really any point in changing it.
05-30-2018, 11:18 PM
#32
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My 89 runs temp gauge runs at the same as yours. I have the lower temp thermostat and at speed the temp is below the line, in traffic it will hit the line or go slightly above. When driven hard it will stay on the line until driving normally.
I had a temp issue and it was due to a bad thermostat seal. I replaced the seal and the thermostat with no further issues. The temp gauge always concerns me but it seems to be standard fair for Porsche, my Boxster and all previous 928s always seem to run on the high side
I had a temp issue and it was due to a bad thermostat seal. I replaced the seal and the thermostat with no further issues. The temp gauge always concerns me but it seems to be standard fair for Porsche, my Boxster and all previous 928s always seem to run on the high side
05-30-2018, 11:25 PM
#33
One thing all of you need to figure out is your actual temps, not what the gauge is telling you, but actual engine temps. Don’t ignore the gauge, but dont panic until you get an IR meter and take actual engine temps at the sensor on the water bridge. Then compare it to where the gauge reads and you will have an idea of how your car runs temp wise. Sticking new thermostats, changing radiators, putting on low pressure caps is not going to do dick unless you know your instrument indicator is anywhere near accurate.
I’ve had people panic about high temps on their car when it hits that last white line, and their car is sitting at 180. Had people insist I put in the lower temp ‘stat because they read crap here or on some website trying to sell parts, that that is what they needed. Get some actual numbers then try to figure out what your issue might be, chances are you don’t have an issue but got worried because someone told you that you have one and they were stupid.
I ran a lower temp ‘stat in my car for a while and the car never got up to temp, ran rich all the time because the computer told it that it was not hot enough and was still in the warm up loop. Bad mileage, bad performance, stupid idea. Put the 83c in and even have the same one in the car under boost and the temps are right where they need to be.
Be smart about it and get the car performing as it should from the factory, then dick around with other things. It’s your money to waste on all the other stuff, for no gain.
Low pressure coolant caps, that one has made me laugh for a long time.
I’ve had people panic about high temps on their car when it hits that last white line, and their car is sitting at 180. Had people insist I put in the lower temp ‘stat because they read crap here or on some website trying to sell parts, that that is what they needed. Get some actual numbers then try to figure out what your issue might be, chances are you don’t have an issue but got worried because someone told you that you have one and they were stupid.
I ran a lower temp ‘stat in my car for a while and the car never got up to temp, ran rich all the time because the computer told it that it was not hot enough and was still in the warm up loop. Bad mileage, bad performance, stupid idea. Put the 83c in and even have the same one in the car under boost and the temps are right where they need to be.
Be smart about it and get the car performing as it should from the factory, then dick around with other things. It’s your money to waste on all the other stuff, for no gain.
Low pressure coolant caps, that one has made me laugh for a long time.
05-30-2018, 11:26 PM
#34
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Todd's Twin Turbo would never survive at his power levels at stock operating temperatures, at least not for every long.
...
I would never run a boosted 928 with a stock t-stat, but again, as I stated earlier for a 100% stock engine, not really any point in changing it.
...
I would never run a boosted 928 with a stock t-stat, but again, as I stated earlier for a 100% stock engine, not really any point in changing it.
But, how, exactly, does fitting a lower-temperature thermostat solve that problem? Unless you've got some-sort of 'tricked-out' thermostat, all thermostats in a 928 will flow the same amount of water.
Baring that, I don't see how it solves the problem in steady-state. You either need more water flowing out of, or cooler water flowing into, the engine to carry away the extra heat. Once the lower-temp tstat is open it's OPEN.
A lower temp tstat might provide a little more transient margin for short load bursts if climatic conditions and time-from-start are low - and thus is core engine temp low. But, in steady-state high-output mode? Not.
What am I missing here?
05-31-2018, 12:05 AM
#35
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I don't know.
But even Sean above acknowledged his car ran too cool with a lower temp t-stat, again showing an example the computers need to be adjusted accordingly to actually make this work.
