Need ideas on how to bring coolant temps down on track
#1
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I've read the thread on cooling, but still have some questions some of you may be able to help with.
I have an 02 with a Rotrex SC. It is mainly used for track days. I have the intercooled Rotrex kit with an AEM FIC piggy and 420 RX8 injectors and a good tune. Smaller pulley..10 PSI, 207 RWHP. Stock 12" x 6" FMIC, AC condenser removed and the Rotrex oil cooler in front of an FM crossflow radiator. Stock fans with the AC fan wired to come on with the driver side fan (just did this and haven't tried on track yet). I had highish temps on track last year 220 was quite common. It makes it hard to concentrate on driving while worrying about my temps. I also have an FM oil cooler. I ran 100% distilled water with redline water wetter. My heater is still functional. I have a vented hood. I have ducted around the radiator the best I can. 180* Stant Superstat. I do NOT have a reroute. Some of my ideas to lower my temps are:
1.) Do a reroute and head gasket from 90-99 (cannot figure out how this will lower my temperatures, seems like it could only even them out)
2.) PWR fin and tube IC in lieu of the plate and frame (seems they allow more air through to the radiator) I actually picked up an MSM IC to try (it is a fin and tube) it’s only 8” X 8” …maybe enough for a Rotrex?
3.) Relocate Rotrex oil cooler to wheel well. I like this idea but I already have brake ducts in my fog light openings and IC piping in there. It will be one hell of a trick to get that all in there and get enough airflow to the Rotrex cooler.
What are your thoughts???
I have an 02 with a Rotrex SC. It is mainly used for track days. I have the intercooled Rotrex kit with an AEM FIC piggy and 420 RX8 injectors and a good tune. Smaller pulley..10 PSI, 207 RWHP. Stock 12" x 6" FMIC, AC condenser removed and the Rotrex oil cooler in front of an FM crossflow radiator. Stock fans with the AC fan wired to come on with the driver side fan (just did this and haven't tried on track yet). I had highish temps on track last year 220 was quite common. It makes it hard to concentrate on driving while worrying about my temps. I also have an FM oil cooler. I ran 100% distilled water with redline water wetter. My heater is still functional. I have a vented hood. I have ducted around the radiator the best I can. 180* Stant Superstat. I do NOT have a reroute. Some of my ideas to lower my temps are:
1.) Do a reroute and head gasket from 90-99 (cannot figure out how this will lower my temperatures, seems like it could only even them out)
2.) PWR fin and tube IC in lieu of the plate and frame (seems they allow more air through to the radiator) I actually picked up an MSM IC to try (it is a fin and tube) it’s only 8” X 8” …maybe enough for a Rotrex?
3.) Relocate Rotrex oil cooler to wheel well. I like this idea but I already have brake ducts in my fog light openings and IC piping in there. It will be one hell of a trick to get that all in there and get enough airflow to the Rotrex cooler.
What are your thoughts???
#4
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In addition to V's comments:
- Better ducting. Post photos of what you've got right now? Consider modifying the front crash structure to allow better airflow to the radiator (I'd outsource this to a race fabricator rather than DIY).
- Remove the AC fan, it's just in the way at track speeds. Mount the oil cooler on the back of the rad where the other fan used to be.
- TSE rad gives more cooling than FM.
--Ian
- Better ducting. Post photos of what you've got right now? Consider modifying the front crash structure to allow better airflow to the radiator (I'd outsource this to a race fabricator rather than DIY).
- Remove the AC fan, it's just in the way at track speeds. Mount the oil cooler on the back of the rad where the other fan used to be.
- TSE rad gives more cooling than FM.
--Ian
#5
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A reroute increases cooling for the following reasons:
1. The coolant picks up more heat from the engine because it has to traverse all cylinders. No shortcuts allowed.
2. With the spacer + Kia waterneck reroute, the water balance is altered so that more water flows to the radiator rather than the heater core. You'll notice after installing a reroute that your heater doesn't work as well. The increased flow to the radiator results in quite a bit more heat transfer. I don't know whether those with remote thermostats like M-tuned also see this effect.
3. Going to the earlier HG opens up flow passages through the engine. Again, more flow = more cooling. Mazda achieved the heat transfer balance in the 01+ engines by closing off holes in the HG. So, good at OEM levels, not so good at your levels.
Good luck. Looking at your mod list, I'd recommend spending less time on FM's website and more time here. FM has some good stuff, but choose carefully.
1. The coolant picks up more heat from the engine because it has to traverse all cylinders. No shortcuts allowed.
2. With the spacer + Kia waterneck reroute, the water balance is altered so that more water flows to the radiator rather than the heater core. You'll notice after installing a reroute that your heater doesn't work as well. The increased flow to the radiator results in quite a bit more heat transfer. I don't know whether those with remote thermostats like M-tuned also see this effect.
3. Going to the earlier HG opens up flow passages through the engine. Again, more flow = more cooling. Mazda achieved the heat transfer balance in the 01+ engines by closing off holes in the HG. So, good at OEM levels, not so good at your levels.
Good luck. Looking at your mod list, I'd recommend spending less time on FM's website and more time here. FM has some good stuff, but choose carefully.
Last edited by hornetball; 05-14-2015 at 03:59 PM.
#10
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In addition to V's comments:
- Better ducting. Post photos of what you've got right now? Consider modifying the front crash structure to allow better airflow to the radiator (I'd outsource this to a race fabricator rather than DIY).
- Remove the AC fan, it's just in the way at track speeds. Mount the oil cooler on the back of the rad where the other fan used to be.
- TSE rad gives more cooling than FM.
--Ian
- Better ducting. Post photos of what you've got right now? Consider modifying the front crash structure to allow better airflow to the radiator (I'd outsource this to a race fabricator rather than DIY).
- Remove the AC fan, it's just in the way at track speeds. Mount the oil cooler on the back of the rad where the other fan used to be.
- TSE rad gives more cooling than FM.
--Ian
Will do a reroute also (with 90-99 head gasket)
#13
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And from the Cooling Thread, Post#378: "To add another data point, we ran a stock plastic end tank automatic radiator fully ducted from an airdam with a reroute and blocked open thermostat on a stock horsepower racecar for 14 hours this weekend. Coolant temps never rose above 190 F on a 85 F ambient day. "
?
#18
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When you have a big outlet however theres more water flowing through to pick up the heat so the overall temp is lower.
You have a fixed heat output from the engine and you're changing the amount of water you throw at it. Does that make sense?
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The coolant flows through the heater core much slower since the pipes are smaller and of course the heater core blocks flow as well. This gives the water more time to pick up heat from the 2nd, 3rd, and 4th cylinder before going out. Since the sensor is at that outlet the measurement is high.
When you have a big outlet however theres more water flowing through to pick up the heat so the overall temp is lower.
You have a fixed heat output from the engine and you're changing the amount of water you throw at it. Does that make sense?
When you have a big outlet however theres more water flowing through to pick up the heat so the overall temp is lower.
You have a fixed heat output from the engine and you're changing the amount of water you throw at it. Does that make sense?