Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 04-06-2003, 03:42 PM   #1
protouring72
Scooby Newbie
 
Member#: 13190
Join Date: Dec 2001
Location: 294whp
Vehicle:
02 Vishnu Stage 2

Default Any side effects from running a colder thermostat?

I was thinking of buying the zerosports thermostat to install in my car. Is there any side effect to this? I have a FMIC and was worried about the airflow to the radiator now. It doesnt run hot now, but summer's around the corner and it's going to get hot! I might even upgrade the radiator too. Will the car run too cold, and not be effecient? Thanks in advance for your knowledge!
john
* Registered users of the site do not see these ads.
protouring72 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 04-06-2003, 03:53 PM   #2
drees
Scooby Specialist
 
Member#: 25905
Join Date: Oct 2002
Chapter/Region: SCIC
Location: San Diego, CA
Vehicle:
2003 Silver Wagon
Tuned with Enginuity

Default

Generally, lower temp thermostats are a bad idea. If you need more cooling, get a bigger/more efficient radiator.

The problem with cooler thermostats is that the ECU may never think that the engine is fully warmed up and always run rich.

Hot engines are also generally more efficient (power and fuel economy) than a cooler engine.
drees is offline   Reply With Quote
Old 04-06-2003, 05:30 PM   #3
fastb18c
Scooby Newbie
 
Member#: 32177
Join Date: Jan 2003
Location: Oklahoma
Default

Unless you are producing WAY more power than stock, it isn't necessary and you won't see any benefit from it. Some people have had problems with low temp thermostats and ring seating, even at 15,000-20,000 miles.
fastb18c is offline   Reply With Quote
Old 04-06-2003, 05:34 PM   #4
Hit Man X
Scooby Specialist
 
Member#: 27787
Join Date: Oct 2002
Location: Mansfield, Texas, USA
Vehicle:
'02 WRX Sedan
Black

Default

I use 180* thermostats in most of my rides in lieu of the factory 195*'s. I haven't lost any performance or fuel economy with those. Besides just a bit cooler allows for a tad more timing.

160* is way too low, as your car will stay in open-loop (I think) where the computer believes the motor is still cold and dumps in more fuel to warm it up.

If you do one, a 180* is plenty low.
Hit Man X is offline   Reply With Quote
Old 04-06-2003, 05:40 PM   #5
SFastWRX
Scooby Specialist
 
Member#: 13379
Join Date: Dec 2001
Location: Los Angeles
Vehicle:
2002 WRX
I am Oz

Default

I believe the ECU considers the engine warmed up at 70 degrees C. The Zerosports thermostat doesn't open until 71C (160F), so there won't be a problem with the ECU. The stock thermostat opens at 78C (172 degrees F). The problems people have had with with colder thermostats are probably with the ones that open at a lower temp than this.

Necessary? no. Useful? hard to say for sure, but the engine will spend less time operating at 80+ degrees with it.
SFastWRX is offline   Reply With Quote
Old 04-06-2003, 05:52 PM   #6
Hit Man X
Scooby Specialist
 
Member#: 27787
Join Date: Oct 2002
Location: Mansfield, Texas, USA
Vehicle:
'02 WRX Sedan
Black

Default

I didn't know the stock WRX thermo was 172*F. That is way lower than any other vehicle I currently own, I would assume do to the increased heat created from the boost...?

I have seen many "hot-air" supercharged trucks that require a 160* thermo to resist detonation, so unless you have a significantly modified vehicle that is specifically tuned for a lower temp thermo, just skip it and save your cash for something else.
Hit Man X is offline   Reply With Quote
Old 04-06-2003, 06:15 PM   #7
WRXBob
Scooby Specialist
 
Member#: 12455
Join Date: Nov 2001
Location: CA
Vehicle:
02 WRX

Default

I monitored the engine coolant temp with the ODBII scanner. On the high way with normal cruising, the temp is around 176ºF. If I run the engine hard, the temp will goes to 186ºF. But if the car is idle in the traffic, the temp will be 204ºF. The problem is the engine fan will not comes on untill over 200ºF. On my other car, I installed a lower temp stat and modify the temp sensor with a resistor to full the ECU thinking that the engine already reached full temp and make the fan comes on sooner.
WRXBob is offline   Reply With Quote
Old 04-07-2003, 02:08 PM   #8
drees
Scooby Specialist
 
Member#: 25905
Join Date: Oct 2002
Chapter/Region: SCIC
Location: San Diego, CA
Vehicle:
2003 Silver Wagon
Tuned with Enginuity

Default

Quote:
Originally posted by WRXBob
I monitored the engine coolant temp with the ODBII scanner. On the high way with normal cruising, the temp is around 176ºF. If I run the engine hard, the temp will goes to 186ºF. But if the car is idle in the traffic, the temp will be 204ºF. The problem is the engine fan will not comes on untill over 200ºF. On my other car, I installed a lower temp stat and modify the temp sensor with a resistor to full the ECU thinking that the engine already reached full temp and make the fan comes on sooner.
Wow. Given this information it seems that the best thing to do would be to trick the engine fan to kick in a bit sooner. Although at high temps and engine loads this may cause the fan to kick in at speed which wouldn't be a good thing.

At what temp does the engine fan kick off after having been on?
drees is offline   Reply With Quote
Old 04-07-2003, 06:29 PM   #9
protouring72
Scooby Newbie
 
Member#: 13190
Join Date: Dec 2001
Location: 294whp
Vehicle:
02 Vishnu Stage 2

Default

so basically, what i gather from all this info is that the thermostat is not a good idea, having to do with engine warm up and open/closed loop operation. And if i need the extra cooling, to go with an aftermarket radiator, such as the PWR or Fluidyne.
protouring72 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Any Ill effects from just Up-Pipe? slack2012 Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 18 08-27-2002 09:44 PM
Any side effects of getting springs w/o shocks?? BlackWagon Brakes, Steering & Suspension 11 07-10-2002 01:14 AM
ProECM -- any side effects? V6 Normally Aspirated Powertrain 66 06-16-2002 03:12 AM
ProECM -- any side effects? V6 Transmission (AT/MT) & Driveline 1 05-25-2002 12:30 AM
Any downforce effect from Wing/Spoiler? Joe Lee Interior & Exterior Modification 2 08-19-2001 02:10 AM

All times are GMT -4. The time now is 10:45 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.