You keep talking about solving the problem, there isn't a "problem" just a desire to keep the engine as cool as possible (within reason).
"Once the lower-temp tstat is open it's OPEN."
- and once the temps fall below the bottom end of the colder t-stat threshold, it starts to close.....
If you run with a t-stat wide open (broken or modified) you'll see steady state temps even lower until you reach the maximum cooling capacity of the system.
But....to get back around to the topic at had, merchauser needs to:
1. Verify the actual temps
2. If still high fix that problem...
But even Sean above acknowledged his car ran too cool with a lower temp t-stat, again showing an example the computers need to be adjusted accordingly to actually make this work.
You keep talking about solving the problem, there isn't a "problem" just a desire to keep the engine as cool as possible (within reason).
"Once the lower-temp tstat is open it's OPEN."
- and once the temps fall below the bottom end of the colder t-stat threshold, it starts to close.....
If you run with a t-stat wide open (broken or modified) you'll see steady state temps even lower until you reach the maximum cooling capacity of the system.
But....to get back around to the topic at had, merchauser needs to:
1. Verify the actual temps
2. If still high fix that problem...
05-31-2018, 12:37 AM
#36
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"With the pre-'89 spade connectors to the cluster sender you can change the 'calibration' by unplugging the connectors and plugging them back in. "
Ok...id really like to know more about ^^this^^...is corrosion at the plug that much an issue to the gauge?
It may explain a few things...
Ok...id really like to know more about ^^this^^...is corrosion at the plug that much an issue to the gauge?
It may explain a few things...
05-31-2018, 02:30 AM
#37
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Todd's Twin Turbo would never survive at his power levels at stock operating temperatures, at least not for every long.
...
I would never run a boosted 928 with a stock t-stat, but again, as I stated earlier for a 100% stock engine, not really any point in changing it.
...
I would never run a boosted 928 with a stock t-stat, but again, as I stated earlier for a 100% stock engine, not really any point in changing it.
05-31-2018, 02:33 AM
#38
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"With the pre-'89 spade connectors to the cluster sender you can change the 'calibration' by unplugging the connectors and plugging them back in. "
Ok...id really like to know more about ^^this^^...is corrosion at the plug that much an issue to the gauge?
It may explain a few things...
Ok...id really like to know more about ^^this^^...is corrosion at the plug that much an issue to the gauge?
It may explain a few things...
05-31-2018, 09:01 AM
#40
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05-31-2018, 10:00 AM
#41
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Its amazing how people can miss-read things.
The benefit to installing a thermostat that opens earlier can be significant to a customer who has an older, tired radiator or has added power-adders to his car. Opening the thermostat earlier helps keep the radiator and engine from becoming heat-soaked.
Think of this: if the original radiator has some closed tubes and corrosion (a near certainty) then it needs to start cooling sooner thanit did when it was new, as it is virtually a smaller radiator now.
The benefit to lowering the cooling system pressures on an old radiator is to increase the life of the plastic end tanks on the old rad. Maybe the 928 owner can stretch the life of his original rad out a little longer before the plastic cracks by doing so.
According to you guys, if I'm just "trying to sell parts" I shouldn't offer these things? I should just sell radiators? No. I prefer to offer a variety of solutions to my customers, those that have the money for new radiators, and those that do not.
The benefit to installing a thermostat that opens earlier can be significant to a customer who has an older, tired radiator or has added power-adders to his car. Opening the thermostat earlier helps keep the radiator and engine from becoming heat-soaked.
Think of this: if the original radiator has some closed tubes and corrosion (a near certainty) then it needs to start cooling sooner thanit did when it was new, as it is virtually a smaller radiator now.
The benefit to lowering the cooling system pressures on an old radiator is to increase the life of the plastic end tanks on the old rad. Maybe the 928 owner can stretch the life of his original rad out a little longer before the plastic cracks by doing so.
According to you guys, if I'm just "trying to sell parts" I shouldn't offer these things? I should just sell radiators? No. I prefer to offer a variety of solutions to my customers, those that have the money for new radiators, and those that do not.
