Quote:
Originally Posted by Harley Kidd
Has anyone put one of these 160 thermostats in their car? I used to do this all the time with my older vintage cars, however, I am wondering if this change will cause problems with the ECM or something else that is factory set to work at the temp they wanted the car to operate at.
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Aluminum does not transmit heat out as well as steel does.
Car powertrains of today only purpose to be forced to run hotter is for smog purposes to keep exhaust, 02 sensors and CATs hotter and why EPA requires those parts not be moved.
This can be shown as years ago the CATs were mid stream and today they are closer to the heads where exhaust temps are HOTTER.
Cannot override nature, the hotter the engine bay is the more friction there is, the more molecules in air and fuel separate and hence less of them per volume space.
This makes for a worse charge to cylinders, not as good of a burn, leaner AFR which causes PCM to command fuel injectors on longer to the point they can be too small for the performance output.
Look at the front of a C5 Corvette and then the nose of the C6 as GM found they needed more cooler air so they increased the air volume to help cool the radiator more.
Look at the new ZR1 you see it uses a larger radiator then other C6 models and check out the new Z07 and Z06 options just released you'll see they also now come with a larger radiator. Also look at the new Z07 hood or the C6R and you see a nice big hole in it to help pull engine and bay temps down.
Just because a lower Tsat like a 170 degree is used does not mean the temps stay there as the norm, most cases once engine is warmed up due to smaller radiator volume flow the engine will still run hotter then Tstat setting.
If living in cold country during the winter you always could run a tune with fans set higher and another tune for summer or race conditions set with fan settings closed to Tstat opening used.
Consider the engine oil runs hotter then the water/fluids that heat is then transmitted into that water temp so because even if water is 170ish the oil temp is still hotter.
Consider the hotter engine is then means the hotter total engine bay is.
This effects even the temp of fuel in fuel rails, injectors, air in intake, to effects to all other parts in the engine bay.
Many of us not only use cooler Tstats but also better flowing radiators, engine oil coolers and even less anti freeze ratio since water transmits heat out better.
Many of us also use water/methanol injection to force air temps much lower for a end result of a far better cold charge in cylinders which makes more power and reduces engine ping which would force PCM to reduce timing and kill off torque.
Assuring AFR does not lean out allows even more timing to be added via the tune which increases performance across the board.
In 45 years of driving/racing I have never used a stock Tstat and using all of the above and even in northern cold weather the engine temps never go below mid 170s with no harm long term to engine or performance.
Denser (cooler) air and fuel burn better where hotter temps do not and we all know that in why boost of any kind the more condense the air is the more performance is produced.
Bi-product of having a hotter engine bay cause fuel in fuel rail and injectors to dry out when engine is turned off as heat soak increases and leave deposits and allows engine to heat soak worse effecting off the line performance.