Long distance driving.
#23
FWIW, I had a completely stock 93' 1.6l that would start creeping towards overheating at highway speeds over--uh--130 kph. The problem was completely solved by replacing the thermostat with a new one. This is what I would try first--it's a 20 minute check to see if your cooling system is being exceeded because of your setup or if it is already compromised.
#24
Some of the ducting can be done easily with some flexible plastic sheeting and zip ties. Just cut slots and holes to wrap closely around intercooler piping. You want to seal from the mouth of the car to the radiator so air can't bypass it.
Shrouding the fans is another easy diy project. Just make sure you have space between the shroud and the back of the radiator and seal between the shroud and the edges of the radiator.
There are good threads here on both treatments/remedies. May also want to duct the hood to encourage more air flow.
Shrouding the fans is another easy diy project. Just make sure you have space between the shroud and the back of the radiator and seal between the shroud and the edges of the radiator.
There are good threads here on both treatments/remedies. May also want to duct the hood to encourage more air flow.
#25
Some of the ducting can be done easily with some flexible plastic sheeting and zip ties. Just cut slots and holes to wrap closely around intercooler piping. You want to seal from the mouth of the car to the radiator so air can't bypass it.
Shrouding the fans is another easy diy project. Just make sure you have space between the shroud and the back of the radiator and seal between the shroud and the edges of the radiator.
There are good threads here on both treatments/remedies. May also want to duct the hood to encourage more air flow.
Shrouding the fans is another easy diy project. Just make sure you have space between the shroud and the back of the radiator and seal between the shroud and the edges of the radiator.
There are good threads here on both treatments/remedies. May also want to duct the hood to encourage more air flow.
#27
Want fries with that?
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Since we're on the topic of long-distance driving, I just drove down to visit my sister at college and it was a little rocky (~300 miles). Mainly due to the fact that the manifold-turbo studs came loose a couple times. I had to stop twice to tighten them up. It is very annoying. I'm going to a hardware store with her today and buying bolts to double up, I'm hoping this will help out, anyone done this? I've seen BEGI installed kits do this, so there must be something to it.
NOTE: On this drive I was cruising at 85ish, so like 4,500rpms. Higher than I usually am. Coolant temps steady at 197 pretty much the whole way, MAT anywhere from 69-76, depending on the ambient temp. Couple times in boost, probably 3 pulls, otherwise pulling ~15-12lbs vac most of the time.
NOTE: On this drive I was cruising at 85ish, so like 4,500rpms. Higher than I usually am. Coolant temps steady at 197 pretty much the whole way, MAT anywhere from 69-76, depending on the ambient temp. Couple times in boost, probably 3 pulls, otherwise pulling ~15-12lbs vac most of the time.
#28
Boost Pope
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The turbo is always spinning. It spins at idle, it spins at cruise, it spins at WOT. Depending on the size of the turbo, the design of the exhaust system, and quite a lot of other variables, it's even possible that it may be spinning fast enough at high-speed cruise to make some amount of "boost" between the compressor and the partially closed throttle plate.
But none of this should be causing overheating. I have driven my turbo car (which, incidentally, is missing most of the front shrouding) from San Diego, California to Phoenix, Arizona and back, twice, both times in the summer. You may not be familiar with the geography of the western US, but this is a roughly 600 km trip that goes across some mountains which are over 1.5km in height, and through a desert in which the temperatures in the summertime are commonly 40-45°C.
So, if you are overheating, something is wrong. Maybe there's a pressure leak in the cooling system, maybe your thermostat is crap, maybe there's a blockage somewhere...
A good start would be a coolant reroute, which fixes a major shortcoming in the design of the Miata cooling system, restoring it to the way it was when this engine was originally installed in FWD cars, specifically, removing the thermostat and moving it to the back of the head and blocking off the port on the front of the head. There are a couple of commercially-available kits to help you do this, if you don't want to assemble it yourself:
http://www.etdracing.com/m-tuned/pro...products_id=85
http://www.bellengineering.net/produ...roducts_id=300
Big, aluminum radiators are also very pretty, and some folks believe that they improve cooling performance as well.
