160 deg Tstat install and results
#46
I'm starting to wonder now if my C4S X51 got the lower temp thermostat installed. It's almost never above 200 degrees (only when I got stuck in Los Angeles traffic seemingly forever), and it takes forever to get there. Guess I'll have to dig through the maintenance records again.
#47
If you think that changing out the tstat from 180F to 160F lowers the normal operating temp, then by that logic, don't even install one - or say you find a hypothetical tstat that opens at 100F or even 10F. Do you think your engine is going to run 60F or 150F cooler?
#48
I have the 160 thermostat on mine, came with the new engine, part of RND's protocols. I don't know how much of a difference it makes in warmup here, as the outside temp rarely dips below 50F, and only a few days a year. I don't really see a difference in operating oil temp, but it's hard to tell because I never kept data on what the max temp was under specific driving conditions (trip length, revs, outside temperatures, etc.).
I would think though that if the goal was keeping a lid on the maximum operating temp, one would be looking at an add-on oil cooler, larger or additional radiator/fans, higher volume/flow water pump etc. right?
I would think though that if the goal was keeping a lid on the maximum operating temp, one would be looking at an add-on oil cooler, larger or additional radiator/fans, higher volume/flow water pump etc. right?
#49
If we start seeing scored bores in motors where people are running the LTT and have owned their cars for a year or so and follow proper drive off and warm up procedures, then we'll know the LTT doesn't help with that, but until then, it's a hypothesis that makes sense to me and one I'll stick with for my 2 cars.
#50
One person's data point does not make a case. A thermostat does not affect the normal operating temperature of an engine, except in exceptionally cold weather, where it affects the low end of the range. Once a correctly-functioning thermostat is open, it is open. It doesn't matter if it is a 180, a 160 or a 100 degree Tstat. Once the Tstat is fully open, the temperature you see on the gauge is dictated only by the thermal efficiency of the car's entire cooling system. The Tstat is out of the equation.
This isn't my opinion. This is fact.
I will not argue the benefits of a 160 Tstat towards eliminating bore scoring. Engine builders on this forum claim the slowed warming effect of the 160 keeps one or two of the cylinders from heating up too fast and scoring. That may or may not be the case. Keep in mind that one of those engine builders recently stated on a thread on this forum that installing a 160 and going with thicker oil will reduce your chances of bore scoring but increase your chances of crank failure and so he recommends a "pre-emptive" engine rebuild at 85k miles. To me, that sounds ridiculous.
But, whether or not the 160 does reduce your chances of bore scoring in this particular engine, it does not, and never will, reduce your normal operating temperature. Thermostats don't work that way. 180 or 160, once they're open, they do exactly the same thing--nothing. They sit there and flow the exact same amount of coolant at the exact same rate.
This isn't my opinion. This is fact.
I will not argue the benefits of a 160 Tstat towards eliminating bore scoring. Engine builders on this forum claim the slowed warming effect of the 160 keeps one or two of the cylinders from heating up too fast and scoring. That may or may not be the case. Keep in mind that one of those engine builders recently stated on a thread on this forum that installing a 160 and going with thicker oil will reduce your chances of bore scoring but increase your chances of crank failure and so he recommends a "pre-emptive" engine rebuild at 85k miles. To me, that sounds ridiculous.
But, whether or not the 160 does reduce your chances of bore scoring in this particular engine, it does not, and never will, reduce your normal operating temperature. Thermostats don't work that way. 180 or 160, once they're open, they do exactly the same thing--nothing. They sit there and flow the exact same amount of coolant at the exact same rate.
I recently replaced my AC condensers because I saw that they were hammered closed when I put in new radiators. My goal was to improve the restricted air flow to the radiators. After the install my coolant temps dropped to the normal operating temp range of 180 to 183. I bet if I removed my Zunsport protective grills and allowed even more air to enter that those temps would drop further.
So is it possible that with a 180 thermostat that my car's thermostat might not fully open all the time during normal driving conditions?
#51
When I replaced my waterpump a few months ago I routinely replaced the thermostat with the same one that was in it (factory installed). I had no issues with temps before so I figured there was no need to change anything. Only recently when I was in a very odd high temp situation in Las Vegas recently did I actually see oil temps at 250F and my water actually went to 200F indicated.
#52
Have been following this tread and amazed how OCD a Porsche enthusiasts can get and spends time splitting hairs. I'll include myself and will save my own stories. I've been a member for little over 2 years on purchasing my 997.2 C2S and 10 years owned a BMW e46 M3 with Dinan S3 supercharger and suspension upgrades. Before getting married and raising 2 kids, had a hobby of working on late 70's 911's in the 80's. Started with a VW Beetle and graduated to a flat 6. Even tinkered with 914's.
I just drove my C2S cold from my garage as I normally do, 2 miles on a country road to the highway for another 8 miles on the highway. Drove it normally and in the habit to wait until water and oil temperatures are up to normal temps. Not pushing her at all, running it no higher tha 2,500 RPM. Oil pressure gauge moving between 2 to 3 bars, 70 MPH in 7th gear around 2000 rpm's. After ten miles car oil temp was low at 175. Between the 150 to 200 gauge. Water temp came up quickly 5 miles into the ride to a static 175. It's summer here in the NE, why would I worry, or care if the oil thermostat valve opens 20 degrees before stock 180 degrees. Isn't the piont of the tstat whether at the radiator or oil distribution to bring them up to temp quicker and would fully open on reach rated temps. If they don't, it's a part replacement for a malfunctioning tstat? Once fully open, tstats have done their job and have no effect on a fully warmed up engine. Whether it's During DD, or spirited driving.
