996 Cooling solutions
#16
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Thanks for the info Macster. I live in Dallas where its regularly over 100F which it will be today. This is my first summer with this particular car. My temp gauge seems to be running around the 205 - 212 range in the heat of the day. This would be the needle being on the right side of the zero but not over the next line which is 215. I assume this is normal then. Can others that live in hot climates let me know what thier coolant temp gauge normally runs at?
#17
Three Wheelin'
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I did Jim's radiator fan mod and it lowers the temps by 15-20 celcius...!! I also have the 3rd radiator and it does nothing for in town driving... the fan mod works better..... if your tracking do both for more protection.
#18
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Thanks for the info Macster. I live in Dallas where its regularly over 100F which it will be today. This is my first summer with this particular car. My temp gauge seems to be running around the 205 - 212 range in the heat of the day. This would be the needle being on the right side of the zero but not over the next line which is 215. I assume this is normal then. Can others that live in hot climates let me know what thier coolant temp gauge normally runs at?
I think an air-oil cooler would take a lot of load off the cooling system. Maybe I'll add one.
#19
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Thanks Doug. I did a lot of driving the last couple days in 101 - 104 F temps and tried wwest's recommendation of using the recirculate mode. It ran cooler mostly around 200 - 205F on the gauge while up to speed which I consider good for those conditions. I did hear the high speed fans kick on when stopping at a red light or in traffic. My radiators are also clean and coolant system has been pressure checked.
#20
Three Wheelin'
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just do the high speed fan mod... on a super hot day the fan mod will get you down to 85C guaranteed... without fans I'm @ 104C (as display on HVAC) after running the fans for 20 minutes I go as low as 83C... just keep them on in city driving... works like a charm...
#21
Rocky Mountain High
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I drove my car hard for the past two days in the mountains at about 95 degrees F. My temp never got above 180, even when pushing the car pretty hard. FWIW, I had new radiator fans and relays as well as a new water pump installed last year.
#22
Three Wheelin'
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#23
Drifting
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If you want your engine to remain cooler (190F rather than 220), simply do my fan switch mod. No need for heaveier 3rd radiator.
Radiator Fan and Engine Compartment Fan Switch Mod
The 3.4 996 runs extremely hot when driving around town in temperatures higher than 75 degrees. This mod is a way to reduce coolant temps back to a safer level, helping to reduce oil temps and improving performance.
The mod consists of installing a switch that will allow you to turn on the high speed radiator fans at any time, while maintaining the automatic operation of the fans. We do the same for the engine compartment fan.
Radiator Fans
Connect a wire to the ground of the 2 high speed fan relays located on the relay carrier located in the driver’s side foot well. The relays are #20 and #22. Feed this wire to where your switch will be located. Connect the wire to one side of the switch. Connect another wire from the other contact on the switch and then connect the other end of this wire to a chassis ground point.
With key on, this switch will now immediately turn on both radiator fans providing maximum cooling. When you turn the key off, the fans will continue to run for about 5 seconds until the relay shuts down. Your fan operation remains normal when the switch is off.
Engine Compartment Fan
Connect a wire to the ground of the relay located in the relay carrier behind the passenger seat, driver’s side. Relay #8. . Feed this wire to where your switch will be located. I simply fed the wire along the driver’s side of the car and under the door sill. Connect the wire to one side of the switch. Connect another wire from the other contact on the switch and connect the other end of this wire to a chassis ground point.
With key on, this switch will now immediately turn on the fan drawing air into the engine compartment. When you turn the key off, the fan will continue to run for about 5 seconds until the relay shuts down. Your fan operation remains normal when the switch is off. This mod helps keep the engine compartment much cooler when driving around town and is particularly beneficial to any engine that draws its intake air from inside the engine compartment, such as the EVO SC.
If you are adventurous, you can automate the operation of these switches so they will switch off at a specific speed, or operate when vacuum is present only, etc. You can choose any style switch you want and even use Porsche switches. I simply used 2 toggle switches that I installed in the batwing,
Jim
Radiator Fan and Engine Compartment Fan Switch Mod
The 3.4 996 runs extremely hot when driving around town in temperatures higher than 75 degrees. This mod is a way to reduce coolant temps back to a safer level, helping to reduce oil temps and improving performance.
The mod consists of installing a switch that will allow you to turn on the high speed radiator fans at any time, while maintaining the automatic operation of the fans. We do the same for the engine compartment fan.
Radiator Fans
Connect a wire to the ground of the 2 high speed fan relays located on the relay carrier located in the driver’s side foot well. The relays are #20 and #22. Feed this wire to where your switch will be located. Connect the wire to one side of the switch. Connect another wire from the other contact on the switch and then connect the other end of this wire to a chassis ground point.
With key on, this switch will now immediately turn on both radiator fans providing maximum cooling. When you turn the key off, the fans will continue to run for about 5 seconds until the relay shuts down. Your fan operation remains normal when the switch is off.
Engine Compartment Fan
Connect a wire to the ground of the relay located in the relay carrier behind the passenger seat, driver’s side. Relay #8. . Feed this wire to where your switch will be located. I simply fed the wire along the driver’s side of the car and under the door sill. Connect the wire to one side of the switch. Connect another wire from the other contact on the switch and connect the other end of this wire to a chassis ground point.
With key on, this switch will now immediately turn on the fan drawing air into the engine compartment. When you turn the key off, the fan will continue to run for about 5 seconds until the relay shuts down. Your fan operation remains normal when the switch is off. This mod helps keep the engine compartment much cooler when driving around town and is particularly beneficial to any engine that draws its intake air from inside the engine compartment, such as the EVO SC.
If you are adventurous, you can automate the operation of these switches so they will switch off at a specific speed, or operate when vacuum is present only, etc. You can choose any style switch you want and even use Porsche switches. I simply used 2 toggle switches that I installed in the batwing,
Jim
#24
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Don't the fans run on high when the A/C is on regardless???
#25
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#26
Rocky Mountain High
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I think they always run when the a/c is on...
#27
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I put 2 micro switches (front/rear fan), the ground is hooked up behind the panel braces, there are some screws behind there attached to the body. Unplug the fan relay and tie the ground on the relay prong and put back in the socket... its a no brainer.
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#28
Drifting
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[QUOTE=redridge;9638509]Jim is prob not gonna answer, he's been awol for awhile... I think he misses Ben. ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
I put 2 micro switches (front/rear fan), the ground is hooked up behind the panel braces, there are some screws behind there attached to the body. Unplug the fan relay and tie the ground on the relay prong and put back in the socket... its a no brainer.
Thanks ! thats helpful.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
I put 2 micro switches (front/rear fan), the ground is hooked up behind the panel braces, there are some screws behind there attached to the body. Unplug the fan relay and tie the ground on the relay prong and put back in the socket... its a no brainer.
Thanks ! thats helpful.
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#29
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I did the jumper from the low relay to the high relay for each side so when low speed kicks in high speed comes on by default and added one switch for both the radiator fans and the engine compartment fan on the bat wing.
I use a mix of 70% water, 30% coolant and added 2 bottles of Water Wetter. My car now stays at 96 to 99 degrees C on the A/C display with that trick with the buttons. Its a huge accomplishment because a couple of years ago it was cooking hot at 110 to 115C with straight coolant, no fan hacks or switch.
I use a mix of 70% water, 30% coolant and added 2 bottles of Water Wetter. My car now stays at 96 to 99 degrees C on the A/C display with that trick with the buttons. Its a huge accomplishment because a couple of years ago it was cooking hot at 110 to 115C with straight coolant, no fan hacks or switch.