Nearly a worst-case scenario. With the top down, the aerodynamics of the car go completely to ****. The engine has to produce far more power to propel the vehicle through the air at 140km/hr with the top down than it would have to make do to the same with the top and windows up while also powering the aircon. It should still be able to do this without overheating, just pointing out that you may be unknowingly aggravating whatever problem exists.
#29
mkturbo.com
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Since we're on the topic of long-distance driving, I just drove down to visit my sister at college and it was a little rocky (~300 miles). Mainly due to the fact that the manifold-turbo studs came loose a couple times. I had to stop twice to tighten them up. It is very annoying. I'm going to a hardware store with her today and buying bolts to double up, I'm hoping this will help out, anyone done this? I've seen BEGI installed kits do this, so there must be something to it.
NOTE: On this drive I was cruising at 85ish, so like 4,500rpms. Higher than I usually am. Coolant temps steady at 197 pretty much the whole way, MAT anywhere from 69-76, depending on the ambient temp. Couple times in boost, probably 3 pulls, otherwise pulling ~15-12lbs vac most of the time.
NOTE: On this drive I was cruising at 85ish, so like 4,500rpms. Higher than I usually am. Coolant temps steady at 197 pretty much the whole way, MAT anywhere from 69-76, depending on the ambient temp. Couple times in boost, probably 3 pulls, otherwise pulling ~15-12lbs vac most of the time.
#31
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Eerrrghhh these track ****** (savington and hustler) are recommending solutions for racing, NOT for what is essentially just daily driving, albeit high speed driving. You don't need ducting for day to day driving. It might fix your problem but I think that first you should swap out your thermostat. It is much less effort and is likely the real problem.
I also think you don't need a reroute and you don't need a big aluminum radiator.
I think your problem is most likely just your thermostat.
I also think you don't need a reroute and you don't need a big aluminum radiator.
I think your problem is most likely just your thermostat.
#32
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Since we're on the topic of long-distance driving, I just drove down to visit my sister at college and it was a little rocky (~300 miles). Mainly due to the fact that the manifold-turbo studs came loose a couple times. I had to stop twice to tighten them up. It is very annoying.
The solution is apparently incolnel studs with resbond.
#33
Try replacing your coolant with pure water + Redline Water Wetter, put the fans working in parallel, a lower temperature thermostat, a 1.3 bar Cap...
A bigger aluminum radiator as a Koyo or PWR will help too as well as the re-routing.
Good luck.
Ben.
A bigger aluminum radiator as a Koyo or PWR will help too as well as the re-routing.
Good luck.
Ben.
Last edited by miatasc; 10-17-2010 at 03:41 PM.
#34
An extraction hood is probably a luxury, but it completely eliminated my highway speed w/AC problem. Worked so well that the radiator fans no longer turn on while going down the highway. When I turn the A/C on, my temp gauge goes DOWN (and I'm not exaggerating to make a point, either), presumably because with the addition of the extraction hood, the additional air that the fans pull through when the A/C is on is far superior to the A/C Condenser in the coolant-temp tug-of-war...and that miata has the coldest A/C system of any car I've ever owned - all the way back to the pre R134 days.
#35
I don't have ac, but my cooling system is completely stock with the stock 95 radiator and ive done a 200 mile drive many times with 0 problems, going between 75-125 mph the whole way, and just did the 5 hour, 300 drive from san diego to slo with absolutely no problems, also going about 75-80 the whole way. I would definitely check things like the thermostat first, probably a simple solution. I have the original belly pan in place, no additional ducting, no reroute, etc.
#39
Humidity shouldnt have any effect whatsoever on the cars ability to cool - our cars do not use evaporative cooling. Actually, the humid air should require more energy to increase the same temperature as dry air because you're increasing the temperature of the water content in the air as well. The cooling effect of humid air should be better, not worse, than the same air in dry form.
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OP, you still should be running a better radiator than stock though...
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OP, you still should be running a better radiator than stock though...