05-31-2018, 10:34 AM
#42
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Its amazing how people can miss-read things.
The benefit to installing a thermostat that opens earlier can be significant to a customer who has an older, tired radiator or has added power-adders to his car. Opening the thermostat earlier helps keep the radiator and engine from becoming heat-soaked.
Think of this: if the original radiator has some closed tubes and corrosion (a near certainty) then it needs to start cooling sooner thanit did when it was new, as it is virtually a smaller radiator now.
The benefit to lowering the cooling system pressures on an old radiator is to increase the life of the plastic end tanks on the old rad. Maybe the 928 owner can stretch the life of his original rad out a little longer before the plastic cracks by doing so.
According to you guys, if I'm just "trying to sell parts" I shouldn't offer these things? I should just sell radiators? No. I prefer to offer a variety of solutions to my customers, those that have the money for new radiators, and those that do not.
The benefit to installing a thermostat that opens earlier can be significant to a customer who has an older, tired radiator or has added power-adders to his car. Opening the thermostat earlier helps keep the radiator and engine from becoming heat-soaked.
Think of this: if the original radiator has some closed tubes and corrosion (a near certainty) then it needs to start cooling sooner thanit did when it was new, as it is virtually a smaller radiator now.
The benefit to lowering the cooling system pressures on an old radiator is to increase the life of the plastic end tanks on the old rad. Maybe the 928 owner can stretch the life of his original rad out a little longer before the plastic cracks by doing so.
According to you guys, if I'm just "trying to sell parts" I shouldn't offer these things? I should just sell radiators? No. I prefer to offer a variety of solutions to my customers, those that have the money for new radiators, and those that do not.
Offering the same parts with similar claims isn't much different, frankly it's irresponsible.
Justify it all you want, it's your hole to dig.
You had two choices:
1. Ignore this thread since it's obvious you are not here to offer up any advice on said problem
2. Jump in and turn this into another crap fest which will be driven off a cliff
I'm out, have fun guys.
05-31-2018, 10:42 AM
#43
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At no point did I discuss or recommend taking an over-heating car and trying to "fix it" with a thermostat and a radiator cap.
My suggestions follow regularly accepted guidelines for extending the life of older cars. Lower temp 'stats and lower pressure caps are a common small and easy modification to keep older radiators in the game a little longer (not to mention hoses and other parts).
Set your obvious bias aside and READ.
My suggestions follow regularly accepted guidelines for extending the life of older cars. Lower temp 'stats and lower pressure caps are a common small and easy modification to keep older radiators in the game a little longer (not to mention hoses and other parts).
Set your obvious bias aside and READ.
05-31-2018, 11:25 AM
#44
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Putting the correct warmer thermostat in my car solved several symptoms. Most important was that it replaced a lower-temp ‘stat that was stuck only partially open. I was initially “disappointed” to see that the temp gage moved to an almost rock-steady two needles below the third bar, after varying between just over the 170 line unloaded to mid-span or a little more under heat load, while the colder ‘stat was working.
Now, the engine gets up to temp much faster. The heater works. The needle is one width higher than before, but is stable at that spot over a large range of conditions. Perhaps the most significant change is in how the fans run— much less with the correct thermostat. Fans run based on radiator outlet temp back towards the engine. For whatever reason, the temp there is lower with the 85C ‘stat vs the 75C version. Another benefit: engine temp stays up with the AC running. The fan speed was responding to AC loading, and the 75C ‘stat was letting the engine temp drop.
Now, the engine gets up to temp much faster. The heater works. The needle is one width higher than before, but is stable at that spot over a large range of conditions. Perhaps the most significant change is in how the fans run— much less with the correct thermostat. Fans run based on radiator outlet temp back towards the engine. For whatever reason, the temp there is lower with the 85C ‘stat vs the 75C version. Another benefit: engine temp stays up with the AC running. The fan speed was responding to AC loading, and the 75C ‘stat was letting the engine temp drop.