My morning drive focused on this tread and working to keeping my OCD in check. Thanks
I just drove my C2S cold from my garage as I normally do, 2 miles on a country road to the highway for another 8 miles on the highway. Drove it normally and in the habit to wait until water and oil temperatures are up to normal temps. Not pushing her at all, running it no higher tha 2,500 RPM. Oil pressure gauge moving between 2 to 3 bars, 70 MPH in 7th gear around 2000 rpm's. After ten miles car oil temp was low at 175. Between the 150 to 200 gauge. Water temp came up quickly 5 miles into the ride to a static 175. It's summer here in the NE, why would I worry, or care if the oil thermostat valve opens 20 degrees before stock 180 degrees. Isn't the piont of the tstat whether at the radiator or oil distribution to bring them up to temp quicker and would fully open on reach rated temps. If they don't, it's a part replacement for a malfunctioning tstat? Once fully open, tstats have done their job and have no effect on a fully warmed up engine. Whether it's During DD, or spirited driving.
My morning drive focused on this tread and working to keeping my OCD in check. Thanks
#53
#54
Noticed my oil temp was running high (225-235)on the way home from work last night on my 05 C2. Spirited highway driving 3-5k rpm , 80 degrees outside Motul 5-40 (which Jake R. says does run hotter) stock thermostat, oil level at middle bar, water 175, oil pressure good. Sending unit replaced few months ago. Is this normal or any ideas?. Oh , zunnsport grilles on and rads look fairly clean.
#55
.2 cars have multi proportional controls to send different pressures to different parts of the motor depending upon operating conditions. The pressure never tops out. My question might be, given that there are multiple pressures ... What is the pressure gauge really showing?
#56
Petza914, you're feeding my OCD. Thank you
#57
.2 cars have multi proportional controls to send different pressures to different parts of the motor depenNding upon operating conditions. The pressure never tops out. My question might be, given that there are multiple pressures ... What is the pressure gauge really showing?
#58
.2 cars have multi proportional controls to send different pressures to different parts of the motor depending upon operating conditions. The pressure never tops out. My question might be, given that there are multiple pressures ... What is the pressure gauge really showing?
Peace
Bruce in Philly
#59
But none of that has anything to do with the fundamental operating principal behind the Tstat. Just think about how paranoid we would all be if the sending unit was adjacent to a cylinder! The temperature variations there would drive us to distraction, not to mention the gauge would become useless as it would constantly be moving.
On a side note, at least one person mentioned that when he tested his 180 degree Tstat, it was not opening correctly and that his 160 degree opened at exactly the right time. I assume he mentioned that as a rationale as to why going to the 160 made sense. To me, that only showed that his Tstat was malfunctioning and that a new 180 unit would have worked just fine. All Tstats can malfunction, no matter what their temperature rating. I always check my Tstats in a pot of water before I install them because on more than one occasion, I installed one (in old Fords, not Porsches) and it was bad out of the box. It just happens sometimes.
#60
One person's data point does not make a case. A thermostat does not affect the normal operating temperature of an engine, except in exceptionally cold weather, where it affects the low end of the range. Once a correctly-functioning thermostat is open, it is open. It doesn't matter if it is a 180, a 160 or a 100 degree Tstat. Once the Tstat is fully open, the temperature you see on the gauge is dictated only by the thermal efficiency of the car's entire cooling system. The Tstat is out of the equation.
This isn't my opinion. This is fact.
I will not argue the benefits of a 160 Tstat towards eliminating bore scoring. Engine builders on this forum claim the slowed warming effect of the 160 keeps one or two of the cylinders from heating up too fast and scoring. That may or may not be the case. Keep in mind that one of those engine builders recently stated on a thread on this forum that installing a 160 and going with thicker oil will reduce your chances of bore scoring but increase your chances of crank failure and so he recommends a "pre-emptive" engine rebuild at 85k miles. To me, that sounds ridiculous.
But, whether or not the 160 does reduce your chances of bore scoring in this particular engine, it does not, and never will, reduce your normal operating temperature. Thermostats don't work that way. 180 or 160, once they're open, they do exactly the same thing--nothing. They sit there and flow the exact same amount of coolant at the exact same rate.
This isn't my opinion. This is fact.
I will not argue the benefits of a 160 Tstat towards eliminating bore scoring. Engine builders on this forum claim the slowed warming effect of the 160 keeps one or two of the cylinders from heating up too fast and scoring. That may or may not be the case. Keep in mind that one of those engine builders recently stated on a thread on this forum that installing a 160 and going with thicker oil will reduce your chances of bore scoring but increase your chances of crank failure and so he recommends a "pre-emptive" engine rebuild at 85k miles. To me, that sounds ridiculous.
But, whether or not the 160 does reduce your chances of bore scoring in this particular engine, it does not, and never will, reduce your normal operating temperature. Thermostats don't work that way. 180 or 160, once they're open, they do exactly the same thing--nothing. They sit there and flow the exact same amount of coolant at the exact same rate.