DIY thermostat delete
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From: Planet Kolob
I did this and the car has been running a lot cooler. I'm logging coolant peak temps of 184 degree F in nearly 100 degree weather and before it would peak 202+. I also have a full coolant bypass so that also contributes to the lower temps.


Not saying that what you did is bad or doesn't work, but on some engines it can actually be risky. Basically the water flows too fast through the radiator and doesn't allow proper cooling. Engines CAN actually run hotter that way. A nismo stat would be a safer choice. I know my vq40 runs a max of about 181F with it.
However that aside, they do cost $100+ dollars. And since you are monitoring your temps and the stat delete appears to be doing well on your engine, I guess on the vq35 the flow isn't too bad and it still allows good cooling. Good job guy.
However that aside, they do cost $100+ dollars. And since you are monitoring your temps and the stat delete appears to be doing well on your engine, I guess on the vq35 the flow isn't too bad and it still allows good cooling. Good job guy.
This was a trick on the mustangs years ago. Way back on the 5.0s. I can't remember what the deal was and why it was a bad idea.
I guess as long as you monitor the temp it should be ok.
Does this affect long cruises or stop and go?
I guess as long as you monitor the temp it should be ok.
Does this affect long cruises or stop and go?
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From: Planet Kolob
I'm logging the temp through an OBD scanner.
Not saying that what you did is bad or doesn't work, but on some engines it can actually be risky. Basically the water flows too fast through the radiator and doesn't allow proper cooling. Engines CAN actually run hotter that way. A nismo stat would be a safer choice. I know my vq40 runs a max of about 181F with it.
However that aside, they do cost $100+ dollars. And since you are monitoring your temps and the stat delete appears to be doing well on your engine, I guess on the vq35 the flow isn't too bad and it still allows good cooling. Good job guy.
However that aside, they do cost $100+ dollars. And since you are monitoring your temps and the stat delete appears to be doing well on your engine, I guess on the vq35 the flow isn't too bad and it still allows good cooling. Good job guy.
I noticed that the temp gets lower the faster the car moves. Say 60mph with light throttle I see dip into to the low 170s. NA with a bigger radiator and stronger fans, I'm expecting to hit 160s.
Last edited by Andrei; Jul 16, 2011 at 08:07 AM.
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From: Planet Kolob
The fact that I am seeing lower coolant temp is very good in my point of view.
A thermostat reduces cold start emissions by bringing a motor up to operating temperature faster by staying closed before the operating temperature is reached. And it also means you get heat faster out of the AC.
The fact that I am seeing lower coolant temp is very good in my point of view.
The fact that I am seeing lower coolant temp is very good in my point of view.
A thermostat reduces cold start emissions by bringing a motor up to operating temperature faster by staying closed before the operating temperature is reached. And it also means you get heat faster out of the AC.
The fact that I am seeing lower coolant temp is very good in my point of view.
The fact that I am seeing lower coolant temp is very good in my point of view.
I'm still baffled by doing this. The stock opens between 170 - 180. If you run the coolant full time you won't give the coolant a chance to cool off in the radiator.
Why don't you just get an Nismo stat? They open at 150ish.
Still not sure if this is a really good idea. The engine needs to get to a certain temp so parts can expand and operate normal.
I hope not but I see a piston issue in the future.
Why don't you just get an Nismo stat? They open at 150ish.
Still not sure if this is a really good idea. The engine needs to get to a certain temp so parts can expand and operate normal.
I hope not but I see a piston issue in the future.
I'm still baffled by doing this. The stock opens between 170 - 180. If you run the coolant full time you won't give the coolant a chance to cool off in the radiator.
Why don't you just get an Nismo stat? They open at 150ish.
Still not sure if this is a really good idea. The engine needs to get to a certain temp so parts can expand and operate normal.
I hope not but I see a piston issue in the future.
Why don't you just get an Nismo stat? They open at 150ish.
Still not sure if this is a really good idea. The engine needs to get to a certain temp so parts can expand and operate normal.
I hope not but I see a piston issue in the future.
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From: Planet Kolob
You have more engine wear on start up than any other time in a engine's life cycle... running cool is relative. The longer it takes the engine to achieve the temperature it requires the more wear your inducing on the engine, some engines start developing sludge at this state of the engine's life cycle(if not changed often). The A/C system has nothing to do with the cars cooling system but Heating does. It's pretty obvious that if your not racing the vehicle or can't afford a thermostat b/c your is bad... their's no reason to replace the thermostat.
I'm still baffled by doing this. The stock opens between 170 - 180. If you run the coolant full time you won't give the coolant a chance to cool off in the radiator.
Why don't you just get an Nismo stat? They open at 150ish.
Still not sure if this is a really good idea. The engine needs to get to a certain temp so parts can expand and operate normal.
I hope not but I see a piston issue in the future.
Why don't you just get an Nismo stat? They open at 150ish.
Still not sure if this is a really good idea. The engine needs to get to a certain temp so parts can expand and operate normal.
I hope not but I see a piston issue in the future.
Last edited by Andrei; Jul 17, 2011 at 08:03 PM.
Anyone know what temperature the coolant is actually supposed to be at? I'm guessing the engineers didn't just pull a number out of their *** and say that is what we should set the thermostat at.







