Here is the data from my preliminary testing and driving impressions of the 170* degree hybrid stat that Jmproductions built.
Info and background on this thermostatstat can be found in the thread below, with specific details on page 3 of that thread.
http://www.svtperformance.com/forums/showthread.php?t=510129
My current cooling setup is a follows:
OEM 180* stat with (4) 1/8 in holes drilled in it
Fluidyne radaitor
80% distilled water, 20% coolant and a bottle of Water Wetter.
Fan settings:
190* low on
196* high on
185* high off
180* low off.
The only thing that was changed for these tests was the thermostat.
I started with a warm up test by letting the car idle in my garage until it got up to temp. Then when the fan kicked on at 190* I recorded the time it took for the temp to drop from 190* to 180*
4 hole OEM stat -
80* ambient
82* cold coolant temp at beginning of test.
170* - 10:41
180* - 13:12
190* - 14:50
190* to 180* recovery - 1:08
170 Hybrid stat -
81* ambient
84* cold coolant temp at beginning of test.
170* - 9:13
180* - 13:25
190* - 15:02
190* to 180* recovery - 1:08
The results are about what I expected for the 170* stat. The car stayed at 176* for over 2 minutes until the radiator was heatsoaked, and then the temp began to rise again. To optimize the hybrid stat you will want to adjust the fan settings a bit lower. The higher fan settings are also a disadvantage for the 170 hybrid stat in my warm up tests.
Fan settings you will want to use for the 170 hybrid stat:
184* low on
190* high on
180* high off
183* low off.
These are a good place to start. You can adjust them depending on climate, and how much you are annoyed by the sound of the fan.
Driving impressions:
The car runs 3-5 degrees cooler on the highway, and recovery times in traffic have dropped by roughly 25%. This is hard to quantify scientifically because there are so many variables, but the car did cool down faster when the fan came on in traffic. I drove for about an hour with each stat, taking notes and recording times in city driving. Highway recovery was about the same as with the OEM drilled stat. Also the coolant temp stayed more consistent. The coolant temp with the 170 hybrid was about a 10 degree swing where the drilled OEM was about a 15+ degree swing in city driving.
Why is the 170 degree hybrid better?
The key reason this thermostat works better is because of the bypass block off. The OEM thermostat does not fully open until around 212 degrees. We were fixing this by drilling holes in it to get more coolant flow at lower temps. We still had the problem of the bypass not being fully closed off until 212, which caused the system to let coolant constantly bypass the radiator. Many aftermarket stats that you buy from the auto parts store are not high flow, or do not have the correct sized bypass block off plate. The hybrid is a 100% compatible fitment, and fully opens by 180 degrees.
If you have any questions about the hybrid stat or this testing please let me know.
Info and background on this thermostatstat can be found in the thread below, with specific details on page 3 of that thread.
http://www.svtperformance.com/forums/showthread.php?t=510129
My current cooling setup is a follows:
OEM 180* stat with (4) 1/8 in holes drilled in it
Fluidyne radaitor
80% distilled water, 20% coolant and a bottle of Water Wetter.
Fan settings:
190* low on
196* high on
185* high off
180* low off.
The only thing that was changed for these tests was the thermostat.
I started with a warm up test by letting the car idle in my garage until it got up to temp. Then when the fan kicked on at 190* I recorded the time it took for the temp to drop from 190* to 180*
4 hole OEM stat -
80* ambient
82* cold coolant temp at beginning of test.
170* - 10:41
180* - 13:12
190* - 14:50
190* to 180* recovery - 1:08
170 Hybrid stat -
81* ambient
84* cold coolant temp at beginning of test.
170* - 9:13
180* - 13:25
190* - 15:02
190* to 180* recovery - 1:08
The results are about what I expected for the 170* stat. The car stayed at 176* for over 2 minutes until the radiator was heatsoaked, and then the temp began to rise again. To optimize the hybrid stat you will want to adjust the fan settings a bit lower. The higher fan settings are also a disadvantage for the 170 hybrid stat in my warm up tests.
Fan settings you will want to use for the 170 hybrid stat:
184* low on
190* high on
180* high off
183* low off.
These are a good place to start. You can adjust them depending on climate, and how much you are annoyed by the sound of the fan.
Driving impressions:
The car runs 3-5 degrees cooler on the highway, and recovery times in traffic have dropped by roughly 25%. This is hard to quantify scientifically because there are so many variables, but the car did cool down faster when the fan came on in traffic. I drove for about an hour with each stat, taking notes and recording times in city driving. Highway recovery was about the same as with the OEM drilled stat. Also the coolant temp stayed more consistent. The coolant temp with the 170 hybrid was about a 10 degree swing where the drilled OEM was about a 15+ degree swing in city driving.
Why is the 170 degree hybrid better?
The key reason this thermostat works better is because of the bypass block off. The OEM thermostat does not fully open until around 212 degrees. We were fixing this by drilling holes in it to get more coolant flow at lower temps. We still had the problem of the bypass not being fully closed off until 212, which caused the system to let coolant constantly bypass the radiator. Many aftermarket stats that you buy from the auto parts store are not high flow, or do not have the correct sized bypass block off plate. The hybrid is a 100% compatible fitment, and fully opens by 180 degrees.
If you have any questions about the hybrid stat or this testing please let me know.